BOTY 2404, Survey of the Plant Kingdom

All information for this course, including Lab Instructions, will be located on this Homepage. You will be kept up on changes in schedule, and on changes in organisms for which you are responsible. There will be a checklist of organisms from lab which should be included in your notebook and a list of organisms that we will not see, even though they are mentioned in the lab instructions.

Change of Schedule! The final will be changed to a scavenger hunt to be held on Thursday, 29 June.

BOTY 2404, Survey of the Plant Kingdom, Summer, 2000

Instructor: Dr. Fred Spiegel, SCEN 711, phone: 575-7393, email: fspiegel@comp.uark.edu, Homepage: http://comp.uark.edu/~fspiegel/

Office hours: TWR - 8-9:15 and by appointment

Text: Raven, Evert, and Eichhorn, Biology of Plants, 6th Ed. This is an excellent book that you can also use as a reference to remind you of the principles of biology that are fundamental to this course. You may also use Moore, Clark, and Vodopich, Botany, 2nd Ed. if you wish. This is the text that is used in BOTY 1613. Many reference books will be available in the lab as well.

Supplies: A 3-ring binder, plenty of Botany Paper, a 3H pencil (or drawing pen, or colored pencils), a good eraser.

lass and Grading Policies: Lab and lecture material will complement each other. Come each day ready to start each scheduled activity. Grades will be based on: 1) two semester exams and a final exam (@ 60%) and 2) your lab notebook and completion of two semester projects (@40%). All exams will be based on questions asked from a set of projected slides which you will be able to study in advance. The final exam will include a scavenger hunt. All exams are comprehensive in nature. See Recommended Study Aid below. Your lab notebook will consist of drawings and answers to questions given in the different lab exercises. Lab assignments for the semester are described below. You are expected attend all classes and labs. Because labs may involve walking field trips to collect specimens, always come prepared to go outside; i.e, wear appropriate clothes and shoes.

The grading scale on the exams is as follows:

I reserve the privilege of lowering the cutoff for exam grades but I will never raise them. That is, a 68% will never be a B or lower, but I might decide that a 51% is a D.

Lab notebooks will be graded based on completeness of your coverage of organisms seen in class, the inclusion and quality of your Flower to Fruit Exercise (see below), and the inclusion of your List of Principles (see below). Completeness of coverage means inclusion of your original drawings of organisms with appropriate labeling. There will be a checklist against which to evaluate your completeness of coverage (see below).

Weather Policy: As long as the University is open, class will meet. If we experience inclement weather in Northwest Arkansas such that you feel that it is unsafe for you to attend, you should not put yourself at risk. I will reschedule any exams scheduled on days when weather creates a travel risk.

Semester Lab Assignments:

1. Compile a list of fundamental biological concepts or principles that have been discovered and/or illustrated using botanical organisms. Example:

Principle

Discoverer

Organism or group of organisms

Organisms made of Cells

Hooke

Cork Oak (Quecus suber)

2. Flower - to - Fruit. Find an angiosperm that is flowering and producing fruit. Illustrate the development of the flower and the fruit from the flower bud stage to the mature fruit stage. Illustrations should be drawings or photographs. (See me if you wish to do the latter.) Do not shortchange this exercise by waiting until the last minute. You should be well under way by mid March. Also, illustrate as many stages of development as you can. You cannot overdo this project. We will take several field trips in February and March to show you plants that will work well as subjects.

3. Lab Notebook. Prior to each lab, the instructions for that lab will be posted on this page. Download them, and read them before lab meets. The notebook should be laid out as follows:

To aid you in keeping track of what we actually cover in lab, there will be a set of checklists posted below to let you know which organisms should be drawn in your notebook and what structures should be labeled. Any entry marked with x will be something you should have included. Any entry marked with o indicates something that many people saw. If a subject is left blank, it means our plans did not work out. Sometimes the checklist will include examples that were not on the lab instructions because something good came up.


Topic Coverage

Tentative Schedule of Topics (Certain organisms may occur in abundance in lab collections before or after we are scheduled to cover them; therefore, we may cover them out of order. I will give you specific instructions in those cases)

Date

Topic

Suggested Reading and Assignment

22 May

Introduction to Botanical Organisms and Lab

Chap. 13, 14 thru p. 296

23 May

Cyanobacteria

Chap. 13, 14 thru p. 296. Bring pond-bottom and water samples to lab

24 May

Introduction to Eukaryotes, Miscellaneous Protist Algae (Euglenoids, Dinoflagellates, and Cryptomonads)

Chap. 16, pp. 348-352, 356-357, 361-366. Bring pond-bottom and water samples to lab.

25 May

Stramenopiles (aka Heterokonts)

Chap. 17 thru p. 385. Bring pond-bottom and water samples to lab

29 May

Memorial Day Holiday, No Classes

30 May

Stramenopiles continued

Chap. 17 thru p. 385. Bring pond-bottom and water samples to lab

31 May

Stramenopiles concluded

Chap. 17 thru p. 385. Bring pond-bottom and water samples to lab

1 June

Mycetozoans (Optional)

Chap. 16, pp. 352-356

5 June

Exam I (thru Stramenopiles) CHANGE

6 June

Fungi, Chytridiomycetes

Chap. 15

7 June

Fungi, Zygomycetes

Chap. 15

8 June

Fungi, Ascomycetes

Chap. 15

12 June

Fungi, Basidiomycetes

Chap. 15

13 June

Red Algae

Chap. 16, pp. 357-362

14 June

Green Algae

Chap. 17, pp. 383-398. Bring pond-bottom and water samples to lab

15 June

The Land Plant Life Cycle, The Fern Example

Chap. 19

19 June

Exam II (thru Red Algae) CHANGE

20 June

Mosses, Liverworts, and Hornworts

Chap. 18

21 June

Lycopods, Horsetails, and Ferns

Chap. 19

22 June

Seed Plants I, habits

Chap. 20-22

26 June

Seed Plants II, male parts

Chap. 20-22

27 June

Seed Plants III, female parts

Chap. 20-22

28 June

Review and Scavenger Hunt

Chap. 20-22

29 June

Final Exam


Recommended Study Aid. You should construct a table of the major groups of organisms we study in the course. It may include your own drawings and written information. You may not include any xeroxed information. I suggest that you construct this as a table, and in the case of all the groups of eukaryotes, you should arrange the columns in the following life cycle order:

For some eukaryotes we will study only a single somatic state, so a life cycle would not be appropriate. You may bring this table to each exam. For the first exam, it may not exceed two sides of 8.5x11 paper. For the second exam, no more than 4 sides. For the final, no more than 6 sides.


Stuff to Know for BOTY 2404, Spring 2000

This list may change as the semester goes along. It is a starting point. Everything in red is stuff you need for the first exam. Everything in red and blue is stuff you need for the second exam. Everything in red, blue, and black is stuff you need to know for the final.

General: Know the terms in bold type in your lab instructions. Life cycles marked with * are illustrated in your text.

Cyanobacteria: Thylakoid, phycobilisome, photosynthetic pigments, gas vacuole, cell wall, unicellular thallus, colonial thallus, filamentous thallus, false-branching thallus, branching thallus, heterocyst, akinete, stromatolite, cyanobacterial mat

Euglenoids: Euglena, Pellicle, Paramylon, Reservoir;

Dinoflagellates: Peridinium, Cingulum, Sulcus

Eukaryotes: Nucleus, mitosis, meiosis, sex, gamete, zygote, endosymbiosis, organelle, flagellum(a), coenocytic vs. uninucleate thalli, ploidy, pyrenoid, isomorphic vs. heteromorphic alternation of generations, sporophyte vs. gametophyte, gametangium, isogamy vs. anisogamy vs. oogamy

Stramenopiles: Whiplash vs. tinsel flagellum, photosynthetic pigments (when present), unicell, motile unicell, colony, motile colony, filament, mitochondrial morphology

Simple Stramenopile Algae: Chrysophyceae, Xanthophyceae, Bacillariophyceae, Diatoms, plastid structure, lorica, cell wall, frustule, centric vs. pennate diatom, valve vs. girdle

Oomycetes: Hypha, zoosporangium, zoospore, antheridial branch, antheridium, fertilization tube, oogonium, egg (oosphere), oospore (zygote), Saprolegniales, Peronosporales

Phaeophyta, Brown Algae: Plurilocular gametangium, plurilocular zoosporangium, unilocular zoosporangium, kelp, holdfast, stipe, blade, kelp oogonium, kelp antheridium, kelp zoosporangium, Fucus oogonium, Fucus antheridium

Myxomycetes (if covered): Fruiting body, Spore, Amoeboflagellate, Plasmodium

Dictyostelid Cellular Slime Molds (if covered): Fruiting body, Spore, Amoeba, Aggregation, Slug

Fungi General: Hypha, Mycelium, Monocentric thallus, Yeast, Dikaryon

Chytridiomycetes: Monocentric chytrids, Zoosporangium, Zoospores, Rhizoids, Allomyces, Male and Female Gametangia, Zoosporangia, Resting sporangia.

Zygomycetes: Mucorales, Sporangium, Sporangiophore, Zygospore, Pilobolus, Rhizopus.

Ascomycetes: Ascus, Ascospore, Fruiting body, Apothecium, Perithecium, Conidium, Conidiophore, Saccharomyces, Lichen

Basidiomycetes: Agarics, Mushroom, Cap, Stipe, Gill, Basidium, Basidiospore, Rust, Telium,Teliospore, Spermagonium, Spermatium, Aecium, Aeciospore.

Red Algae: Florideophyceae, Polysiphonia, Male and Female Gametophytes, Tetrasporophyte, Carposporophyte, Spermatangium, Spermatium, Carpogonium (=Egg), Cystocarp, Carpospore, Carposporangium/carpospore, Tetrasporangium/tetraspore

Green Algae: Chlorophyceae, Ulvophyceae, Charophyceae, Thallus types, Chlamydomonas, Volvox, Chara, Spirogyra, Ulva, Zoosporangia, Zoospores, Gametes, Gametangia

Land Plants in General: Heteromorphic alternation of generations, Archegonium, Antheridium, Embryo, Spore mother cell, Spore, Triradiate ridge

"Bryophytes" in General: Dominant, free living gametophyte, Dependent sporophyte with single sporangium

Liverworts: Thallose vs. leafy liverworts, Marchantia, Reboulia, Pore, Rhizoid, Scale, Gemma, Gemma Cup, Antheridiophore, Sperm structure, Archegoniophore, Foot, Seta, Sporangium (aka Capsule), Spore, Elater, Determinate growth of sporophyte

Mosses: Protonema, Leafy gametophyte, Axis, "Leaf", Rhizoid, Polytrichum, Mnium, Sphagnum, Splash cup, Antheridial head, Archegonial head, Sperm structure, Foot, Seta, Sporangium (aka Capsule), Stoma, Peristome, Operculum, Determinate growth of sporophyte

Hornworts: Single plastid with pyrenoid, Algal symbiont, Rhizoid, Phaeoceros, Antheridial chamber, Simple archegonium, Involucre, Foot, Basal meristem, Sporangium, Columella, Indeterminate growth of sporophyte

Vascular Plants in General: Free living or dependent gametophyte, Gametophytes with reduced or absent gametangia, Dominant, free living sporophyte with xylem and phloem and, usually, stems with leaves (shoot) with nodes and internodes, and roots, and multiple sporangia, Rhizome vs root.

Lycopods: Microphyllous, Homosporous (Lycopodia) or Heterosporous (Ligulate lycopods), Cone (aka Strobilus), Sporangium with spores, Microsporangium with Microspores, Megasporangium with Megaspores, Bisexual gametophyte, Microgametophyte, Megagametophyte, Lycopodium, s.l, Selaginella, Isoetes

Horsetails: Megaphyllous, Small leaves in whorls, Node/Internode arrangement pronounced, Cone, Sporangiophore, Homospory, Elaters, Gametophyte, Sperm structure, Equisetum

Ferns: Megaphyllous, Leaves as fronds, Fiddlehead(aka Crozier), Sorus, Indusium, Annulus, Lip cells, Gametophyte, Position of gametangia, Sperm structure

Seed Plants in General: Megaphyllous, Woody or secondarily herbaceous, Heterosporous, Gametophyte development dependent, Microsporangium/Pollen Sac, Pollen Microgametophyte, Pollen tube, Two sperm, Ovule, Nucellus/Megasporangium, Megaspore -> megagametophyte, Seed

Cycads: Pinnately compound leaves, Trees or "shrubs", Dioecious, Male cones, Microsporophylls, Pollen sacs, Pollen structurem Sperm structure, Female cones, Megasporophylls, Ovules, Archegonia, Seed structure, Zamia, Cycas

Ginkgo: Trees with fan shaped leaves, Dioecious, Male cones, Microsporophylls, Pollen sacs, Pollen structure, Sperm structure, Ovuliferous appendages, Ovules, Archegonia, Seed structure

Conifers: Trees and shrubs, Monoecious or dioecious, Male cones, Pollen sacs, Pollen structure, Sperm structure, Female cones, Ovuliferous scales, Ovules, Archegonia, Seed structure, Pinus

Flowering Plants: Trees, shrubs, and herbs, "Dicot" vs monocot, Monoecious or dioecious, Flower, Sepal, Petal, Stamen, Anther, Pistil, Stigma, Style, Ovary, Carpel, Fruit, Pollen structure, Sperm structure, Ovule structure, Embryo sac/Megagametophyte structure, Double Fertilization, Endosperm, Lilium

Life Cycles to Know (examples with * are found in your text): Vaucheria, Saprolegnia*, Ectocarpus, Fucus*, Kelp*,Polysiphonia*, Myxomycetes*, Allomyces*, Rhizopus*, Filamentous Ascomycetes*, Filamentous Basidiomycetes*, Chlamydomonas (be able to apply this to any freshwater greens)*, Fern*, Moss*, Marchantia*, Hornwort, Lycopodium*, Selaginella*, Equisetum*, Pinus*, Flowering plant*.


Laboratory Instructions and Checklists, Summer Version

Keep track of these to add the exercises for the following week's labs. As we get to it, each lab will be followed by a checklist for that exercise. Keep checking the checklists in case a late breaking observation has been made. The lab instructions and checklists will be updated throughout the summer so don't print them off too far in advance.


Rules for the Lab in Plant Kingdom


Survey of the Plant Kingdom Laboratory, Introduction

Lab Notebook, Arrangement and Preparation of Drawings

Arrangement of Drawings. Your lab notebook will consist primarily of drawings of the organisms we encounter throughout the semester. Drawings must be in pencil (3H or colored pencil) or ink on Botany Paper, a 3 hole-punched, heavy, high quality drawing paper. The drawings of organisms must be arranged by exercise with the directions that cover each exercise. You must limit your drawings to one organism (genus) per page unless we explicitly tell you otherwise. You may add to a page when you encounter the organism repeatedly. Each page must identify the organism to genus (when possible) and have labels for all the important structures. Pay particular attention to terms that are in bold print in the directions to each exercise. Each page should include as many habit and detail drawings as is appropriate (see below).

The Habit Drawing. A habit (not habitat) drawing is a drawing of the whole organism, or a very large portion of the organism. The purpose of such a drawing is to give an idea of what the whole organism looks like and to arrange the drawing in such a manner as to show the important characteristics of the organism. In the habit drawing, you must learn to exercise some editorial control over yourself by learning to recognize that it is not necessary to draw lots of examples of repeated parts. The goal of the habit drawing is to make an accurate representation of the important aspects of the whole organism. Remember, pretty is not as important as accurate. Remember, a habit drawing may be of either a macroscopic or a microscopic organism.

The Detail Drawing. Detail drawings, as should seem obvious, are drawings of parts of an organism that are important and need to be highlighted. Remember, a detail drawing may be of a macroscopic or microscopic structure.

Introduction to Drawing. Several organisms will be available for you to draw. First you will make habit drawings of some macroscopic organisms. Make sure you draw all the obvious structures accurately. Draw lines to the structures that you think should be labelled. (You do not have to worry about actual labels at this point.) Next, make some detail drawings of macroscopic parts of the first organism you drew. Again, draw lines to the structures you think should be labelled. Next, make some drawings of material on prepared microscope slides. Make one drawing using the 10x objective (low power) and one of a detail using the 40x objective (high dry power). Add the indicator lines as above. Finally make a wet mount of one of the specimens that will be provided and make a low power and a high dry power drawing of something interesting. Remember to add the indicator lines.


I. Cyanobacteria and Miscellaneous Protist Algae

In the water and soil samples we have in class, there will be numerous algae from several groups. We will study them as we encounter them. You must organize them into the appropriate phylogenetic groups.

Bacteria - Cyanobacteria. These are the only prokaryotic organisms we will study. Cyanobacteria are the Gram negative bacteria which have evolved oxygen-generating photosynthesis. Many of them are also capable of fixing atmospheric nitrogen. They are found in all types of habitats in which there is sufficient light for photosynthesis. We will find them in soil and water samples and focus primarily on the diversity morphology found in the group.

Unicellular Forms: Look for single cells or small groups of cells that are greenish but show no internal substructure. Examples: Gloeocapsa sp., Chroococcus sp.

Colonial Forms: Look for clusters of cells with either a distinct shape or in an amorphous mass. They will typically share a common sheath. Examples: Microcystis sp., Gomphosphaeria sp., Merismopedia sp.

Filamentous Forms:

Simple Unbranched Filaments: Examples: Oscillatoria sp., Lyngbya sp.

Unbranched Filaments with Heterocysts and/or Akinetes: Examples: Anabaena sp., Cylindrospermum sp.

Colonies of Unbranched Filaments: Examples: Nostoc sp. (with heterocysts), Microcoleus sp. (without heterocysts)

Tapered Filaments: Examples: Calothrix sp., Gloeotrichia sp.

Pseudobranched Filaments: Examples: Tolypothriix sp., Scytonema sp.

Branched Filaments: Example: Stigonema sp. (slide)

 

Eukaryotes - Miscellaneous Protist Algae

Pyrrhophyta - Dinoflagellates. These are usually motile, unicellular algae with two flagella. One flagellum is located in a groove, the cingulum, which wraps around the middle of the cell, the other extends from a longitudinal groove, the sulcus, which is arranged at right angles and posterior to the cingulum. Examples: Ceratium sp., Peridinium sp.

Euglenophyta - Euglenoids. These are unicellular flagellated algae which may range from very flexible to rigid. The cells are bright green and have an anterior, orange eye spot. The flagella arise from an indentation called the reservoir. Examples: Euglena sp., Phacus sp.


Cyanobacteria: Checklist of Bluegreens for Lab Notebook

Unicellular Cyanobacteria

_____Synechocystis sp., Label _____cell

__x___Gloeocapsa sp. and/or Chroococcus sp., Label __x__cell, __x__sheath

Colonial Cyanobacteria

_____Merismopedia sp., Label ____cell, ____dividing cell, ____sheath

__x___Coelosphaerium sp. and/or Gomphosphaeria sp., Label __x__cell, __x__gas vacuoles, __x__sheath

Simple, Unbranched Filamentous Cyanobacteria without Heterocysts

___x__Oscillatoria sp., Label _x___cell, __x__dividing cell, __x__separation cell

Unbranched Filaments with Heterocysts and/or Akinetes

___x__Anabaena sp., Label __x__cell, __x__dividing cell, __x__heterocyst, _____ akinete (if seen)

_____Cylindrospermum sp., Label ____cell, ____terminal heterocyst, ____subterminal akinete

Colonies of Unbranched Filaments

__x___Microcoleus sp., Label __x__filaments, __x__common sheath, ___x__Habit

__x____Nostoc sp., Label __x__filaments with heterocysts, _x___common sheath

_____Aphanizomenon sp., Label ____filaments, ____gas vacuoles

Tapered Filaments

__x__Calothrix sp. or Rivularia sp., Label __x___cell, __x__terminal heterocyst, _x___sheath

Pseudobranched Filaments

__x___Scytonema sp. and/or Tolypothrix sp., Label __x__cell, ___x_heterocyst, __x__sheath, __x__false branch

Branched Filaments

_____Stigonema sp. (prepared slide), Label ____cell, ____heterocyst, ____sheath, ____branch

Cyanobacteria you might have seen and drawn

Lyngbya sp., Spirulina sp.


Miscellaneous Protist Algae: Dinoflagellates and Euglenoids: Checklist for Notebook

Dinoflagellates

Peridinium sp. or Ceratium sp. ___x__Habit, Label __x__cingulum, __x__sulcus, __x__nucleus (if seen), __x__plastids, __o___girdle flagellum (if seen), _o___trailing flagellum (if seen), __x__plates

Euglenoids

Euglena sp. __x___Habit, Label __x___flagellum (if seen), ___x__canal and reservoir, ___x__eyespot, __o___contactile vacuole, __x___plastids, __x___paramylon, ___o__nucleus (if seen), ___o__pellicle

Phacus sp. _x___Habit, Label __x__flagellum, __x__canal and reservoir, __x__eyespot, __o__contractile vacuole, __x__plastids, __x__paramylon, __x__nucleus, __x__pellicle

Astasia sp. (a colorless euglenoid) ___x__Habit, Label __x__flagellum, __x__canal and reservoir, __o__nucleus, __x__paramylon, __o__pellicle

Trachelomonas sp. ___o__Habit, Label __o__lorica, __o__flagellum, __o__cell

Cryptomonads

Cryptomonas sp.___o___Habit, Label ___o_flagella (2), ___o_gullet, __o__ejectosomes, ___o_nucleus, __o__plastid


II. Stramenopile Protists

Chrysophytes, Xanthophytes, and Diatoms: Small Stramenopile Algae.

Find, examine, and draw, if you can, one or more of the following chrysophytes in our water samples: Mallomonas sp., Dinobryon sp., and/or Synura sp.

Examine the coenocytic filaments of the xanthophyte, Vaucheria sp. Notice that the thallus, the body, is a branching filamentous system that consists of a single cell. Sketch the habit of this alga and a detail of one of its filaments. If found, draw a zoosporangium, a zoospore, a zoospore cyst, an antheridium, and an oogonium.

Find a diatom, and draw it in both valve and girdle views. Show the frustules, vacuole, nucleus, and chloroplasts. The pennate diatom, Navicula, would be a good example to look for. Other diatoms we find will be identified on the blackboard.

 

Oomycota, the Oomycetes or Water Molds.

The oomycetes are classically treated as fungi because of their lysotrophic mode of nutrition and their mycelial growth form. Examine mycelia of oomycetes growing on sesame seeds in your water samples. Mount a seed in water in a small petri dish and place the dish on a slide. Look for and draw zoosporangia and zoospore release, if found. Also look for and draw oogonia with eggs and/or oospores and antheridia at the tips of antheridial branches. You should move some of your material to a slide so you can draw the material in detail. Common genera you are likely to find are: Saprolegnia, Achlya, Dictyuchus, and Pythium.

 

Phaeophyta, the Brown Algae.

Browns are primarily marine algae that range from small filamentous forms to very large (~ 50m) kelps. Examine herbarium specimens of several brown algae and make habit sketches.

Examine and draw the life cycle stages of the filamentous brown, Ectocarpus sp. from live samples and prepared slides. The gametophyte has only plurilocular gametangia which produce the flagellated gametes. The sporophyte has plurilocular zoosporangia which produce diploid, asexual zoospores and unilocular sporangia which are the sites of meiosis. The unilocular sporangia release haploid zoospores that give rise to gametophytes.

Examine and draw the sporophyte of a kelp. Label the holdfast, stipe, and blade. Examine and draw zoosprorangia (the equivalent of unilocular sporangia) on the demonstration slide.

Examine and draw a specimen of Fucus sp. The bulbous receptacles on the ends of the blades are reproductive structures. Each receptacle contains dozens of conceptacles which contain the gametangia. Section a receptacle such that you section throught one or more conceptacle and look for and draw the gametangia, the oogonia and antheridia. To what structures on Ectocarpus do the gametangia of Fucus correspond?


Fungus Analogs Among the Stramenopiles, The Oomycetes: Checklist for Notebook

Saprolegniales

Saprolegnia sp. (We have also seen some Achlya sp.)

__x___Habit of mycelium live specimen on sesame seed, Label __x__hypha, __x__mycelium, __x__Detail of hypha and reproductive structures, Label __x__vacuole, __x__cytoplasm, __x__zoosporangium, ____zoospore release (if seen), ____primary zoospore (if seen in Saprolegnia), __x___primary zoospore cyst (if seen), ____primary zoospore cyst ball (if seen in Achlya), _____release of typical (aka secondary) zoospore from primary zoospore cyst (if seen in Achlya), ___x_antheridial branch, __x__antheridium, __o__fertilization tube, __x__oogonial initial, __o__oogonium in which eggs are cleaving, __x__mature oogonium with eggs and/or young oospores, __x__mature oogonium with mature oospores, Label __x__oospore wall, __x__laminarin


Simple Stramenopile Algae, Chrysophytes, Xanthophytes, and Diatoms: Checklist for Notebook

Chrysophytes

______ Ochromonas sp. Label _____plastids, _____flagella, _____nucleus (if seen), _____laminarin

___o__ Mallomonas sp. Label __o__plastids, __o__flagellum, __o__nucleus (if seen), __o___laminarin, __o__silica scales

___o__ Dinobryon sp. Label __o__colony, ___o_cell, __o__plastids, __o__eyespot, __o__flagella, __o__nucleus (if seen), __o__laminarin, __o__lorica

_____ Synura sp. Label ____colony, ____cell, ____plastids, ____flagellum, ____nucleus (if seen), ____silica scales

Xanthophytes

_____ Vaucheria sp. Label ____filaments with branches and tips,_____rhizoid, ____plastids, ____central vacuole, ____zoosporangium (if seen), ____antheridium, ____oogonium with egg or zygote

Diatoms

Centric Diatoms

____ Stephanodiscus sp. Label ____ cell in valve view, ____cell in girdle view, ____plastids, ___nucleus, ____oil drops, ____valve, ____girdle bands, ____chitin fibers

Other centric diatoms you might see and draw

Melosira sp.

Pennate Diatoms

__x___ Navicula sp. Label __x__cell in valve view, __x__cell in girdle view, __x__plastids, __x__nucleus, __x__oil drops, __x__valve, __x__raphe, __o__girdle bands

Other pennate diatoms you might see and draw

Asterionella, Fragillaria, Tabellaria, Gomphonema, Cymbella


Plant Analogs among the Stramenopiles, the Brown Algae: Checklist for Notebook

Ectocarpus sp.

__x__ Habit, herbarium specimen, __x___ Habit, live specimen. Label __x__plastids, ___x_pyrenoid, __x__nucleus, __x__plurilocular structure, prepared slide Label _x___unilocular structure, ___x_diagram life cycle

Kelps, Laminaria sp.

__x___Habit, live or herbarium specimen of sporophyte, Label __x__holdfast, ___x_stipe, ___x_blade. Prepared slide of blade, XS, Label ____zoosporangium (a unilocular structure)

Fucus sp.

__x__Habit, live or herbarium specimen, Label ___x_holdfast, __x__stipe, __x__blade, __x__float, __x__receptacle, __x__conceptacle, Prepared slide or freehand section of receptacle with conceptacles, Label __x__conceptacle, __x__ostiole, __x__sterile filaments, __x__oogonium, __x__eggs, __x__antheridium, ___x_sperm


III. Fungi

Chytridiomycetes.

These are the only true fungi with flagellated cells. Flagellated cells have a single posterior flagellum and may be asexual propagules called zoospores, or they may be gametes. Chytridiomycetes may be mycelial or they may be unicellular forms called monocentric chytrids. Monocentric chytrids grow on small substrates such as pollen grains or single algal cells. Mycelial forms grow on larger substrates. Pine pollen that has be sprinkled onto your water samples should be infested with monocentric chytrids. Put some on a slide as demonstrated and look for the spherical zoosporangia of chytrids. Draw some chytrids.

The mycelial chytridiomycete you will be observing is Allomyces arbuscula. This species has growing states in both the haploid and diploid conditions, and, therefore, has an alternation of generations. The haploid gametophyte produces male and female gametangia that produce the gametes. The gametes fuse to produce zygotes which encyst and develop into diploid sporophytes. The sporophytes produce zoosporangia with asexual zoospores and resting spores that will eventually undergo meiosis and release haploid zoospores that encyst and grow into sporophytes. Examine and draw both gametophytes and sporophytes. Watch gamete release and fertilization.

 

Zygomycetes.

The zygomycetes are a group of true fungi which have hypae that are nonseptate. They are usually identified by their asexual reproductive structures, the sporangia and sporangiophores. As an example of the most common order of zygomycetes, the Mucorales, examine and draw the sporangium and sporangiophore of the dung fungus, Pilobolus sp. Be sure to indicate the sporangium and spores, subsporangial swelling, sporangiophore, and the trophocyst. How is this fungus adapted to its habitat. Sexual reproduction in zygomycetes is by means of zygospores. These develop when two compatible hyphae recognize each other and produce gametangia that fuse. Examine and draw the stages of zygosporogenesis from prepared slides of Rhizopus stolonifer.

 

Ascomycetes and Basidiomycetes. These are the most species rich groups of fungi, with the ascomycetes alone estimated to have close to one million species. They have septate hyphae and, usually, a prolonged period of dikaryotic growth between plasmogamy and karyogamy.

Ascomycetes.

As mentioned above, the ascomycetes are the largest group of fungi. They may be mycelial or yeasts. The definitive structure of the group is the ascus - the cell in which karyogamy and meiosis occur and inside of which the sexual spores, the ascospores develop. In many ascomycetes, the asci develop inside a mass of sterile material called the fruiting body or ascocarp. Examine one or more ascocarps from our dung samples. Make a habit drawing, then squash it to reveal the asci. Draw as many stages of ascus development as you can. The fungus you draw will be identified to genus when it is given to you.

Asexual reproduction in ascomycetes is by externally produced spores called conidia (conidium, sing.). There are many types of conidia. Examine and draw the condial fungi set up under the demonstration microscope. The taxa of conidial ascomycetes will be identified for you.

Basidiomycetes.

This group of fungi contains the classical mushrooms as well as important plant pathogens such as the rusts. The definitive structure of the basidiomycetes is the basidium - the cell in which karyogamy and meiosis occur and from which the sexual spores, the basidiospores, bud out. Examine a mushroom and make a habit drawing. Make sure you locate the stipe, cap, and gills. Section the mushroom longitudinally and draw how the gills are attached to the cap and stipe. Make a thin tangential section of the cap and mount it on a slide dry. Look on the gills for basidia producing basidiospores using the microscope. Draw. Crush a small piece of gill in water under a cover slip and draw basidia and basidiospores in detail.


Fungi I: Chytridiomycetes: Checklist for Notebook

Monocentric chytrids

__x___Habit of chytrids on pine pollen at 40x, Label __x__zoosporangium, __o__rhizoids (if seen), __o__immature zoosporangia, __x__mature zoosporangia with cleaved zoospores, __x__zoospore release, __o__zoospore with lipid droplet and flagellum (if flagellum seen)

Allomyces arbuscula

__x___Habit of mycelium on sesame seed

__x___Habit and details of gametophyte with gametangia at 10x and 40x, Label __x__hypha, __x__terminal female gametangium, __o__female gamete release, ___x_subterminal male gametangium, _o___male gamete release,__o__male or female gamete structure including flagellum __o__gamete clustering, ___o_gamete fusion, _o___zygote

__x___Habit and details of sporophyte with sporangia at 10x and 40x, Label __x__hypha, __x_resting sporangium, __x__zoosporangium, ____zoospore release, ____zoospore structure


Fungi II: Zygomycetes, Mucorales: Checklist for Notebook

Rhizopus stolonifer, preserved or prepared slides

__x___Sporangia and sporangiophores from kit at 10x and 40x, Label __x__stolon, __x__rhizoids, ___x_sporangiophore, _x___columella, __x__sporangium, __x__spores

___x__Zygospores and zygosporogenesis from prepared slides at 40x, Label __o__progametangia (if seen), ___x_gametangia, __x__suspensors, __x__young zygospore, ___x_mature zygospore

Pilobolus sp., living material from dung (morning lab)

__x__Habit of sporangia and sporangiophores on dung, Label __x__sporangium, __x__subsporangial swelling, _x___sporangiophore, ___o_dispersed (shot) sporangia


Fungi III: Ascomycetes: Checklist for Notebook

Filamentous ascomycetes, asexual reproduction

___x__Ascomycete anamorph of Fusarium sp., habit of conidia and conidiophores (demo) objective, Label __x__conidiophore,__x__ conidiogenous cell, __x__conidium

Filamentous ascomycetes, sexual reproduction

An ascomycete with an apothecium

__x__Apothecium of Ascobolus immersus, habit, Label __x__sterile wall of apothecium, __x__hymenium, __x__asci

__x__Detail with 10x and 40x objectives, Label __x__sterile tissue of apothecium wall, __o__region of ascogenous hyphae, __x__hymenium with __x__paraphyses and __x__asci, including __o__zygote ascus (if seen), __o__developing ascus, and __x__mature ascus with __x__ascospores

An ascomycete with a perithecium

__x___Podospora sp or Sordaria sp..habit, Label __x__neck and ostiole of perithecium, __x__venter of perithecium, __o__shed ascospores, __x__silhouette (see, I looked it up!) of asci including __o__elongating ascus

___x__Detail of crushed perithecium, Label __x__ascus including __x__developing ascus and __x__mature ascus with __x__ascospores and __x__ascospore appendages

A lichen, Parmelia sp.

___x__Habit, identify whether it is crustose, foliose, or fruticose, Label _x___somatic thallus, ___x_apothecium

___x___Section of thallus including apothecium, Label __x__outer fungal layer, __x__algal and fungal layer, __x__inner fungal layer (if present), __x__apothecium with _x___asci and __x__ascospores

A yeast

_____Saccharomyces cerevisiae habit, Label ____somatic cell, ____bud, ____ascus (if present)


Fungi IV: Basidiomycetes: Checklist for Notebook

Mushroom forming basidiomycetes, Agarics

__x___Habit of mushroom, Russula sp., Label __x__stipe, ____partial veil/annulus (if present), __x__cap, __x__gills

__x___Longitudinal section of mushroom, Label all of above and __x__the way the gills are associated with the stipe

___x__Tangential section of cap including gills (try to observe with 40x objective for details), Label __x__gill, __x__hymenium, ___x_ apex of basidium with __x__four basidiospores on the tips of __x__sterigmata, __x__stages of basidiospore development

__x___Squashed preparation of gill on wet mount observed with 40x objective, Label __x__basidium with sterigmata, __x__free basidiospores

Rusts, the Uredinales

___x__Habit of telial gall of Gymnosporangium juniperi-virginianae on red cedar, Label __x__gall, __x__telial horns

Details of telial horn showing __x__ teliospore (2 young basidia) with __x__ stalk and __x__zygote nucleus in each cell, __x__germtube-like maturing basidium, __o__mature basidium with __o__4 cells with __o__sterigmata, __x__basidiospore


IV. Rhodophyta, the Red Algae.

The reds are primarily marine algae that lack any flagellated stage in the life cycle. Most red algae have a relatively complicated life cycle with two distinct diploid stages, the dependent carposporophyte and the free-living tetrasporophyte, and a haploid stage, the gametophyte. Examine and draw some of the herbarium specimens of red seaweeds. Examine the live specimens and prepared slides of Polysiphonia sp. to see one example of the growth habit and the reproductive stages of the red algae. Draw a filmament from the tip to a region with mature cells. Diagram development and show the pattern of pit connections between cells. On the male gametophytes, draw the spermatangial branches and spermatangia. On the living female gametophyte, draw the young cystocarp with the long trichogyne extending from it. On the mature female gametophyte on the prepared slide, draw the mature cystocarp with the dependent carposporophytes and carposporangia. On the tetrasporophyte, draw the tetrasporangia and tetraspores. From one of the samples, draw a pit connection between the cells. How would you describe the life cycle of this alga?


Red Algae: Checklist for Notebook

Florideophyte red algae

_x__Habits of red algae on herbarium sheet to include Polysiphonia sp. and other growth forms

__x___ Habit of living Polysiphonia sp., ____x_

Polysiphonia sp.

__x__Detail of somatic filament of living and/or prepared specimens, Label __x__apical cell, __x__development of axial and pericentral cells, __x__primary and/or secondary pit connection, __x__plastids

___x__Female gametophyte, living, Label __x__young cystocarp, __x__trichogyne

___x__Female gametophyte, prepared slide, Label __x__mature cystocarp, __x__pericarp, __x__carposporophyte, ___x_carposporangium, __x__carpospore

__x___Male gametophyte, prepared slide, Label _x___spermatangial branch, __x__spermatangium

___x__Tetrasporophyte, prepared slide, Label __o__premeiotic tetrasporangium (if seen), __o__developing postmeiotic tetrasporangium, __x__mature tetrasporangium, __x__tetraspore


V. Chlorophyta, the Green Algae

The green algae are found in both freshwater and marine habitats. One group that is primarily freshwater is the sister group to the land plants. We will concentrate on the various growth forms of the green algae in this lab. If we see evidence of sexual reproduction, that will be pointed out.

Flagellated Unicells. These are unicellular algae that have each cell motile by means of two or more flagella. The most common such alga is Chlamydomonas spp. If you see this, draw it.

Nonflagellated Unicells. These unicellular forms are sedentary or move by gliding. There are numerous such species. The most easy to recognize are the unicellular desmids which consist of cells with two mirror image halves. Find and draw a desmid. The taxon you find will be identified for you.

Flagellated Colonies. These colonies consist of many similar looking flagellated cells, each of which looks similar to Chlamydomonas. In some colonial forms, there may be a division of labor such that most cells are vegetative and a few are reproductive. Volvox spp. have such an organization. Draw Volvox sp. and show the different stages of daughter colony development. If you find sexual reproduction, draw that as well.

Nonflagellated Colonies. These colonies consist entirely of nonflagellated cells, all of which are similar. Some examples you are likely to see include: Hydrodictyon sp., Scenedesmus spp., and Pediastrum spp. Draw one example of a nonflagellated colonial green alga.

Unbranched Filaments. These algae have filaments that have a single file of cells. Some cells may be specialized for reproduction or all may be equally capable of reproduction. Common genera with this growth habit include: Spirogyra spp. and Oedogonium spp. Find and draw one of these algae. Include reproductive structures if you encounter them.

Branched Filaments. These algae have occasional true branches. Some cells may be specialized on them. Common genera include: Bulbochaete sp., Draparnaldia sp., and Stigeoclonium sp. Draw one species with branched filaments. Include reproductive structures if you find them.

Parenchymatous Growth. A genus closely related to land plants that grows as an epiphyte on other algae and submerged plants is Coleochaete sp. If you find some of this alga, draw it.

Blade-like Growth. The marine alga Ulva lactuca has a flattened thallus, two cells thick, and grows in large sheets. Examine and draw a habit of U. lactuca from a herbarium specimen.

Chara sp. This plant like alga has distinct nodes and internodes with whorls of branches at the nodes. Make a habit sketch of this alga or its near relative, Nitella sp.from the demonstration dissecting microscope. Draw the antheridia and oogonia as well. Like Coleochaete, Chara is closely related to the land plants.


Green Algae: Checklist for Notebook

Flagellated Unicells, Chlamydomonas reinhardtii

__x___Habit of somatic cell, Label __x__flagella, __x__chloroplast, __x__pyrenoid, __o__nucleus, __o__eyespot

__o___Mating, Label ____cluster of isogametes, __o__pairing isogametes, ____tetraflagellate zygote, ____mature thick walled zygote

Nonflagellate Unicells, Desmids, e.g. Closterium sp., Cosmarium sp., Staurastrum sp., Micrasterias sp., Euastrum sp.

__x___Habit of somatic cell, Label, __x__semicells, __x__nucleus, __x__chloroplasts, ___x_pyrenoids

_____Mating in Cosmarium sp., Label, ____walls of conjugated gametes, ____zygote

Flagellated Colonies, Volvox sp. (and/or Gonium sp., Pandorina sp.,Eudorina sp.)

___x__Habit of colony, Label __x__common sheath of colony, __x__flagellated somatic cells, __x__reproductive cells (gonidia) or daughter colonies, ____inverting daughter colonies

__o__Details of somatic cell, __o__flagella, __o__eyespot, __o__chloroplast, __o__cytoplasmic strands to adjacent cells

Nonflagellated Colonies, Scenedesmus sp., Pediastrum sp., or other

___x___Habit of colony, Label ___x_ somatic cell with __x__chloroplast, __x__pyrenoid

Unbranched Filaments, Spirogyra sp. and Oedogonium sp., also Ulothrix sp., or other

__x___Habit of filament, Label __o__nucleus, __x__chloroplast, __x__pyrenoids; in Oedogonium sp. __x__annular scars, __x__holdfast

__o___Conjugation in Spirogyra sp. or Zygnema sp., Label __o__cojugation tubes, __o__gametes, __o__zygotes

___x__Sexual reproduction in Oedogonium sp., Label __x__oogonium with egg and/or oogonium with zygote, ____miniature male filament with ____antheridia, ____androsporangia (the small zoosporangia from which the miniature male zoospores were released)

Branched Filaments, Bulbochaete sp, Cladophora sp., Stigeoclonium sp., Draparnaldia sp., or other.

___x__Habit of thallus, Label __x__somatic cell with ___x_chloroplast, __o__nucleus, __x__in Bulbochaete, hair cell with bulbous base

__o___Sexual reproduction in Bulbochaete sp. Label __o__oogonium with egg, __o__oogonium with zygote, __o__miniature male filament with __o__antheridia

Bladelike Thallus, Ulva lactuca

__x___Habit of thallus from herbarium sheet

Chara sp. or Nitella sp.

__x___ Habit of thallus, Label __x__internodes, __x__whorls of branches ("leaves"), ___x_antheridium, __x__oogonium

__x___Details, Label __x__plastids in cell, ___x_gametangia showing __x__jacket of antheridium, __x__jacket of oogonium, __x__egg (or zygote)


VI. The Embryophytes, Land Plants (Kingdom Plantae in your book): Life Cycle

All land plants have a heteromorphic alternation of generations. That is, the sporophyte and gametophyte are distinctly different from each other. In all land plants the sporophyte begins its development inside maternal gametophyte tissue (or a modification of that tissue in the case of flowering plants). This stage is the embryo. All sporophytes mature to produce structures containing cells that are capable of undergoing meiosis. These structures are called sporangia, and the products of meiosis are spores (in land plants, the term "spore" refers only to the products of meiosis). Spores germinate, and germlings develop into gametophytes. We will use the ferns for examples of the land plant life cycle because both their gametophytes and sporophytes are free-living and macroscopic at maturity and because the gametangia and sporangia are easy to observe.

VIa. Ferns - Division Pterophyta.

Ferns are the most species-rich group of land plants after the flowering plants and mosses. They are an ideal group of plants with which to study the land plant life cycle. They have a free-living gametophyte that is somewhat alga-like and a free-living sporophyte that has the major organs and tissues of a vascular plant. It is of the sporophyte that we are typically aware when we see a fern. Make the following observations, draw what you see, and arrange your drawings in life cycle order.

1. Mature vegetative sporophyte. Make a habit drawing of a sporophyte of one of the ferns on display. Locate, draw, and indicate a leaf (aka, frond), the stem, and a root. These organs are found on the sporophytes of almost all vascular plants. Examine a leaf surface and find some stomata; draw. The stoma is a characteristic of the sporophytes of all land plants except for liverworts. Focus through the leaf and observe a vein. You should be able to see elements of the xylem, the water conducting portion of the vascular tissue; draw. Vascular tissue is found in the sporophytes of all vascular plants.

2. Reproductive sporophyte. Find a leaf with patches of green to brown sori on it; such a leaf is a sporophyll. A sorus is a pile of sporangia. Draw a sorus under the dissecting microscope. Pick a sorus with numerous brown sporangia and watch to see if you can observe spore release. Mount sporangia of all ages on a slide and draw the stages of spore development. Be sure to show: a) young sporangia with diploid sporogenous tissue, a tapetum, and a developing sporangial wall; b) sporangia with tetrads of new spores following meiosis; and c) sporangia with mature spores and a mature sporangial wall with annulus and lip cells.

3. Spore germination. Sprinkle some spores onto an agar plate or onto a moistened peat pellet. Next day, observe and draw spore germination. What differentiation do you see in the very young gametophyte?

4. Mature gametophyte. Make a habit sketch of a gametophyte showing the photosynthetic thallus and the rhizoids. Roughly, how many chloroplasts are in each photosynthetic cell? Indicate which is the apical end (the growing point) of the gametophyte.

5. Gametangia. Invert a gametophyte on a slide and mount it in a drop of water under a coverslip. Examine the underside of the gametophyte for antheridia and archegonia (the special name for the oogonia of land plants). Indicate the relative positions of gametangia on the gametophyte. Do all gametophytes have gametangia? Draw an anteridium with sperm in detail. Draw sperm release if you find it. Draw and archegonium with an egg (or zygote) in detail.

6. Developing sporophyte. The zygote begins to divide mitotically while still in the archegonium and the archegonial wall and surrounding gametophyte tissue enlarge with it for a while. Try to find and draw an embryo embedded in a gametophyte. The embryo quickly develops a first stem tip, leaf, and root which expand and break free of the gametophyte tissue. However, a foot of sporophyte tissue remains embedded in the gametophyte as the other organs expand at "germination". The foot draws nutrients from the gametophyte until the young sporophyte begins to yield its own net gain of photosynthate. Once the young sporophyte photosynthesizing on its own, the gametophyte shrivels and dies. Draw a young sporophyte emerging from a gametophyte. Show the primary shoot axis, the embryonic leaf, the primary root, and the foot.


Embryophytes (Land Plants) I: Life Cycle, the fern example: Checklist for Notebook

Adiantum sp., the maidenhair fern

Somatic Diploid, the sporophyte

__x___Habit of sporophyte, Label __x__stem (or rhizome), __x__adventitious roots, __x__leaf (or frond), __x__fiddlehead (unrolling leaf)

Site of meiosis and products of meiosis, the sporangia and spores

__x___Habit of sporophyll, Label __x__sorus and false indusium (flap of tissue at edge of leaf)

___x__Detail of sori at 10x and 40x, Label __x__premeiotic-meiotic sporangium with ___x_stalk, ___x_annulus, __x__lip cells, __x__tapetum, __x__spore mother cells (sporocytes) or young tetrads; ___x_maturing sporangium with __x__ stalk, __x__annulus, __x__lip cells, __x__tapetum, __x__spore separating from tetrads, _x___triradiate ridge on spore; __x__mature sporangium with __x__stalk, __x__annulus, __x__lip cells, __x__mature spores, _x___spore with triradiate ridge

Somatic Haploid, the gametophyte

__x___Germinating spore showing __x__spore wall, __x__photosynthetic filament, __x__rhizoid(s)

__x___Habit of gametophyte, Label __x__photosynthetic tissue, ___x_apical notch, __x__rhizoids, __x__detail of somatic cells of photosynthetic tissue showing __x__chloroplasts

Sites of gamete development and fertilization, the gametangia

__x___Antheridium at 10x and 40x, Label, __x__antheridial wall, __x__operculum, __o__spermatogenous tissue, __x__maturing sperm, _____released sperm

__x___Archegonium at 10x and 40x, Label, __x__neck, __x__neck canal cells in young archegonium, __x__neck canal in mature archegonium, __x__venter, __x__egg, __o__embryo in swollen archegonium

Young sporophyte arising from gametophyte

__x___Habit of young sporophyte emerging from under gametophyte, Label _x___juvenile leaf of young sporophyte,__x__foot, __x__parent gametophyte (Mom), __o__primary root


VIb. Bryophytes.

The bryophytes are those land plants which have a free living, dominant gametophyte and a sporophyte that is dependent (always attached to) the parent gametophyte at the location of an archegonium. The bryophtes are generally treated as three separate divisions: the mosses, Bryophyta; the liverworts, Hepatophyta; and the hornworts, Anthocerophyta. The relationships among these organisms and between them and the other land plants is subject to some debate, but that is beyond the scope of this course. The bryophytes share several similarities that allow us to treat them as a unit to illustrate certain trends of how to be a land plant.

All have a dominant gametophyte and relatively complex gametangia. All have sporophytes consisting of a foot, a stalk (the seta), and a sporangium (the capsule). We will use mosses as our major example of bryophytes and bring in examples of the other divisions to the extent material is available.

Mosses.

Mosses have the most complex gametophytes of any of the land plants. Examine a moss gametophyte, and make a habit drawing. Notice that it looks superficially like the sporophyte of a vascular plant. There is a central stem-like axis from which extend several leaf-like structures. There is an apical growing point. There are root-like strands, the rhizoids, which anchor the plant in the ground. Examine the gametophyte carefully with the microscope and, with illustrations, show why the gametophyte actually does not have true stems, leaves, and roots. Gametophytes of most mosses develop from a stage, the protonema, that looks like a filamentous green alga. Find and draw a protonema and indicate how it can be distinguished from a green alga.

Find a gametophyte with a sporophyte(s) attached. Make a habit sketch of the sporophyte, labelling the seta and sporangium. Pull the sporophyte out of the gametophyte and draw the foot. The capsule may be covered with a filmy cone of tissue, the calyptra. Remove the calyptra, if present and examine the capsule in detail. Draw the operculum and peristome, and draw some spores from the inside of the sporangium. Find and draw where stomata are present on the sporophyte.

It may or may not be possible to find gametangia on the gametophytes of living mosses. Archegonia may often be found in the axils of "leaves" near the base of a sporophytes. Dissect out this region, and look for and draw archegonia under the microscope. Mosses have the structurally most complex archegonia of all the land plants. If no archegonia are present on living mosses, there will be a demonstration set up from preserved plants. It is unlikely that antheridia will be present on any living mosses, so a demonstration will be set up. Draw the arrangement of antheridia in an antheridial head, and draw a mature antheridium in detail.

Examine a specimen of peat moss, Sphagnum sp., and make a habit drawing. Mount a single "leaf" under the light microscope and draw it. What is it about peat moss that makes it so valuable a commodity?

Liverworts.

The gametophytes of some liverworts will be on display. Make habit drawings of them. Indicate whether each is a thallose or a leafy liverwort.

Hornworts.

Examine and draw the simple gametophyte of Phaeoceros laevis. What other land plant gametophytes does it remind you of? Why? How is more like a green alga than other land plants? (You need to use the microscope to answer the last question.) Examine and draw the sporophyte of this plant if present. How is it similar to the sporophytes of mosses? How is it different?


VIc. "Fern Allies", the Lycopods and Horsetails

Several groups of vascular plants evolved at approximately the same time as the ferns, and many of them had a similar life cycle to the ferns. That is, they had free-living sporophytes and free-living gametophytes. Of these plants, two divisions still have a few extant species. These divisions are the Lycophyta, or lycopods, and the Sphenophyta, or horsetails. We will examine the sporophyte stages of some representatives of these divisions in this exercise.

Lycopods.

The extant lycopods are all characterized by having microphyll leaves which typically have a single vein. The club mosses are classically placed in the single genus Lycopodium, though modern taxonomists are, as your text points out, dividing it into several genera. This group of lycopods, like the ferns and mosses you observed, produces one kind of spore which germinates to give rise to a single type of gametophyte that develops both antheridia and archegonia. Such plants are termed homosporous. The spike mosses of the genus Selaginella and the quillworts of the genus Isoetes produce two types of spores: large megaspores and small microspores. The former produce megagametophytes, and the latter produce microgametophytes. Megagametophytes support only archegonia, and microgametophytes support only antheridia. Plant with these two types of spores are termed heterosporous. We will examine fertile sporophytes of a clubmoss and a spikemoss.

Lycopodium.

Examine and draw a sporophyte of Lycopodium. Note the vegetative portion of the plant and the cone, or strobilus, which contains sporophylls that support sporangia. Observe that all the sporangia and their spores are of approximately the same size. Watch what happens when Lycopodium spores are tossed into an open flame. What does this tell you about spores?

Selaginella.

Examine and draw a sporophyte of Selaginella. Observe that the cones, if present, contain sporangia of different sizes and colors. How many spores are in a megasporangium? A microsporangium?

Fossil Lycopods.

Observe the specimens of Carboniferous lycopods. How did some of them differ from extant lycopods?

Horsetails.

All extant horsetails are classified in the single genus Equisetum. They are also commonly known as scouring rushes (why?). Examine sporophytes of E. hyemale noting the quality of the leaves stems roots and cones. The cones support specialized branches, the sporangiophores, that bear several sporangia each. Are these plants homosporous or heterosporous? Why? The leaves of horsetails are very small and look like microphylls. Examine a fossil horsetail, Sphenophyllum, and explain why horsetails have megaphylls as vegetative leaves.


VId. Seed Plants, the Cycads, Ginkgo, Conifers, Gnetophytes, and Flowering Plants.

All seed plants are heterosporous and have gametophytes that "germinate" from spores and complete their development in the tissue of the sporophyte generation. Their gametophytes are the simplest of all land plant gametophytes, and their sporophytes are the most complex. The microgametophytes germinate from spores in the microsporangium, are moved to female tissue as pollen, and complete development in the female tissue that supports the megagametophyte. Microgametophytes lack antheridia and produce only two sperm each. The megagametophyte develops within the megasporangium, or nucellus. The nucellus is protected in a specialized covering called the integuments. The combined integuments, nucellus, and megagametophyte are termed the ovule. The ovule remains attached to the parent sporophyte until it has matured into a seed. The sporangium-bearing structures of seed plants are often arranged on modified shoot tips called cones.

Gymnosperms.

This informal grouping includes the divisions of seed plants in which the ovule is directly exposed to the outside environment. These divisions are the Cycadophyta, the Ginkgophyta, the Coniferophyta, and the Gnetophyta. Although these divisions each have a number of distinctive features, their life cycles are similar enough that we will mix and match the "business ends" of each, that is, the ovules, microsporangia, and the pollen. All gymnosperms have pollen that consists of several cells and is produced in cone-like microstrobili. All have pollen that matures within the ovule by producing a pollen tube and two sperm. All gymnosperms have megagametophytes that consist of thousands of cells, and all but some of the gnetophytes have eggs produced in archegonia.

Conifers.

On your own, draw a habit of a sporophyte of a species of Pinus. Note how the leaves are bundled on short branches, the fascicles. This is a characteristic of this important genus of conifers. In lab, draw the dried male cones that matured earlier this spring. Label the pollen sacs (=micorsporangia). Examine and draw some pollen grains. Draw the female cones that were produced this spring, the female cones that were produced last spring, and the female cones that are two or more years old. Find the ovules in the cones from last year and the seeds in the mature cones.

Ginkgo biloba.

This is the only extant species in its division. Make a habit drawing on your own time of the sporophyte of this plant. In lab,examine and draw dried male cones. Examine and draw an ovuliferous appendage and an ovule developing into a seed. Make a longitudinal section of an ovule and draw the integument, nucellus, megagametophyte, and (if present) the archegonia.

Cycads.

Make a habit drawing of a sporophyte of Zamia pumila. in the greenhouse. Notice its fern-like appearance. We will use this plant as our example for gymnosperm male and female cones, pollen and ovules. Sketch a male cone and a female cone. How do they compare to each other. Break a male and female cone in half and draw and compare the male and female sporophylls. Crush a microsporangium on a slide and draw the microspores and or pollen you find. How do the spores compare to the pollen? Make a longitudinal section of an ovule and identify the integuments, nucellus, and megagametophyte.

 

Angiosperms.

The flowering plants are found in the single division Anthophyta. Unlike the other seed plants which are all woody, many flowering plants are herbacious. The distinctive feature of the flowering plants is that megasporophylls that produce the ovules completely seal the ovules in a closed chamber called the carpel. A flower may have one or more megasporophylls which may be separate from each other or fused together. The megasporophylls of a flower form one or more pistils (not pistols), each of which contains the carpel(s) in the ovary, a style through which pollen tubes (microgametophytes) grow to reach the ovules, and a stigma to which pollen sticks and germinates if it recognizes the correct chemical signal.

Your Flowering Plant.

Make a habit sketch of the plant you are using for your flower to fruit exercise. Draw and label flower buds, mature flowers, and maturing and mature fruits. Make free hand sections of each. In each case identify the flower parts that are present at each stage. Include the sepals, petals (or tepals), stamens, and pistil(s). Label the parts of the stamens and pistils that are present at each stage. In the stamens, include the filament and anthers. In the pistils include the stigma(ta), style(s), ovary(ies), carpel number per ovary, and ovules/seeds. If your seeds mature, indicate the embryo in the seed.

Lilium michiganense.

From the demonstrations of this flowering plant draw a cross section of an anther with mature pollen, an example of a mature microgametophyte, a mature megametophyte (or embryo sac), and a fertilized megagametophyte.

Capsella bursa-pastoris.

From a demonstration slide draw a seed with a mature embryo and endosperm. Label the parts of the seed that were the integuments, the nucellus, and the megagametophyte. How is this seed different from the seed of a gymnosperm?

Fruit.

During the final exam, feel free to eat some of the different fruits that will be present. Don't worry if you can identify all the parts.


Embryophytes (Land Plants) II: the Bryophytes: Checklist for Notebook

Mosses, Mnium sp., Atrichum sp., Polytrichum sp., use fresh material and/or prepared slides. Make sure you illustrate all the stages. You may use whatever combination of specimens you wish.

Somatic diploid, the dependent sporophyte

___x__Habit of sporophyte attached to gametophyte, Label, __x__capsule (=sporangium), __x__calyptra (=old archegonium), _x___operculum, __x__seta, _o___foot (pull out of gametophyte)

Site of meiosis and products of meiosis, the sporangium and spores

__x___Details of sporangium using 4x, 10x, and/or 40x objectives on compound scope, Label, __x__operculum, __o__peristome and peristome teeth, __o__stomata in epidermis of capsule, __x__spores showing __o__triradiate ridge

Somatic Haploid, the independent gametophyte

__x___Habit of "leafy" gametophyte, Label, ___x_rhizoids, __x__stem-like axis, __x__"leaf"

Sites of gamete development and fertilization, the gametangia

__x___Splash cup of male gametophyte, use dissecting scope, and 10x and 40x, Label __x__"leaves" that form walls of the cup, __x__central region containing antheridia, __x__sterile filaments, _____young antheridia with spermatogenous cells and sterile jacket, _x___mature antheridium with sterile jacket, ____sperm release, ____released sperm.

__x___Female gametophyte with attached sporophyte (may be same as above), use dissecting scope, and 10x and 40x, Label, _x___archegonium with ___x_stalk, __x__venter, _x___egg, __x__neck, __x__neck canal, __o__neck canal cells, __o__attachment of foot in old archegonium

Liverworts, Somatic Haploid, the independent gametophytes

Thallose liverwort, Pallivicinia sp.

____x__Habit showing ___x_photosynthetic thallus with __x__midrib, __x__site of gametangium development, __x__rhizoids

Leafy liverwort, Porella sp.

___x__Habit showing __x__"leafy" gametophyte axis, __x__midrib

Hornworts, gametophyte with sporophyte, Phaeoceros laevis

__x___Habit of gametophyte with attached sporophyte, Label, _x___gametophyte with __x__involucre, __x__somatic cell with single plastid,__x__symbiotic Nostoc colony, _x___sporophyte, with, __x__sporangium (=capsule)


Embryophytes (Land Plants) III: the Seedless Vascular Plants: Checklist for Notebook

Lycophytes, the clubmosses (Lycopodium spp., s.l.), spikemosses (Selaginella spp.), and quillworts (Isoetes spp., not seen). Use preserved and fresh material and/or prepared slides. Make sure you illustrate all the stages. You may use whatever combination of specimens you wish.

Homosporous, nonligulate lycophytes Huperzia (Lycopodium) lucidulum

Somatic diploid, the independent sporophyte

__x___ Habit of sporophyte of all available species, Label, __x__stem, __x__microphyll leaf, __x__adventitious root, ____cone (if present), __x__sporophyll and sporangium (if present), detail of leaf wet mount showing _o___xylem in single vein, __o__stoma

Heterosporous, ligulate lycophytes Selaginella apoda, S. rupestris,

Somatic diploid, the independent sporophyte

__x___Habit of sporophyte of all available species, Label __x__stem, __x__microphyll leaf, __x__adventitious root on rhizophore, __x__cone (if present), detail of leaf wet mount showing __o__xylem in single vein, _o___ligule, __o__stoma

The site of meiosis and products of meiosis, the spores (live material and prepared slide)

___x__Detail of cone showing __x__microsporophyll and __x__microsporangium and __x__megasporophyll and __x__megasporangium, __x__detail of microsporangium showing __x__microsporophyll, ___x_microsporangium wall, __x__microspores, __x__detail of megasporangium showing __x__megasporophyll, ___x_megasporangium wall, __x__single tetrad of megaspores, ____detail of developing sporangium showing ____sporangium wall, ____tapetum, ____sporogenous tissue

Horsetails, Equisetum hyemale. Use fresh material. Make sure you illustrate all the stages.

Somatic diploid, the independent sporophyte (live specimen)

__x___Habit of the sporophyte showing aerial stem with __x__nodes, __x__internodes, __x__whorls of scale-like megaphyll leaves, __x__cones (if present), __x__branches (if present), __x__rhizome with __x__whorles of leaves at node, __x__adventitious roots

The site of meiosis and products of meiosis, the spores

__x___Detail of cone showing __x__central axis, __x__sporangiophores, __x__sporangia with __x__sporangium wall, __x__spores, __x__detail of spore with __x__elaters


Embryophytes (Land Plants) IV: the Seed Plants I: The Sporophytes: Checklist for Notebook

Cycads, Zamia furfuracea

__x___Habit male and/or female plant (draw reproductive structures of both plants), Label, _x___stem, __x__pinnately compound leaf, __o__coralloid root, __x__male cone, __x__female cone

Ginkgophytes, Ginkgo biloba

__x__Habit male and/or female tree (draw reproductive structures of both plants), Label, _x___stem, __x__spur branches, __x__leaf, ___x_unrolling leaf, __x__male cones (dried), __x__ovuliferous appendages (female tree), __x__ovules/developing seeds, ____pollination droplet on ovule

Conifers, Pinus spp.

__x___Habit tree, Label, __x__stem, ___x_1998 leaves, __x__1999 leaves, __x__new 2000 leaves, __x__fascicle of leaves (needles), __x__male cones, __x__1998 or older, female cones, __x__1999 female cone, __x__2000 female cone, ____pollination drop

Flowering plants, Your flower to fruit plant

__x___Habit, Label, __x__roots, __x__stem, __x__leaves, __x__flower bud, __x__open flower with __x__sepals, __x__petals (tepals if petals and sepals look alike), __x__stamens, __x__pistil(s), __x__fruit

Supplement with drawings of any specimens brought to class


Embryophytes (Land Plants) IV: the Seed Plants II: Microsporophylls and Pollen Development: Checklist for Notebook

Cycads - Not Covered

Ginkophytes, Ginkgo biloba

___x__Male cone, Label, __x__axis, __x__microsporophyll, __x__pollen sacs (=microsporangia), ____immature pollen grain (40x objective) with ____prothallial cells, ____generative cell, and ____tube cell, __x__mature pollen grain

Conifers, Pinus spp. ( dried material and prepared slide and lecture demo)

__x___Cluster of male cones at base of 2000 growth, __x__male cone, Label, __x__microsporophyll, __x__pollen sacs (=microsporangia), __x__pollen, __x__section of male cone (4x, 10x, and 40x), Label, __x__microsporophyll, ___x_pollen sac, __o__microspore with one cell, __x__developing pollen undergoing mitosis, __o__mature pollen with __o__prothallial cells, __o__generative cell, __o__tube cell, __x__living pollen (40x), Label, __x__air sacs, __x__pollen grain (and cells if seen)

Flowering plants, your plant and Lilium michiganense (demo in lecture)

__x___Androecium (all the stamens) of your plant, Label, ___x_stamen (=microsporophyll) with __x__filament, __x__anther with __x__connective, ___x_4 pollen sacs(=microsporangia), __x__pollen (40x) showing __x__pollen grain wall, __x__tube cell, ___x_generative cell

__x___Transverse sections of androecium of Lilium, Label __x__anthers with __x__connective and __x__4 pollen sacs, detail of pollen sac through pollen development showing __x__pollen sac wall, __x__tapetum (in early stages), __x__microspore mother cells, __x__meiosis I, __x__meiosis II or dyad, __x__tetrad of microspores, ____pollen development, __x__mature pollen with __o__ generative cell and __o__tube cell


Embryophytes (Land Plants) IV: the Seed Plants III: Ovules, Megagametophytes, Microgametophytes, and Seed Development: Checklist for Notebook

Gymnosperm ovules

Ginkgo biloba ovule with megagametophyte and microgametophyte

__x___Habit of ovuliferous appendage, Label, __x__appendage in situ on spur branch, __x__pair of ovules/developing seeds, __x__integuments, __x__micropyle, ____pollination drop

__x___Freehand section of ovule/seed, Label, __x__integument, __x__micropyle, __x__nucellus (megasporangium) with __x__pollen chamber, __o__microgametophyte(s), __x__megagametophyte

Pinus sp. female cones with ovules

__x___Habit, 2000 (first year) cone, Label, __x__scale, __o__pollination drop

___x__Prepared section of first year cone, Label, __x__ovuliferous scale, __x__ovule with _x___integuments, __x__micropyle, __x__premeiotic nucellus (megasporangium), __o__pollen grain

___x__Habit, 1999 (second year) cone, Label, __x__scale (draw to scale with 2000 cone)

__x___Freehand section of second year cone and prepared section of second year ovule, Label where appropriate on each, __x__ovuliferous scale, __x__ovule, __x__integuments, __x__micropyle, __x__nucellus (megasporangium), __x__pollen tubes of microgametophytes growing through nucellus, __x__megagametophyte with __x__somatic tissue, __x__archegonium(a), __x__egg(s)

__x___Habit, mature cone, Label, __x__ovuliferous scale, __x__winged seed

Flowering plants, ovaries, ovules, fruits and seeds

Your plant and plants in lab

__x___Pistils of buds, mature flowers showing __x__stigma, __x__style, __x__ovary,__x__carpel(s) __x__ovule with __x__integument, __o__micropyle, __o__nucellus, __x__embryo sac with __o__egg apparatus, __o__central cell, __o__antipodals

__x___Developing and mature fruits (identify fruit type if possible, see text of one us) showing __x__fruit wall, _x___carpels, __x__developing and mature seeds, __o__embryo in seed

Lilium sp. from slide demo in lecture

__x___Developing microgametophytes (fooled in sugar water) showing __x__ pollen grain wall, __x__pollen tube with __x__tube cell, __x__tube cell nucleus, __x__ two sperm

___x__Section of young ovule with __x__developing integument, __x__nucellus with __x__megaspore mother cell

___x__Section of mature ovule with embryo sac showing, __x__integuments, __x__micropyle, __x__nucellus, __x__megagametophyte (embryo sac) with __x__three antipodal cells, __x__central cell with __x__polar nuclei, __x__three egg apparatus cells (egg, and synergids)

__x___Section of ovule immediately after fertilization with parts of the ovule labeled plus __x__fertilization of the egg (=zygote formation) and __x__fertilization of the central cell to form the primary endosperm

Seed development in Capsella bursa-pastoris from lecture demo, prepared sections

__x___Young seed with __x__ seed coat including integuments and nucellus, _x___free nuclear (coenocytic) endosperm, __x__embryo with __x__suspensor and __x__embryo proper

__x___Older seed with __x__seed coat, __x__endosperm, __x__embryo with __x__suspensor, __x__young embryo with developing cotyledons and primary root axis

__x___Mature seed with __x__seed coat, __x__cellular endosperm, __x__embryo with primary root, cotyledons, and primary shoot axis


Flower to Fruit Exercise and Checklist of Biological Principles that have been discovered in Botanical Critters: Checklist for Notebook

Flower to Fruit (see above as well)

___x__Habit of your plant, Label __x__the name of the plant, ___x_roots, __x__stem, __x__leaves, __x__flower bud, _x___mature flower, ___x_developing fruit, __x__mature fruit

__x__Flower bud, Label, __x__sepals, __x__petals, (or __x__ tepals), __x__stamens with __x__filaments and __x__anthers, __x__pistil(s) with __x__stigma, __x__style, __x__ovary, __x__carpel(s), __x__ovules (if present)

__x__Mature flower, Label, __x__sepals, __x__petals, (or __x__ tepals), __x__stamens with __x__filaments and __x__anthers, __x__pistil(s) with __x__stigma, __x__style, __x__ovary, __x__carpel(s), __x__ovule(s), __x__embryo sac - Also do this for the cherry from your kit

__x___Developing fruit, Label, _x___sepal, petal, and stamen scars, __x__old stigma and style, __x__ovary/fruit, __x__carpel(s), _x___developing seed(s)

__x___Mature (as possible) fruit, Label, __x__fruit type, __x__fruit wall, __x__carpel(s), __x__ seed(s), __x__endosperm, __x__embryo - Also do this for the cherry and the lily from your kit

Checklist of Principles

I expect that you should have at least 20 entries on this list. It's really easy to find 40-50 good ones, and I have had one student turn in over 100 (some of which are real stretches).


End of Summer Instructions
BOTY 2404, Survey of the Plant Kingdom, Spring, 2000

Instructor: Dr. Fred Spiegel, SCEN 529 (then 711), phone: 575-6343, email: fspiegel@comp.uark.edu, Homepage: http://comp.uark.edu/~fspiegel/

Office hours: MTWR - 8-8:45 and by appointment

Text: Raven, Evert, and Eichhorn, Biology of Plants, 6th Ed. This is an excellent book that you can also use as a reference to remind you of the principles of biology that are fundamental to this course. You may also use Moore, Clark, and Vodopich, Botany, 2nd Ed. if you wish. This is the text that is used in BOTY 1613. Many reference books will be available in the lab as well.

Supplies: A 3-ring binder, plenty of Botany Paper, a 3H pencil (or drawing pen, or colored pencils), a good eraser, and a Botany Kit (shared by 2-3) which can be purchased at the UofA Bookstore in the Union.

Class and Grading Policies: Lab and lecture material will complement each other. Come each day ready to start each scheduled activity. Grades will be based on: 1) two semester exams and a final exam (@ 60%) and 2) your lab notebook and completion of two semester projects (@40%). All exams will be based on questions asked from a set of projected slides which you will be able to study in advance. The final exam will include a scavenger hunt. All exams are comprehensive in nature. See Recommended Study Aid below. Your lab notebook will consist of drawings and answers to questions given in the different lab exercises. Lab assignments for the semester are described below. You are expected attend all classes and labs. Because labs may involve walking field trips to collect specimens, always come prepared to go outside; i.e, wear appropriate clothes and shoes.

The grading scale on the exams is as follows:

I reserve the privilege of lowering the cutoff for exam grades but I will never raise them. That is, a 68% will never be a B or lower, but I might decide that a 51% is a D.

Lab notebooks will be graded based on completeness of your coverage of organisms seen in class, the inclusion and quality of your Flower to Fruit Exercise (see below), and the inclusion of your List of Principles (see below). Completeness of coverage means inclusion of your original drawings of organisms with appropriate labeling. There will be a checklist against which to evaluate your completeness of coverage (see below).

Weather Policy: As long as the University is open, class will meet. If we experience inclement weather in Northwest Arkansas such that you feel that it is unsafe for you to attend, you should not put yourself at risk. I will reschedule any exams scheduled on days when weather creates a travel risk.

Semester Lab Assignments:

1. Compile a list of fundamental biological concepts or principles that have been discovered and/or illustrated using botanical organisms. Example:

Principle

Discoverer

Organism or group of organisms

Organisms made of Cells

Hooke

Cork Oak (Quecus suber)

2. Flower - to - Fruit. Find an angiosperm that is flowering and producing fruit. Illustrate the development of the flower and the fruit from the flower bud stage to the mature fruit stage. Illustrations should be drawings or photographs. (See me if you wish to do the latter.) Do not shortchange this exercise by waiting until the last minute. You should be well under way by mid March. Also, illustrate as many stages of development as you can. You cannot overdo this project. We will take several field trips in February and March to show you plants that will work well as subjects.

3. Lab Notebook. Prior to each lab, the instructions for that lab will be posted on this page. Download them, and read them before lab meets. The notebook should be laid out as follows:

To aid you in keeping track of what we actually cover in lab, there will be a set of checklists posted below to let you know which organisms should be drawn in your notebook and what structures should be labeled. Any entry marked with x will be something you should have included. Any entry marked with o indicates something that many people saw. If a subject is left blank, it means our plans did not work out. Sometimes the checklist will include examples that were not on the lab instructions because something good came up.


Topic Coverage

Tentative Schedule of Topics (Certain organisms may occur in abundance in lab collections before or after we are scheduled to cover them; therefore, we may cover them out of order. I will give you specific instructions in those cases)

Week of Topics Suggested Reading and Assignments

Week of

Topic

Suggested Reading and Assignments

18 Jan

Spiegel out of town; purchase books, supplies

Ch. 13, 14 thru p. 296

25 Jan

Introduction, Modern Systematics, Cyanobacteria

Ch. 13, 14 thru p. 296; bring pond-bottom and water samples to lab

1 Feb

Introduction to Eukaryotes; Introduction to Stramenopiles (aka Heterokonts)

Ch. 17 thru p. 385; bring in more pond-bottom and water samples to lab

8 Feb

Stramenopiles continued

Ch. 17 thru p. 385; bring in more pond-bottom and water samples to lab

15 Feb

Stramenopiles concluded, Miscellaneous Protist Algae (Euglenoids, Dinoflagellates, Cryptomonads)

Ch. 17 thru p. 385, Ch. 16, pp. 348-352, 356-357, 361-366; bring Fucus from Kits and pond bottom and water samples and dry soil samples to lab

22 Feb

Exam I, Thu., 2/24 (thru Cyanobacteria and Stramenopiles); MPA, continued, Mycetozoans

Ch. 16 as above and pp. 352-356; bring pieces of dead plants to lab

29 Feb

Fungi

Ch. 15; Bring Rhizopus, lichens, and mushroom from Kits, and any cool fungi you find in the fridge to lab

7 Mar

Fungi concluded, Red Algae

Ch. 15 and 16, pp. 357-362

14 Mar

Red Algae

Ch. 16, pp. 357-362. Turn in notebooks for progress check on Thursday, 16 Mar.

21 Mar

SPRING BREAK

Bring back cool stuff for lab

28 Mar

Green Algae

Ch. 17, pp. 383-398; bring pond bottom and water samples to lab

4 Apr

Exam II, Thu., 4/6 (thru Red Algae) Introduction to land plants, the Ferns as exemplars; Introduction to nonvascular plants (aka Bryophytes)

Ch 19, pp. 449-463 and Ch. 18; bring fern, moss, and liverwort from Kits to lab.

11 Apr

Bryophytes concluded, Horsetails and Lycophytes

Ch. 18 and Ch. 19, pp. 425-449; bring horsetail (Equisetum) and club moss from Kits to lab

18 Apr

Introduction to Seed Plants, habit and pollen producing structures

Ch. 20-22, bring Pine, Lily, and Cherry from Kits to lab.

25 Apr

Seed Plants, ovules, microgametophyte maturation, fertilization, seed development, and fruits

Ch. 20-22

2 May

Review

Scavenger Hunt in Thursday Lab

Wed, 5/10

Final Exam, 12:30 - 2:00

Notebooks due at beginning of exam


Recommended Study Aid. You should construct a table of the major groups of organisms we study in the course. It may include your own drawings and written information. You may not include any xeroxed information. I suggest that you construct this as a table, and in the case of all the groups of eukaryotes, you should arrange the columns in the following life cycle order:

For some eukaryotes we will study only a single somatic state, so a life cycle would not be appropriate. You may bring this table to each exam. For the first exam, it may not exceed two sides of 8.5x11 paper. For the second exam, no more than 4 sides. For the final, no more than 6 sides.


Stuff to Know for BOTY 2404, Spring 2000

This list may change as the semester goes along. It is a starting point. Everything in red is stuff you need for the first exam. Everything in red and blue is stuff you need for the second exam.

General: Know the terms in bold type in your lab instructions. Life cycles marked with * are illustrated in your text.

Cyanobacteria: Thylakoid, phycobilisome, photosynthetic pigments, gas vacuole, cell wall, unicellular thallus, colonial thallus, filamentous thallus, false-branching thallus, branching thallus, heterocyst, akinete, stromatolite, cyanobacterial mat

Eukaryotes: Nucleus, mitosis, meiosis, sex, gamete, zygote, endosymbiosis, organelle, flagellum(a), coenocytic vs. uninucleate thalli, ploidy, pyrenoid, isomorphic vs. heteromorphic alternation of generations, sporophyte vs. gametophyte, gametangium, isogamy vs. anisogamy vs. oogamy

Stramenopiles: Whiplash vs. tinsel flagellum, photosynthetic pigments (when present), unicell, motile unicell, colony, motile colony, filament, mitochondrial morphology

Simple Stramenopile Algae: Chrysophyceae, Xanthophyceae, Bacillariophyceae, Diatoms, plastid structure, lorica, cell wall, frustule, centric vs. pennate diatom, valve vs. girdle

Oomycetes: Hypha, zoosporangium, zoospore, antheridial branch, antheridium, fertilization tube, oogonium, egg (oosphere), oospore (zygote), Saprolegniales, Peronosporales

Phaeophyta, Brown Algae: Plurilocular gametangium, plurilocular zoosporangium, unilocular zoosporangium, kelp, holdfast, stipe, blade, kelp oogonium, kelp antheridium, kelp zoosporangium, Fucus oogonium, Fucus antheridium

Euglenoids: Euglena, Pellicle, Paramylon, Reservoir;

Dinoflagellates: Peridinium, Cingulum, Sulcus

Myxomycetes: Fruiting body, Spore, Amoeboflagellate, Plasmodium

Dictyostelid Cellular Slime Molds: Fruiting body, Spore, Amoeba, Aggregation, Slug

Fungi General: Hypha, Mycelium, Monocentric thallus, Yeast, Dikaryon

Chytridiomycetes: Monocentric chytrids, Zoosporangium, Zoospores, Rhizoids, Allomyces, Male and Female Gametangia, Zoosporangia, Resting sporangia.

Zygomycetes: Mucorales, Sporangium, Sporangiophore, Zygospore, Pilobolus, Rhizopus.

Ascomycetes: Ascus, Ascospore, Fruiting body, Apothecium, Perithecium, Conidium, Conidiophore, Saccharomyces, Lichen

Basidiomycetes: Agarics, Mushroom, Cap, Stipe, Gill, Basidium, Basidiospore, Rust, Telium,Teliospore, Spermagonium, Spermatium, Aecium, Aeciospore.

Red Algae: Florideophyceae, Polysiphonia, Male and Female Gametophytes, Tetrasporophyte, Carposporophyte, Spermatangium, Spermatium, Carpogonium (=Egg), Cystocarp, Carpospore, Carposporangium/carpospore, Tetrasporangium/tetraspore

Life Cycles to Know: Vaucheria, Saprolegnia*, Ectocarpus, Fucus*, Kelp*,Myxomycetes*, Allomyces*, Rhizopus*, Filamentous Ascomycetes*, Filamentous Basidiomycetes*, Polysiphonia*

Green Algae: Chlorophyceae, Ulvophyceae, Charophyceae, Thallus types, Chlamydomonas, Volvox, Chara, Spirogyra, Ulva, Zoosporangia, Zoospores, Gametes, Gametangia

Land Plants in General: Heteromorphic alternation of generations, Archegonium, Antheridium, Embryo, Spore mother cell, Spore, Triradiate ridge

"Bryophytes" in General: Dominant, free living gametophyte, Dependent sporophyte with single sporangium

Liverworts: Thallose vs. leafy liverworts, Marchantia, Reboulia, Pore, Rhizoid, Scale, Gemma, Gemma Cup, Antheridiophore, Sperm structure, Archegoniophore, Foot, Seta, Sporangium (aka Capsule), Spore, Elater, Determinate growth of sporophyte

Mosses: Protonema, Leafy gametophyte, Axis, "Leaf", Rhizoid, Polytrichum, Mnium, Sphagnum, Splash cup, Antheridial head, Archegonial head, Sperm structure, Foot, Seta, Sporangium (aka Capsule), Stoma, Peristome, Operculum, Determinate growth of sporophyte

Hornworts: Single plastid with pyrenoid, Algal symbiont, Rhizoid, Phaeoceros, Antheridial chamber, Simple archegonium, Involucre, Foot, Basal meristem, Sporangium, Columella, Indeterminate growth of sporophyte

Vascular Plants in General: Free living or dependent gametophyte, Gametophytes with reduced or absent gametangia, Dominant, free living sporophyte with xylem and phloem and, usually, stems with leaves (shoot) with nodes and internodes, and roots, and multiple sporangia, Rhizome vs root.

Lycopods: Microphyllous, Homosporous (Lycopodia) or Heterosporous (Ligulate lycopods), Cone (aka Strobilus), Sporangium with spores, Microsporangium with Microspores, Megasporangium with Megaspores, Bisexual gametophyte, Microgametophyte, Megagametophyte, Lycopodium, s.l, Selaginella, Isoetes

Horsetails: Megaphyllous, Small leaves in whorls, Node/Internode arrangement pronounced, Cone, Sporangiophore, Homospory, Elaters, Gametophyte, Sperm structure, Equisetum

Ferns: Megaphyllous, Leaves as fronds, Fiddlehead(aka Crozier), Sorus, Indusium, Annulus, Lip cells, Gametophyte, Position of gametangia, Sperm structure

Seed Plants in General: Megaphyllous, Woody or secondarily herbaceous, Heterosporous, Gametophyte development dependent, Microsporangium/Pollen Sac, Pollen Microgametophyte, Pollen tube, Two sperm, Ovule, Nucellus/Megasporangium, Megaspore -> megagametophyte, Seed

Cycads: Pinnately compound leaves, Trees or "shrubs", Dioecious, Male cones, Microsporophylls, Pollen sacs, Pollen structurem Sperm structure, Female cones, Megasporophylls, Ovules, Archegonia, Seed structure, Zamia, Cycas

Ginkgo: Trees with fan shaped leaves, Dioecious, Male cones, Microsporophylls, Pollen sacs, Pollen structure, Sperm structure, Ovuliferous appendages, Ovules, Archegonia, Seed structure

Conifers: Trees and shrubs, Monoecious or dioecious, Male cones, Pollen sacs, Pollen structure, Sperm structure, Female cones, Ovuliferous scales, Ovules, Archegonia, Seed structure, Pinus

Flowering Plants: Trees, shrubs, and herbs, "Dicot" vs monocot, Monoecious or dioecious, Flower, Sepal, Petal, Stamen, Anther, Pistil, Stigma, Style, Ovary, Carpel, Fruit, Pollen structure, Sperm structure, Ovule structure, Embryo sac/Megagametophyte structure, Double Fertilization, Endosperm, Lilium

Life Cycles to Know: Vaucheria, Saprolegnia*, Ectocarpus, Fucus*, Kelp*,Polysiphonia*, Myxomycetes*, Allomyces*, Rhizopus*, Filamentous Ascomycetes*, Filamentous Basidiomycetes*, Chlamydomonas (be able to apply this to any freshwater greens)*, Fern*, Moss*, Marchantia*, Lycopodium*, Selaginella*, Equisetum*, Pinus*, Flowering plant*.


Lab Exercises and Checklists

Keep track of these to add the exercises for the following week's labs. Each lab exercise will be followed by a checklist for that exercise. Keep checking the checklists in case a late breaking observation has been made. The checklists will be updated throughout the semester. All the instructions and checklists below should be included in your notebook. Note that bold faced terms and taxon names marked with * are terms with which you should become familiar. Usually these terms will be set off only the first time they are used during the semester.


Rules for the Lab in Plant Kingdom


Survey of the Plant Kingdom Laboratory, Introduction

Lab Notebook, Arrangement and Preparation of Drawings

Arrangement of Drawings. Your lab notebook will consist primarily of drawings of the organisms we encounter throughout the semester. Drawings must be in pencil (3H or colored pencil) or ink on Botany Paper, a 3 hole-punched, heavy, high quality drawing paper. The drawings of organisms must be arranged by exercise with the directions that cover each exercise. You must limit your drawings to one organism (genus) per page unless we explicitly tell you otherwise. You may add to a page when you encounter the organism repeatedly. Each page must identify the organism to genus (when possible) and have labels for all the important structures. Pay particular attention to terms that are in bold print in the directions to each exercise. Each page should include as many habit and detail drawings as is appropriate (see below).

The Habit Drawing. A habit (not habitat) drawing is a drawing of the whole organism, or a very large portion of the organism. The purpose of such a drawing is to give an idea of what the whole organism looks like and to arrange the drawing in such a manner as to show the important characteristics of the organism. In the habit drawing, you must learn to exercise some editorial control over yourself by learning to recognize that it is not necessary to draw lots of examples of repeated parts. The goal of the habit drawing is to make an accurate representation of the important aspects of the whole organism. Remember, pretty is not as important as accurate. Remember, a habit drawing may be of either a macroscopic or a microscopic organism.

The Detail Drawing. Detail drawings, as should seem obvious, are drawings of parts of an organism that are important and need to be highlighted. Remember, a detail drawing may be of a macroscopic or microscopic structure.

Introduction to Drawing. Several organisms will be available for you to draw. First you will make habit drawings of some macroscopic organisms. Make sure you draw all the obvious structures accurately. Draw lines to the structures that you think should be labelled. (You do not have to worry about actual labels at this point.) Next, make some detail drawings of macroscopic parts of the first organism you drew. Again, draw lines to the structures you think should be labelled. Next, make some drawings of material on prepared microscope slides. Make one drawing using the 10x objective (low power) and one of a detail using the 40x objective (high dry power). Add the indicator lines as above. Finally make a wet mount of one of the specimens that will be provided and make a low power and a high dry power drawing of something interesting. Remember to add the indicator lines.


Survey of the Plant Kingdom Laboratory

Exercise I - Cyanobacteria, the Bacterial Algae

Note: In the water and soil samples we have in class throughout the semester, there will be numerous algae from several different groups. We will focus on the groups of interest for the lab of the day. However, if we encounter particularly good examples of algae that we will study later or good examples from groups we have already covered, we may ask you to drop everything so that we can take advantage of the situation. It will be your responsibility to include this material with the correct exercises. Also, be sure to draw all organisms or structures marked with a asterisk (*) in every lab assignment, and be aware that you will be responsible for all terms marked in bold print.

Bacteria - Cyanobacteria. These are the only prokaryotic organisms we will study. Cyanobacteria are the Gram negative Bacteria which have evolved oxygen-generating photosynthesis. Many of them are also capable of fixing atmospheric nitrogen. Some have specialized cells for nitrogen fixation called heterocysts. Heterocysts may also act as propagules. Some bluegreens produce thick walled resting propagules called akinetes. Bluegreens are found in all types of habitats in which there is sufficient light and water for photosynthesis. We will find them in soil and water samples and focus primarily on the diversity morphology found in the group. Draw at least one example of each of the morphological types listed below.

Unicellular Forms*: Look for single cells or small groups of cells that are greenish but show no internal substructure.

Examples: Gloeocapsa sp., Chroococcus sp.

Colonial Forms: Look for clusters of cells with either a distinct shape or in an amorphous mass. They will typically share a common sheath.

Examples: Microcystis sp., Gomphosphaeria sp., Merismopedia* sp (prepared slide), Coelosphaerium sp..

Filamentous Forms:

Simple Unbranched Filaments: Examples: Oscillatoria* sp., Lyngbya sp.

Unbranched Filaments with Heterocysts and/or Akinetes: Examples: Anabaena* sp., Cylindrospermum sp.

Colonies of Unbranched Filaments: Examples: Nostoc *sp. (with heterocysts), Microcoleus sp. (without heterocysts), Aphanizomenon sp.(with heterocysts)

Tapered Filaments*: Examples: Calothrix sp., Gloeotrichia sp.

Colonies of Tapered Filaments: Example: Rivularia sp.

Pseudobranched Filaments*: Examples: Tolypothrix sp., Scytonema sp.

Branched Filaments: Example: Stigonema* sp. (prepared slide)


Cyanobacteria: Checklist of Bluegreens for Lab Notebook

Unicellular Cyanobacteria

_____Synechocystis sp., Label _____cell

__x___Gloeocapsa sp. and/or Chroococcus sp., Label __x__cell, ___x_sheath

Colonial Cyanobacteria

___x__Merismopedia sp. (prepared slide), Label __x__cell, __x__dividing cell, ___x_sheath

___o__Coelosphaerium sp. and/or Gomphosphaeria sp., Label __o__cell, __o__gas vacuoles, __o__sheath

Simple, Unbranched Filamentous Cyanobacteria without Heterocysts

__x___Oscillatoria sp., Label __x__cell, __x__dividing cell, __x__separation cell

Unbranched Filaments with Heterocysts and/or Akinetes

_____Anabaena sp., Label ____cell, ____dividing cell, ____heterocyst, _____ akinete (if seen)

_____Cylindrospermum sp., Label ____cell, ____terminal heterocyst, ____subterminal akinete

Colonies of Unbranched Filaments

___x__Microcoleus sp., Label ___x_filaments, __x__common sheath

___x___Nostoc sp., Label __x__filaments with heterocysts, ___x_common sheath

___o__Aphanizomenon sp., Label __o__filaments, ___o_gas vacuoles

Tapered Filaments

__x __Calothrix sp. or Rivularia sp., Label __x___cell, __x__terminal heterocyst, __o__sheath

Pseudobranched Filaments

__x___Scytonema sp. and/or Tolypothrix sp., Label __x__cell, __x__heterocyst, __x__sheath, __x__false branch

Branched Filaments

__x___Stigonema sp. (prepared slide), Label __x__cell, __o__heterocyst, __x__sheath, __x__branch

Cyanobacteria you might have seen and drawn

Lyngbya sp., Spirulina sp.


Survey of the Plant Kingdom Laboratory

Exercise II - The Stramenopiles

Stramenopiles I - Chrysophytes, Xanthophytes, and Diatoms

The stramenopiles are a large, monophyletic group of eukaryotes which to some extent "mimic" the evolutionary trends seen in the botanical members of the FAP (Fungi, Animal, Plants) eukaryotes. There are microscopic, simple photosynthetic stramenopiles. There are complex, multicellular, photosynthetic stramenopiles, and there are lysotrophic, fungus-like stramenopiles. (There are also some nonpigmented "protozoan"-like stramenopiles, but we will not talk about them.) The easily recognized derived character that unifies the group is the presence of tripartite flagellar hairs (aka, mastigonemes) on the anteriorly directed flagellum, the tinsel flagellum, of flagellated cells. If there is a second flagellum on a cell, it is posteriorly directed and without hairs; such a flagellum is called a whiplash flagellum. (Nonflagellated members of the group can be included on the bases of other characters, but we will not worry about them here.)

This part of the exercise focuses on the simple algal members of the stramenopiles. They are covered in Chapter 17 of your text. The informal names for these organisms are the chrysophytes (including the classes Chrysophyceae and Synurophyceae), the xanthophytes (class Xanthophyceae or Tribophyceae), and the diatoms (class Bacillariophyceae). Most of these algae are morphologically simple. They are either motile or nonmotile unicells, motile or nonmotile colonies, or branched or unbranched filaments. The filamentous forms may be multicellular or they may be large multinucleate unicells called coenocytes. Some of these organisms have relatively complex life cycles, but we will not be concerned with them except in the case of the xanthophyte, Vaucheria. Rather, we will focus on the habits of the primary somatic states of these algae.

Chrysophytes. Most of these algae aquatic and prefer cold water, so they will be present primarily early in the semester. Examine and draw examples of chrysophytes with the morphological types listed below.

Motile Unicells: Ochromonas sp., Mallomonas* sp.

Motile Colonies: Dinobryon* sp., Synura* sp., Uroglena sp.

Characters to label include: plastids, eyespots (if present), loricae (if present), scales (if present), and flagella. Label the nuclei where visible. You will not be able to see flagellar hairs, so do not draw them.

Diatoms. Most local diatoms are nonmotile (i.e., nonflagellated) unicells. Some are nonmotile colonies, and a few are filamentous. They are found in soil, on rocks, on aerial portions of plants, and in water. Some live on solid surfaces, and some are planktonic. All diatom cells have two overlapping sets of silica shells called frustules. The frustules form in vacuoles just under the plasma membrane of the cell. From the side, in girdle view, all diatoms look something like a petri dish. From the top or bottom, in valve view, there are two major shapes that define two morphological groups of diatoms, the radially symmetrical centric diatoms and the bilaterally symmetrical pennate diatoms. Examine and draw at least one species of diatom in both valve and girdle view. Label the nucleus, plastids, central vacuole, mitochondria, and characteristic structures of the valve.

Draw examples of the following morphological types.

Centric Unicells: Stephanodiscus* sp.

Pennate Unicells: Navicula* sp., Nitzschia sp., Cymbella sp.

Nonmotile Colonial Diatoms (all pennate): Asterionella* sp., Fragillaria* sp., Gomphonema sp.

Filamentous Diatoms (centric): Melosira* sp.

Xanthophytes. The only example of this group we will examine is the terrestrial genus Vaucheria*. Look for a felt-like, bright green mat on the surface of moist soil. It should be somewhat sparkly in appearance and feel somewhat rough to the touch. This is probably Vaucheria sp. Carefully wash some of the filaments of this alga from the soil and mount them on a slide in a drop of water. Gently lower a coverslip onto this prep and observe and draw the branched, coenocytic filaments of this alga. The only structures easily seen in the filaments are the plastids and the central vacuole. Examine your filaments for sex organs. An oogonium is somewhat ovate with a single large egg. Antheridia are curled and often close to oogonia in the species we commonly encounter around here. When flagellated sperm from the antheridium fertilize an egg in the oogonium, a thick walled zygote develops. Draw the sex organs you find. The filaments of Vaucheria are diploid. Where does meiosis occur in the life cycle of this alga?

Other xanthophytes we might encounter include the unbranched filamentous Tribonema, the branched colonial Mischicoccus with its spherical cells, and the unicellular epiphytic Characiopsis with its spindle shaped cells. Draw these if you encounter them.

Other Simple Stramenopile Algae. We may encounter a large, heart shaped intensely green flagellate that appears to have a very large nucleus associated with the base of the flagella. This is the chloromonad Gonyostomum. Draw it if you encounter it.


Stramenopiles II - The Oomycetes

The oomycetes are the major fungus-like members of the stramenopiles. They are covered in Chapter 17 in your text. They are often referred to as fungi and mycological terminology is used to describe them. The oomycetes, like true fungi, excrete extracellular digestive enzymes into their surroundings and absorb the breakdown products of their substrates. This is known as lysotrophic nutrition (most organisms can do this trick, but fungi and "fungal" stramenopiles are the only eukaryotes that rely solely upon this form of heterotrophy). The oomycetes which we will examine all are filamentous and coenocytic. The individual filaments are called hyphae and the whole thallus is called the mycelium. Oomycetes can reproduce asexually and sexually. The diploid thalli reproduce asexually by means of biflagellated propagules called zoospores and sexually by the formation of gametangia called antheridia and oogonia. The male "gametes" are haploid nuclei produced in the antheridia. The female gametes are eggs produced by the oogonia. The products of fertilization, the zygotes, are called oospores, and they mature in the oogonia.

There are two major groups of the oomycetes, the Saprolegniales, commonly known as water molds, and the Peronosporales, many members of which cause important plant diseases, including root rots, potato blight, downy mildews, and white rust. We will concentrate on the Saprolegniales, but we may see some examples of the Peronosporales during the semester.

Saprolegniales. These "fungi" have large, coarse hyphae, large terminal zoosporangia which produce primary zoospores, and/or primary zoospore cysts, primary cysts then germinate as typical (aka, secondary) zoospores, and oogonia with more than one egg. Examine mycelia of oomycetes growing on sesame seeds in your water samples. Mount a seed in water in a small petri dish and place the dish on a slide. Under low power, look for and draw zoosporangia and zoospore release, if found. Also look for and draw oogonia with eggs and/or oospores and antheridia at the tips of antheridial branches. You should move some of your material to a slide so you can draw the material in detail. Arrange your drawings in life cycle order. (See the life cycle of Saprolegnia in your text.)

Common genera you are likely to find are: Saprolegnia* spp., Achlya spp, and Dictyuchus spp.

Peronosporales. These "fungi" may be encountered on your seeds or as pathogens we see on plants later in the semester. These organisms tend to have delicate hyphae, small zoosporangia which produce typical zoospores directly, and oogonia with only a single egg. Some can grow as saprophytes; others are obligate plant pathogens.

A common saprophytic genus you are likely to see is: Pythium sp. If you find this on your seeds, you may wish to draw it.

Common pathogens we may see on shepherd's purse, Capsella bursa-pastoris, later in the semester are: Peronospora parasitica, downy mildew, and Albugo candida, white rust. If we find these two species, we will draw them.


Stramenopiles III - The Brown Algae

The Phaeophyta, or brown algae are all multicellular and filamentous. The largest members form big, macroscopic seaweeds. Most species are marine or estuarine, with only an handful of species occurring in freshwater. These are the stramenopiles most analogous to land plants with respect to their life cycles and large, complex thalli. We will examine several examples of marine browns that illustrate the range of morphological types and life cycles found in this group.

Ectocarpus* sp. This delicate, filamentous brown alga grows on various solid substrates in marine and estuarine habitats. It exhibits an isomorphic alternation of generations. That is, the haploid somatic stage, the gametophyte, looks identical to the diploid somatic state, the sporophyte. These stages can be distinguished from each other only when they become reproductive. Examine and draw a habit of Ectocarpus sp. from a herbarium sheet, and from live material. From prepared slides, draw the reproductive structures, plurilocular gametangia, of the presumed gametophyte. From the same slides, draw the reproductive structures, the asexual plurilocular zoosporangia and the sexual unilocular zoosporangium, of the sporophyte. Why can you be sure you are drawing a sporophyte but not a gametophyte? In live material, draw a cell in which the plastids, pyrenoids, nucleus, and central vacuole are labeled. Also draw any reproductive structures that may be present. Identify which stage(s) of the life cycle might be present.

Kelps, Order Laminariales. The kelps have a heteromorphic alternation of generations. This means that the sporophyte and gametophyte differ in appearance. Like the vascular land plants, the sporophyte is the dominant (more obvious) generation while the gametophyte is small and inconsequential in appearance. We will concentrate only on the sporophytes of kelps. Examine and draw the habit of one of the specimens of Laminaria* spp. Make sure to label the leaf-like blade, stem-like stipe, and anchoring holdfast. (See the life cycle of a kelp in your text.)

Fucus* sp. Members of the order Fucales lack a gametophyte stage (therefore, there is, by convention, no sporophyte). The gametes are produced on the diploid thallus in gametangia in which meiosis occurs. Make your drawings from specimens, material from your kit, and from sections of receptacles on the prepared slides. Make a habit drawing of the thallus and label the holdfast, stipe, blade or frond, float (if present), and receptacles, the swollen, bumpy structures at the tips of some fronds. The bumps on the receptacles are the sites of reproductive organs, the conceptacles. Make a free hand section of a receptacle such that you section through several conceptacles. Make a detailed drawing of a conceptacle, and label the ostiole and the gametangia. Determine whether the thallus was monoecious (with oogonia and antheridia present) or dioecious (with only oogonia or antheridia present). Draw the gametangia in detail and label the parts. If you have monoecious thalli, be sure to find someone else who has material of the other sex or find the other sex on the prepared slides. If we have live material, you might see egg and sperm release. (See the life cycle of Fucus in your text.)


Simple Stramenopile Algae, Chrysophytes, Xanthophytes, and Diatoms: Checklist for Notebook

Chrysophytes

___o___ Ochromonas sp. Label __o___plastids, ___o__flagella, ___o__nucleus (if seen), __o___laminarin

___x__ Mallomonas sp. Label __x__plastids, __x__flagellum, __o__nucleus (if seen), __o___laminarin, __x__silica scales

___o__ Dinobryon sp. Label __o__colony, __o__cell, ___o_plastids, __o__eyespot, __o__flagella, __o__nucleus (if seen), ____laminarin, __o__lorica

__x___ Synura sp. Label __x__colony, __x__cell, ___x_plastids, __x__flagellum, __o__nucleus (if seen), __o__silica scales

Xanthophytes

___x__ Vaucheria sp. Label __x__filaments with branches and tips,__x___rhizoid, __x__plastids, __x__central vacuole, __o__zoosporangium (if seen), __x__antheridium, __x__oogonium with egg or zygote

Diatoms

Centric Diatoms

__x__ Stephanodiscus sp. Label ___x_ cell in valve view, ___o_cell in girdle view, __x__plastids, _x__nucleus, __x__oil drops, __x__valve, __o__girdle bands, __o__chitin fibers

Other centric diatoms you might see and draw

Melosira sp.

Pennate Diatoms

__o___ Navicula sp. Label __o__cell in valve view, ____cell in girdle view, __o__plastids, __o__nucleus, __o__oil drops, __o__valve, __o__raphe, ____girdle bands

Other pennate diatoms you might see and draw

Asterionella, Fragillaria, Tabellaria, Gomphonema, Cymbella


Plant Analogs among the Stramenopiles, the Brown Algae: Checklist for Notebook

Ectocarpus sp.

__x__ Habit, herbarium specimen, __x___ Habit, live specimen. Label __x__plastids, ___x_pyrenoid, __x__nucleus, __x__plurilocular structure, prepared slide Label _x___unilocular structure, ___x_diagram life cycle

Kelps, Laminaria sp.

__x___Habit, live specimen of sporophyte, Label __x__holdfast, ___x_stipe, ___x_blade. Prepared slide of blade, XS, Label __x__zoosporangium (a unilocular structure)

Fucus sp.

__x__Habit, live specimen, Label ___x_holdfast, __x__stipe, __x__blade, __o__float, __x__receptacle, __x__conceptacle, Prepared slide or freehand section of receptacle with conceptacles, Label __x__conceptacle, __x__ostiole, __x__sterile filaments, __x__oogonium, __x__eggs, __x__antheridium, ___x_sperm


Fungus Analogs Among the Stramenopiles, The Oomycetes: Checklist for Notebook

Saprolegniales

Saprolegnia sp. (We have also seen some Dictyuchus sp. and some Achlya sp.)

__x___Habit of mycelium live specimen on sesame seed, Label __x__hypha, __x__mycelium, __x__Detail of hypha and reproductive structures, Label __x__vacuole, __x__cytoplasm, __x__zoosporangium, ___o_zoospore release (if seen), __o__primary zoospore (if seen in Saprolegnia), __o___primary zoospore cyst (if seen), __o__primary zoospore cyst ball (if seen in Achlya), _____release of typical (aka secondary) zoospore from primary zoospore cyst (if seen in Achlya), ___x_antheridial branch, __x__antheridium, __x__fertilization tube, __x__oogonial initial, __x__oogonium in which eggs are cleaving, __x__mature oogonium with eggs and/or young oospores, __x__mature oogonium with mature oospores, Label __o__oospore wall, ___o_laminarin

Peronosporales

Pythium sp.

__o___Habit of mycelium, Label ___o__hypha, ___o__zoosporangium, _____zoospore release (if seen), _____typical zoospore (if seen), ___o__antheridium (if seen), ___o__oogonium with single egg or oospore (if seen)


Survey of the Plant Kingdom Laboratory

Exercise III - Miscellaneous Protist Algae, the Dinoflagellates, Euglenoids, and Cryptomonads

Various groups of protists (eukaryotes that are not FAP eukaryotes) have both photosynthetic and heterotrophic members. The photosynthetic members of these groups are usually treated as algae. Almost all members of these groups are motile unicells, although other morphological types are occasionally found. This exercise will cover a number of these microscopic protist algae. Remember, none of these groups is particularly closely related to the others. It is just convenient to study them together at this point. We may find some very good examples of these algae late in the semester. Be prepared to revisit them. These algae are covered in Chapter 16 of your text.

Pyrrhophyta - Dinoflagellates. This is a very large group of environmentally important protists whose closest relatives appear to be the ciliates and apicomplexans or sporozoans. The name alvelolates has been suggested for this group, and there is some suggestion that the alveolates may be a sister group to the stramenopiles. Some species of dinoflagellates are photosynthetic; others are not. Most species of dinoflagellates are encountered as motile, uninucleate unicells with two flagella. These are the forms of dinoflagellates we will observe. Because of the arrangement of the flagella, the cell spins around its anterior to posterior axis as it swims. One flagellum is coiled and located in a groove, the cingulum, which wraps around the middle of the cell. The action of this flagellum causes the cell to spin and swim forward. The second flagellum is straight and extends from a longitudinal groove, the sulcus, which is arranged at right angles and posterior to the cingulum. The second, trailing flagellum apparently acts as a rudder in most species. Some dinoflagellates are smooth in outline and appear naked. These are called naked or gymnodinoid dinoflagellates. Other dinoflagellates have a number of cellulosic plates in sacs, alveoli, just under the plasma membrane. The plates give the cell an armored appearance. Armored dinoflagellates are referred to as peridinioid. We are most likely to encounter examples of peridinioid dinoflagellates. The nucleus is usually visible as a clear region in the middle of the cell near the junction of the cingulum and sulcus. Plastids, when present, usually range from golden brown to olive green in color.

Find and draw at least one example of a dinoflagellate. Be sure to label the sulcus and cingulum, the flagella (if seen), the nucleus, the plastids, and the plates (if present). Examples: Ceratium sp., Peridinium* sp.

What dinoflagellate has been a big hit in the news in the last few years? What morphological forms does it exhibit?

Euglenophyta - Euglenoids. Most higher taxa of euglenoids have no photosynthetic species. However, the photosynthetic euglenoids are very well known and well studied. The euglenoids are a sister group to the kinetoplastid flagellates, a group of classical "protozoans" that includes the trypanosomes and the bodonids. This group, sometimes referred to as the euglenozoids, appears to have diverged very early in the history of the eukaryotes. The euglenoids we will study are all flagellated unicells with one or more plastids. All euglenoids have two or more flagella that arise from an invagination, the canal and reservoir, at the anterior end of the cell. In most of the species we will encounter, only one long flagellum emerges from the reservoir. An orange eyespot lies against the reservoir near the base of the flagella. Most euglenoids have somewhat elongated cells with a distinct helical symmetry. The cells have a definite shape but have no cell wall. The shape of the cell is maintained by a series of proteinaceous strips, the pellicle, which lie under the plasma membrane and describe a helical pattern from the anterior to posterior end of the cell. Some euglenoids are rigid, others are quite flexible, exhibiting euglenoid motion (aka, metaboly). One genus you may encounter, Trachelomonas, has an extracellular envelope, the lorica, which is often darkened by the presence iron compounds. The cell may contain one to many bright green plastids which may or may not have pyrenoids. Usually there numerous shiny food storage granules called paramylon bodies. The single nucleus is usually visible as a clear area in the central part of the cell.

Find and draw one or more examples of euglenoids. Be sure to label the flagellum(a) (if seen), canal, reservoir, eyespot, pellicle, nucleus, plastids, pyrenoids (if seen), and paramylon bodies. Examples: Euglena *sp., Phacus *sp., Trachelomonas sp. (We may also encounter the colorless euglenoid Peranema sp.)

Cryptophyta - Cryptomonads. We may encounter some very fast moving flagellated, unicells which are elongated and ovoid to almost rectangular in outline. They are typically laterally compressed. Some taxa are photosynthetic. These are cryptomonads. Two flagella arise from an invagination, the gullet, at the anterior end of the cell. The gullet is lined with rectangular bodies, ejectosomes. Plates, analogous to those of dinoflagellates are found under the plasma membrane. Photosynthetic members of the cryptomonads may show a broad range of colors. If we encounter good examples of cryptomonads, you will be given directions on what to label.


Miscellaneous Protist Algae: Dinoflagellates and Euglenoids: Checklist for Notebook

Dinoflagellates

Peridinium sp. __x___Habit, Label __x__cingulum, __x__sulcus, __o__nucleus (if seen), __o__plastids, ___o__girdle flagellum (if seen), __o__trailing flagellum (if seen), __x__plates

Euglenoids

Euglena sp. __x___Habit, Label ___o__flagellum (if seen), __x___canal and reservoir, __x___eyespot, ___o__contactile vacuole, __x___plastids, ___x__paramylon, __o___nucleus (if seen), __o___pellicle

Phacus sp. ____Habit, Label ____flagellum, ____canal and reservoir, ____eyespot, ____contractile vacuole, ____plastids, ____paramylon, ____nucleus, ____pellicle

Cryptomonads

Cryptomonas sp.___o___Habit, Label __o__flagella (2), __o__gullet, __o__ejectosomes, __o__nucleus, __o__plastid


Survey of the Plant Kingdom Laboratory

Exercise IV - Protists with No Place Else to Go - The Slime Molds

The slime molds are considered botanical organisms because they produce spore bearing structures that are superficially similar to the reproductive structures of some of the true fungi. They are members of the decomposer community in terrestrial habitats where they are predators of bacteria and eukaryotic microorganisms. A slime mold is an organism which has an amoeba as a trophic (= somatic, feeding, or vegetative) state and produces a spore bearing structure called a fruiting body. In some slime molds, such as the myxomycetes, a single amoeba develops into one to several fruiting bodies. Other slime molds, such as the dictyostelids, are called cellular slime molds because many amoebae aggregate together to make a multicellular fruiting body. Various unrelated groups of amoeboid protists have members that are slime molds. We will concentrate on examples of the two types of development mentioned above by looking at the myxomycetes and the dictyostelids. We will also examine the microscopic fruiting bodies of members of a group called protostelids. Slime molds are discussed in Chapter 16 of your text.

Myxomycetes*, the Plasmodial Slime Molds. The myxomycetes are the first group of slime molds which were recognized. Their spore bearing structures, fruiting bodies, vary from small, stalked sporangia to large amorphous masses called aethalia. Several examples of myxomycete fruiting bodies will be available for you to examine under dissecting microscopes. Make habit sketches of two or three examples. A slide will be set up on the teaching microscope for you to examine the microscopic structures of a stalked sporangium. Draw and label the stalk, peridium (if observable), columella (if present), spores, and capillitium.

Spores germinate to produce amoebae that are capable of producing flagella. The name I prefer for this type of cell is the amoeboflagellate. Other names for these cells include swarm cells (when flagellate), myxamoebae, and myxoflagellates. If we can get some fresh material, draw some amoeboflagellates. You should be able to see a long anterior flagellum, the nucleus, and the water expulsion vacuole.

Amoeboflagellates differentiate physiologically to become gametes. After the fusion of compatible gametes, the zygote develops into an amoeboid coenocyte called the plasmodium. In larger species of myxomycetes, the plasmodium forms a large reticulum of veins. The cytoplasm in the veins streams regularly backward and forward, shuttle streaming. Draw a habit of a plasmodium, and indicate how shuttle streaming occurs. The plasmodium eventually develops into one or more fruiting bodies.

If fertilization follows the fusion of two amoeboflagellates, where does meiosis occur?

(See the life cycle of a myxomycete in your text.)

Dictyostelid Cellular Slime Molds. Remember, the cellular slime molds make fruiting bodies as a result of the aggregation of many individual amoebae into a structure the eventually develops into a multicellular fruiting body. In the dictyostelids, the fruiting body consists of a stalk made of dead stalk cells and one or more masses of spores, the sorus(i). Sprinkle a pinch of forest soil perpendicular to a streak of E. coli on an agar plate. After 5-7 days, find and identify dictyostelid fruiting bodies. Draw them. Draw any other stages of the life cycle that might be present.

Protostelids. Protostelids are slime molds with simple, microscopic fruiting bodies, each of which typically has a single spore supported by a delicate, tubular stalk. The amoebae of protostelids are quite variable, but we will not be considering them here. Examine a piece of dead, decaying plant material under the light microscope, and draw the fruiting bodies of a protostelid. Label the spore and the stalk.


Mycetozoans: Checklist for Notebook

Myxomycetes

__x___ Habit of fruiting bodies of Stemonitis axifera, Label on each __x__sporangium, __x__capillitium, __x__spores, __x__stalk, __x__hypothallus

__x___Detail of fruiting body of Stemonitis axifera, Label __x__stalk, _x___spores, __x__capillitium, __x__columella

___x__Plasmodium of Didymium sp., Label __x__veins, __x__advancing feeding front

______Amoeboflagellates, Label _____cell body, _____nucleus, _____flagellum, _____contractile vacuole.

Dictyostelids (demonstration)

__x___Low power habit of fruiting body of Dictyostelium sp., Label __x__stalk, __x__sorus of spores

__x___Low power habit of population of amoebae, Label __x__amoeba

___x__Low power habit of aggregation, Label __x__aggregation center, __x__aggregation stream, __x__amoeba

__x___Low power habit of slug, Label __x__slug, _x__stalk

___x___Low power detail of fruiting body, Label __x___spore, ___x__cellular stalk.

Protostelids

_____Low power habit of fruiting body of at least one species, Label ____spore, ____stalk, ____apophysis of stalk (if present)


Survey of the Plant Kingdom Laboratory

Exercise V - The Fungi

There are, actually, few morphological characters which define the Fungi. The definitive characters are all chemical and molecular. All Fungi, like oomycetes, are lysotrophic (they excrete digestive enzymes and digest their food extracellularly, sort of like us if you think about it). Many of them are mycelial, though some are smaller and unicellular as we shall see. All cells, except the zoospores and flagellated gametes of Chytridiomycetes, have cell walls, and the vast majority of Fungi have chitin (or chitosan) as a component of the cell wall. The sequence of nucleotides in a number of different genes also unite the Fungi as a monophyletic group. Fungi are discussed in Chapter 15 of your text.

The Fungi I - Chytridiomycetes

These are the only Fungi that have flagellated cells, the zoospores and, in some cases gametes. All flagellated cells are wall-less and have posterior, pushing, whiplash flagella. Most have flagellated cells that are uniflagellate. During asexual production, a chytridiomycete thallus develops one or more zoosporangia whose contents cleave into numerous uninucleate zoospores. Zoospores are released, swim for some period of time, and then encyst. The cyst germinates to form a new thallus. Sexual reproduction varies from group to group in the Chytridiomycetes. We will look at one example. The thalli of chytridiomycetes vary from unicellular forms that produce a single zoosporangium, the monocentric chytrids, to mycelial forms. We will look at examples at each extreme of the morphological spectrum.

Monocentric Chytrids*. These fungi are members of a number of taxa within the chytridiomycetes. We will not try to identify any of these, rather we will focus on the morphological features they have in common. Therefore, just label your drawings: "Monocentric chytrids". Most monocentric fungi colonize small, often unicellular substrates such as a pollen grain or a single algal cell.

We have added pine pollen as bait into samples of water you brought in. To the naked eye the pollen looks like a white to pale yellow powder on the top of the water. Carefully touch a coverslip to a pollen covered area on a water sample. This will allow you to pick up a sample of pollen in a drop of water. The drop will hang from the bottom of your coverslip. Place this drop in a drop of distilled water on a slide. (We will demonstrate this.) Examine the slide under low power (10x) until you find a number of pollen grains. (Pine pollen looks like little Mickey Mouse heads.) Once you have found the pollen, switch to high dry power and look for the zoosporangia of chytrids extending from the surface of the pollen grains. The will look like little colorless spheres. Examine and draw some. Find and draw uncleaved zoosporangia and zoosporangia that have cleaved and contain zoospores. Draw zoospore release. Label the zoosporangium, cleaved zoospores, released zoospores (with flagella), and the structure through which the zoospores exit from the sporangium. Each zoosporangium is anchored in the pollen grains by an absorptive system, the rhizoids. Since the rhizoids are inside the pollen grain you may not see them. If you do, draw and label them. Also, look for monocentric chytrids on diatoms and other algae. In these chytrids it is often possible to see the rhizoids in the host cell. How do chytrids on algae compare to those on pine pollen?

Allomyces arbuscula*. The species in the soil-inhabiting genus Allomyces are mycelial. This fungus has an unusual life cycle in the Fungi because it has an alternation of generations, an isomorphic alternation of generations. That is, the gametophyte (= gametothallus) is morphologically identical to the sporophyte (=sporothallus). Both consist of thick, coenocytic, dichotomously branching hyphae that are anchored to the substrate with thinner hyphae called rhizoids. Find and draw the habit of a mycelium growing on a sesame seed.

When mycelia become reproductive, it becomes possible to distinguish the gametophytes from the sporophytes. To the naked eye, the reproductive gametophytes are orange and the reproductive sporophytes are brown. As we will see, at the microscopic level the reason for this color difference becomes apparent. Pairs of gametangia are found at the tips of the branches of gametophytes, a terminal, colorless female gametangium, and a subterminal, orange male gametangium. When flooded with fresh water, the gametangial contents cleave up into gametes, and the gametes are released from the gametangia. Allomyces is anisogamous. Both sexes of gametes are flagellated, but the males are small and fast swimming while the females are large and slow. Females release a pheromone that attracts males. The males cluster around the females, then pairs of fusing gametes swim off and form zygotes. Zygotes can be distinguished because they have two flagella. The zygotes encyst, then germinate as sporophytes. The sporophytes produce sporangia of two types. The colorless sporangia are zoosporangia that cleave and release diploid zoospores. The zoospores encyst and germinate as sporophytes. The brown sporangia with pitted walls are resting sporangia (=meiosporangia). After a period of dormancy and drying, the resting sporangia undergo meiosis, cleave up, and release haploid zoospores. The haploid zoospores encyst and germinate as gametophytes.

Remove some mycelium of A. arbuscula from a sesame seed and place it into some distilled water on a slide. Do not place a coverslip on this sample. Most samples will contain both gametophytes and sporophytes. Examine the mycelia under 10x, and find and make habit sketches of gametophyte hyphae with female and male gametangia. Also, find and make habit sketches of sporophyte hyphae with zoosporangia and resting sporangia. As gametangia and zoosporangia begin to release their contents, place a cover slip on the slide and draw gamete release and fertilization and zoospore release. Also, draw zygotes with recognizable features if you can. Finally, find a sporophyte and draw a zoosporangium and a resting sporangium in detail. Why do you not see resting sporangia releasing their contents?

(See the life cycle of Allomyces in your text.)


The Fungi II - Zygomycetes.

The zygomycetes are defined by the production of sexual spores called zygospores. There are a number of subgroups of fungi in the Zygomycetes. We will concentrate on examples from the order Mucorales. All members of the Mucorales are mycelial, usually with nonseptate somatic hyphae. When they reproduce asexually, the contents of a specialized terminal cell, the sporangium, cleave up and differentiate into walled spores, sporangiospores. In many of the Mucorales, there are large numbers of spores produced in a sporangium, while in others each sporangium, now referred to as a sporangiolum, produces only from one to a few spores. When spores are carried to a suitable substrate, they swell and then extend a hypha, the germ tube, which develops into a new mycelium. When members of the Mucorales become sexual, compatible hyphal tips are attracted to grow toward each other. When these specialized hyphal tips come into contact, they begin to swell. At this stage these structures are called progametangia. As the progametangia continue to develop, cytoplasm concentrates at their tips and is cleaved off to produce coenocytic cells called gametangia. The basal part of each former progametangium is now referred to as the suspensor. Next, the two gametangia fuse and develop into a thick-walled zygospore (aka, zygosporangium). The zygospore is supported by the two suspensors. After a period of dormancy, the zygospore will germinate. Between the formation of the zygospore and its germination, compatible nuclei from each gametangium will pair up, fuse to form zygote nuclei, and the zygote nuclei will undergo meiosis. The zygote nuclei are the only diploid states in the life cycle.

We will examine the asexual and sexual reproductive structures of several members of the Mucorales. We will not observe zygospore germination.

Asexual Reproduction*. Place some soil and litter on an agar plate and wait several days. Numerous mucoralean fungi will sporulate in this time. Scan the closed plate with the 4x objective and locate sporulating mycelia of zygomycetes. Do not open the plate until it has been declared free of Rhizopus. Find at least two examples of mucoralean fungi on your plate and make habit sketches of the sporangiophore (the hypha that supports the sporangia and/or sporangiola) and the sporangia and/or sporangiola. We will help you to identify each fungus. Mount some sporangia and/or sporangiola on a slide and draw the internal structures under the 40x objective. You should see the spores and perhaps a columella and the sporangium wall. Common soil genera around here include: Mucor, Zygorhynchus, Absidia, Choanephora, Cunninghamella, and Rhizopus. If you scan your plate and find Rhizopus, do not open it.

An interesting member of the Mucorales is the genus Pilobolus* which grows and sporulates on herbivore dung. Spores are eaten along with plants by herbivores. They pass through the animal's digestive tract and grow on the undigested plant material in the freshly deposited dung. When the fungus sporulates it must get its spores to the surrounding vegetation. It does this by actively shooting its whole sporangium off from the tip of the sporangiophore. When the sporangium hits a leaf, the mucilaginous matrix around the spores causes it to stick. Examine a bolus of dung with Pilobolus growing on it. Draw and label a sporangiophore and sporangium. What characteristics of this structure are associated with successfully shooting the sporangia off the dung?

Sexual Reproduction*. We are unlikely to find examples of zygospores in our collections. Therefore, take a prepared slide of Rhizopus stolonifer* which shows zygosporogenesis and find and draw progametangia, gametangia and suspensors, young zygospores and suspensors, and mature zygospores and suspensors. Hint: it is often easiest to work backward from the mature zygospores to the suspensor.

(See the life cycle of Rhizopus stolonifer in your text.)


Fungi III - Ascomycetes

The Ascomycetes are the most species rich group of fungi, with estimates that there may be in excess of one million species. Needless to say, we will not have time to sample too many of them. However, it is fairly easy to learn the basics. Most ascomycetes are mycelial with septate hyphae. Some are able to grow as yeasts. All produce spores that are the products of meiosis in a sac-like structure called the ascus. We will examine both filamentous and yeast forms of ascomycetes.

Filamentous Ascomycetes.

Filamentous ascomycetes have extensive haploid mycelia as their primary somatic state. When filamentous ascomycetes reproduce asexually, they typically produce spores externally on the hyphae. These spores are called conidia (conidium, sing.). There is a great diversity of conidial morphologies and conidial development among the ascomycetes. As a result, many species, when they are forming only conidia, are given a taxonomic name for the conidial state. This name is different from the name of the sexual state. This is a level of confusion that ascomycete experts are willing to suffer. We will examine a few of the more common types of conidial states that are found around here. When filamentous ascomycetes are sexual, they produce a cell inside of which karyogamy, meiosis, and spore development occur. This structure is the ascus(i), and the spores that develop in it are the ascospores. Asci in the vast majority of filamentous ascomycetes are surrounded by sterile tissue with a distinctive morphology. This combination of sterile tissue and asci is called an ascocarp, or, simply, a fruiting body. We will examine a few examples of fruiting ascomycetes that develop on herbivore dung. Although there are usually sex organs that precede development of the fruiting bodies and asci, we will not observe them in lab. Remember, although we will be observing reproductive structures, that the bulk of each fungus is made of somatic mycelium.

Asexual Reproduction*. A number of the common molds are conidial states of ascomycetes. They can be found by placing pieces of dead plant material on agar plates and allowing the fungi on them to grow out. Find and identify one example of a conidial fungus growing on or around dead plant parts. Draw and label the conidia and the cells that produce them, the conidiogenous cells. Also, the conidiogenous cell(s) may be supported by a specialized hypha, the conidiophore. If the fungus you examine has a conidiophore, draw and label it. Common genera of conidial fungi around here are: Aspergillus, Penicillium, Cladosporium, Fusarium, and Alternaria.

Sexual Reproduction*. There are a number of types of fruiting bodies produced by filamentous ascomycetes. We will focus on two major types produced by common species of ascomycetes that grow on herbivore dung. Open, disc-shaped ascocarps are called apothecia (apothecium, sing.). They have a platform of sterile tissue which supports an exposed layer of asci. Bottle or flask-shaped fruiting bodies that have a small opening at the top are called perithecia (perithecium, sing.). They have sterile tissue that almost completely surrounds a layer of asci.

Examine and draw an example of an apothecial fungus and a perithecial fungus. Mount each fruiting body very gently under a coverslip such that you do not distort it excessively. Make a habit drawing. On the apothecial fungus identify the sterile tissue and the hymenium, the layer of asci. On the perithecial fungus identify the broad venter, the narrow neck, and the ostiole, or pore, at the top of the neck. If the perithecium is translucent, you may be able to see the silhouette of the hymenium through the venter. Squash each fruiting body such that the asci spread out free of the sterile tissue. Draw and label young asci which consist of a single cell, maturing asci in which the ascospores are cleaving inside the surrounding cytoplasm, and mature asci with mature ascospores.

Lichens*. Roughly half the described species of ascomycetes are lichens. Lichens, as first recognized by Beatrix Potter, are symbioses between a fungus, usually an ascomycete, and one or more algae, usually green algae and/or cyanobacteria. Lichens are found in three basic growth forms: crust-like or crustose, leaf-like or foliose, and shrub-like or fruticose. Make a habit drawing of one of these types of lichen. Identify the growth form and any apothecia you might see. Make a section through an apothecium and draw. Identify which tissue is fungal, which contains algae, and the hymenium of the apothecium with its asci.

Yeasts. Yeasts are unicellular forms of ascomycetes and basidiomycetes. Perhaps the best known eukaryote is baker's yeast, Saccharomyces cerevisiae*. Examine living cultures of S.cerevisiae, and draw budding cells. Examine and draw asci of this yeast from prepared slides or live material. How is this ascus like those of filamentous ascomycetes? How is it different?


Fungi IV - Basidiomycetes

The Basidiomycetes are the group that contains the archetypal fungi, the Agaricales, or mushroom forming fungi. When most people think of a fungus, a mushroom comes to mind. Along with the mushroom fungi, the Basidiomycetes also contain the bracket and coral fungi, the jelly fungi, the rust fungi, and the smut fungi. Most basidiomycetes are filamentous with septate hyphae. Some are yeast-like for part or all of their life cycle. All basidiomycetes produce basidiospores on extensions of the cell, the basidium, in which karyogamy and meiosis occur. We will look at an example of a mushroom forming fungus and a rust or two.

Agaricales, the Mushroom Fungi*.

The agarics have relatively extensive mycelia that grow through the substrates. Their major somatic mycelia, the dikaryons, develop after the plasmogamy stage of fertilization, but karyogamy is delayed until the basidia form in the mushroom. The gills of the mushroom are the site of basidium formation with the basidia forming a layer, the hymenium, on the outer surface of the gill. Karyogamy and meiosis occur in the young basidia. After meiosis, the basidia expand and extend two to four horn like structures, the sterigmata (sterigma, sing.), beyond the outer surface of the gill. Basidiospores form at the tips of the sterigmata, and at maturity are shot into the space between the gills. Examine and make a habit drawing of one of the mushrooms available in class. Label the cap, stipe, and gills. Make a thin, tangential section of the cap that includes the gills. Lay the section on a dry microscope slide. We will demonstrate this. Look for and draw basidia with basidiospores. Label the basidium, sterigmata, and basidiospores.

Uredinales, the Rust Fungi.

The rusts are all plant pathogens. Most have a relatively complex life cycle. Look at the life cycle of wheat rust, Puccinia graminis, in your text book to see how complex a life cycle can be. You will notice that there are a number of different spore bearing states. We will look at a couple of rusts which illustrate some of those spore bearing states quite well. Do not worry about their life cycles. Match the states you see with the life cycle of P. graminis.

The basidium and basidiospores. The basidium of rusts is called a teliospore when it is young. At maturity, it develops into a 4-celled structure that produces basidiospores on sterigmata. Gymnosporangium* spp., the cause of cedar/apple rust makes telia which contain teliospores that mature quickly into basidia. Telia, the sites of teliospore formation develop on galls on junipers, Juniperus sp. Each telium produces a long, slimy, orange horn in wet weather in the spring. Make a habit sketch of a telial gall with horns. Squash a horn on a slide and find and draw teliospores and basidia with basidiospores. How is the basidium like that of a mushroom? How is it different?

The spermagonia and aecia. Basidiospores give rise to a haploid mycelium which produces sex organs, the spermagonia (spermagonium, sing.), on the host. The spermagonia produce male gametes, the spermatia, and female structures, the receptive hyphae. After plasmogamy, a dikaryotic mycelium develops in the host. This mycelium produces bell shaped sporulating structures called aecia (aecium, sing.). The aecia produce chains of dikaryotic spores called aeciospores. Spring beauty, Claytonia virginica, is often infected with the rust fungus, Puccinia marie-wilsoniae*. Make a habit sketch of an infected plant and indicate the aecia. Make cross sections of an infected plant and draw the spermagonia and the aecia. Make a detail sketch of the aeciospores.

Which spore state that is present in P. graminis did we fail to see?


Fungi I: Chytridiomycetes: Checklist for Notebook

Monocentric chytrids

__x___Habit of chytrids on pine pollen at 40x, Label __x__zoosporangium, __o__rhizoids (if seen), __o__immature zoosporangia, __x__mature zoosporangia with cleaved zoospores, __x__zoospore release, __o__zoospore with lipid droplet and flagellum (if flagellum seen)

Allomyces arbuscula

__o___Habit of mycelium on sesame seed

__x___Habit and details of gametophyte with gametangia at 10x and 40x, Label __x__hypha, __x__terminal female gametangium, __o__female gamete release, ___x_subterminal male gametangium, _o___male gamete release,__o__male or female gamete structure including flagellum __o__gamete clustering, ___o_gamete fusion, _o___zygote

__x___Habit and details of sporophyte with sporangia at 10x and 40x, Label __x__hypha, __x_resting sporangium, __x__zoosporangium, ____zoospore release, ____zoospore structure


Fungi II: Zygomycetes, Mucorales: Checklist for Notebook

Phycomyces blakesleeanus, living material

_____Habit of mated mycelia with the unaided eye, Label ____sporangiophores, ____region of zygospores

______Details of asexual reproductive structures at 10x and 40x, Label _____sporangiophore, _____columella, _____sporangium, _____spores

_____Details of sexual reproductive structures at high power of the dissecting microscope, Label ____zygophores, ____progametangia, ____gametangia, ____suspensors with appendages, ____young zygospore, ____mature zygospore

Rhizopus stolonifer, preserved or prepared slides

__x___Sporangia and sporangiophores from kit at 10x and 40x, Label __x__stolon, __x__rhizoids, ___x_sporangiophore, _x___columella, __x__sporangium, __x__spores

___x__Zygospores and zygosporogenesis from prepared slides at 40x, Label __o__progametangia (if seen), ___x_gametangia, __x__suspensors, __x__young zygospore, ___x_mature zygospore

Pilobolus sp., living material from dung (morning lab)

__x__Habit of sporangia and sporangiophores on dung, Label __x__sporangium, __x__subsporangial swelling, _x___sporangiophore, ___o_dispersed (shot) sporangia

__x___Detail of sporangium and sporangiophore at 10x and 40x, Label __x__sporangium, __x__sporangium wall, _x___spores, ___o__columella, __o__zone of dehiscence, __x__subsporangial swelling, __x__sporangiophore, __o__trophocyst


Fungi III: Ascomycetes: Checklist for Notebook

Filamentous ascomycetes, asexual reproduction

_____Ascomycete anamorph of Alternaria sp. and Fusarium sp., habit of conidia and conidiophores (demo) objective, Label __x__conidiophore,__x__ conidiogenous cell, __x__conidium

Filamentous ascomycetes, sexual reproduction

An ascomycete with an apothecium

__x__Apothecium of Ascobolus immersus or Iodophanus carnea, habit, Label __x__sterile wall of apothecium, __x__hymenium, __x__asci

__x__Detail of section with 10x and 40x objectives, Label __x__sterile tissue of apothecium wall, ____region of ascogenous hyphae, __x__hymenium with __x__paraphyses and __x__asci, including __o__zygote ascus (if seen), __o__developing ascus, and __x__mature ascus with __x__ascospores

An ascomycete with a perithecium

__x___Podospora sp.habit, Label __x__neck of perithecium, __x__venter of perithecium, __o__shed ascospores, __x__silhouette (see, I looked it up!) of asci including __o__elongating ascus

___x__Detail of crushed perithecium, Label __x__ascus including __x__developing ascus and __x__mature ascus with __x__ascospores and __x__ascospore appendages

A lichen, Parmelia sp.

___x__Habit, identify whether it is crustose, foliose, or fruticose, Label _x___somatic thallus, ___x_apothecium

___x___Section of thallus including apothecium, Label __x__outer fungal layer, __x__algal and fungal layer, __x__inner fungal layer (if present), __x__apothecium with _x___asci and __x__ascospores

A yeast

___x__Saccharomyces cerevisiae habit, Label __x__somatic cell, __x__bud, ____ascus (if present)


Fungi IV: Basidiomycetes: Checklist for Notebook

Mushroom forming basidiomycetes, Agarics

__x___Habit of mushroom, either Agaricus brunnescens or Lentinus edodes, Label __x__stipe, __x__partial veil/annulus (if present), __x__cap, __x__gills

__x___Longitudinal section of mushroom, Label all of above and __x__the way the gills are associated with the stipe

___x__Tangential section of cap including gills (try to observe with 40x objective for details), Label __x__gill, __x__hymenium, ___x_ apex of basidium with __x__two or four basidiospores on the tips of __x__sterigmata, __o__stages of basidiospore development

__x___Squashed preparation of gill on wet mount observed with 40x objective, Label __o__basidium with sterigmata, __x__free basidiospores

Rusts (to be done later)


Survey of the Plant Kingdom Laboratory

Exercise VI - Multicellular Protist Algae, the Red Algae

Rhodophyta - the Red Algae. The reds are primarily marine algae that lack any flagellated stage in the life cycle. Their plastids are very similar to cyanobacteria in pigments and structure. The group includes several thousand species that range from unicells to large seaweeds, some of which are economically important. They are among the most beautiful of all "plants". They are covered in Chapter 14 of your text. The cells of reds contain one to several nuclei and one to several plastids. The cells have distinct cell walls. The cells of most multicellular reds are attached to each other via unique structures called pit connections. Most red algae, those of the class Florideophyceae, have a relatively complicated life cycle with an alternation of generations with two distinct somatic diploid stages, the dependent carposporophyte and the free-living tetrasporophyte, and a somatic haploid stage, the gametophyte. Many species have separate male and female gametophytes. Examine and draw some of the herbarium specimens of red seaweeds.

Polysiphonia* spp. We will use the common filamentous red, Polysiphonia, as our example to study in detail. This genus has an isomorphic alternation of generations; therefore, the free living, somatic thalli of each generation look a lot alike. Examine and draw the habit of the thallus from herbarium specimens and from living material. Examine and draw the vegetative thallus of living Polysiphonia. Be sure to label the axial and pericentral cells, the apical cell of a branch, pit connections, and plastids.

The gametophytes of this alga are free living. The males produce branches with thousands of unicellular gametangia, spermatangia, that each release a single nonmotile gamete, the spermatium. The female gametophytes produce eggs,carpogonia, at the ends of specialized branches, carpogonial branches. Carpogonial branches are surrounded by a basket of cells, the pericarp. The pericarp and carpogonial branch form the young cystocarp. A long extension of the carpogonium, the trichogyne, extends from the cystocarp into the surrounding water where it might contact a spermatium. Upon fertilization, a number of events occur that lead to the production of a dependent, diploid coenocyte, the carposporophyte, that develops in the base of the cystocarp which has become much larger. Buds of the carposporophyte, carpsporangia, release large diploid cells, carpospores, that escape into the surrounding water. Carpospores germinate to form free living sporophytes, tetrasporophytes, which eventually develop sporangia, called tetrasporangia, in which meiosis occurs and four tetraspores are produced. Tetraspores are released and germinate to form male or female gametophytes. Examine living female gametophytes and prepared slides of Polysiphonia sp. to see the reproductive stages of this red alga. On the male gametophytes, draw and label the spermatangial branches and spermatangia. On the female gametophyte, draw and label the young cystocarps with extending trichogynes (live material) and the mature cystocarps with dependent carposporophytes and carposporangia. On the tetrasporophyte, draw and label the tetrasporangia and tetraspores. (See the life cycle of Polysiphonia in your text.) Also, examine living material of gametophytes of Callithamnion sp. to see if you can recognize the spermatangial branches, carpogonial branches, carposporophytes, and carposporangia.

Local Red Algae - Lemanea sp. and Batrachospermum sp. A few reds grow in fresh water. Locally, two genera are not uncommon in fast moving, cool water. Lemanea thalli look like bunches of knobby, dark brown bananas. Batrachospermum thalli look like red or bluegreen branched strings of beads or toad eggs. If we encounter these algae, you may be asked to draw them.

Some Reds Are Yummy. The marine genus Porphyra grows as thin blades, and is delicious. It is commonly known as nori and used for wrapping sushi in Japanese dishes. We will try to serve you some before the semester is out.


Red Algae: Checklist for Notebook

Florideophyte red algae

_x__Habits of red algae on herbarium sheet to include Polysiphonia sp. and other growth forms

__x___ Habits of living Polysiphonia sp., ____x_Callithamnion sp., _____Lemanea sp., and _____ Batrachospermum sp.

Polysiphonia sp.

__x__Detail of somatic filament of living and/or prepared specimens, Label __x__apical cell, __x__development of axial and pericentral cells, __x__primary and/or secondary pit connection, __x__plastids

___x__Female gametophyte, living, Label __x__young cystocarp, __x__trichogyne

___x__Female gametophyte, prepared slide, Label __x__mature cystocarp, __x__pericarp, __x__carposporophyte, ___x_carposporangium, __x__carpospore

__x___Male gametophyte, prepared slide, Label _x___spermatangial branch, __x__spermatangium

___x__Tetrasporophyte, prepared slide, Label __o__premeiotic tetrasporangium (if seen), __o__developing postmeiotic tetrasporangium, __x__mature tetrasporangium, __x__tetraspore


Survey of the Plant Kingdom Laboratory

Exercise VII - Shall we start the Plantae here? Chlorophyta, the Green Algae

The Green Algae and the Embryophyta, or Land Plants, are clearly a monophyletic group. All have similar chloroplasts, mitochondria, and transition structures in their flagella (when flagella are present). In addition, many metabolic pathways are similar, as are the sequences of a number of genes. It is a matter of taxonomic taste whether we wish to include them in a formal taxon, Plantae, or save that taxon for the Land Plants. There are, as we discussed in lecture, three major lineages within the greens, the Chlorophyceae (CL), the Ulvophyceae (U), and the Charophyceae (CA). The Land Plants are a monophyletic branch within the Charophyceae. We will beg the taxonomic questions in lab and cover the morphology of the greens. However, the group to which each example we cover belongs will be indicated for your information with the abbreviations above. Your text treats the Green Algae as protists in Chapter 14.

Somatic Morphology of Greens

The green algae are found in both freshwater and marine habitats and also in soil, on rocks and tree bark. We will concentrate on the various growth forms of the green algae in this lab. For each example you draw, indicate the morphology type with a labelled habit drawing. Include, where appropriate, all cell types, zoosporangia, and gametangia. Draw one somatic cell in detail, labelling the following when relevant: Cell wall, chloroplasts, pyrenoids, nucleus(i) (if seen), central vacuole, flagella (if seen), starch grains, and eyespots (if seen).

Flagellated Unicells*. These are unicellular algae that have each cell motile by means of two or more flagella. The most common such alga is Chlamydomonas* spp (CL). You may see this in some collections of flooded soil. It will also be available in culture.

Nonflagellated Unicells*. These unicellular forms are sedentary or move by gliding. There are numerous such species. The most easy to recognize are the unicellular desmids* (CA) which consist of cells with two mirror image halves. Find and draw a desmid. The taxon you find will be identified for you.

Flagellate Colonies*. These colonies consist of many similar looking flagellated cells, each of which looks similar to Chlamydomonas. In some colonial forms, there may be a division of labor such that most cells are vegetative and a few are reproductive. Volvox spp. have such an organization. Draw Volvox* sp. (CL) and show the different stages of daughter colony development.

Nonflagellated Colonies*. These colonies consist entirely of nonflagellated cells, all of which are similar. Some examples you are likely to see include: Hydrodictyon sp.(CL), Tetraspora spp. (CL), Scenedesmus spp. (CL), and Pediastrum spp. (CL). Draw one example of a nonflagellated colonial green alga.

Unbranched Filaments*. These algae have filaments that have a single file of cells. Some cells may be specialized for reproduction or all may be equally capable of reproduction. A holdfast may be present. Common genera with this growth habit include: Spirogyra* spp. (CA) and Oedogonium* spp (CL). Find and draw these algae.

Branched Filaments*. These algae have occasional true branches. Some cells may be specialized on them. Common genera include: Bulbochaete sp. (CL), Draparnaldia sp. (CL), Cladophora sp. (U), and Stigeoclonium sp (CL). Draw one species with branched filaments. If zoosporangia and zoospores are present, draw them.

Parenchymatous Growth*. A genus closely related to land plants that grows as an epiphyte on other algae and submerged plants is Coleochaete spp. (CA). It looks like a shield with long hairs. If you find some of this alga, draw it.

Blade-like Growth*. The marine alga Ulva lactuca *(U) has a flattened thallus, two cells thick and grows in large sheets. Examine and draw a habit of U. lactuca from a herbarium specimen. A cross section of U. lactuca will be available on a prepared slide.

Siphonous Growth*. Many members of the Ulvophyceae are large and unicellular. Some are multinucleate and others are uninucleate for most of their life history. Examine and draw the habit of Acetabularia sp., a marine species with a single, uninucleate cell. Show the holdfast, stalk and cap with its rays which contain cysts at maturity.

Chara* sp. (CA). This plant-like alga has distinct nodes and internodes with whorls of branches at the nodes. Make a habit sketch of this alga or its near relative, Nitella sp.from the demonstration dissecting microscope. Chara is closely related to the Land Plants.

Sexual Reproduction in Greens

The Chlorophyceae and Charophyceae are all haploid in the somatic state with the zygote being the only diploid state. Meiosis, therefore, is zygotic. The Ulvophyceae may either show alternation of generations or be strictly diploid in the somatic state. We will examine sex, if encountered, only in the first two groups. Isogamy, anisogamy, and oogamy are found among the greens. We will see examples of oogamy most frequently. This is because zygotes of oogamous species tend to remain in the oogonia.

Chlamydomonas reinhardtii. This species is heterothallic and isogamous. That is, only gametes of opposite mating type can fertilize each other, but the gametes are morphologically similar. Shortly after appropriately treated cultures of each mating type are mixed, the gametes will cluster together then pair up. The paired gametes will fuse to form a zygote. The zygote will secrete a thick wall and become dormant. After a period of dormancy, the zygote will undergo meiosis (and a round of mitosis) and release haploid somatic cells. Draw and label gametes and the early stages of fertilization. Draw and label mature zygotes. If available, draw and label postmeiotic zygotes. What about the life cycle of this organism makes it a useful genetic system?

Volvox sp. This genus is oogamous. Eggs develop in oogonia on female (or bisexual) colonies which consist of vegetative cells and oogonia. Sperm develop when some or all the cells of a male (or bisexual) colony cleave and differentiate into sperm packets. The sperm packets swim to a female colony and penetrate to the interior of the colony. At this point the sperm packets separate into individual sperm, and the sperm swim to the oogonia and fertilize the eggs. The zygotes then develop thick, spiny walls. If we encounter sexually reproducing Volvox, draw and label a female colony with eggs and zygotes, male colonies with sperm packets, and any stages of fertilization you are able to find.

Oedogonium sp. This filamentous green is oogamous. The oogonia are swollen intercalary cells on a filament and each contains a single egg or a zygote. Depending on the species, antheridia are small intercalary cells on the filament or form on small male thalli that develop near an oogonium. Find, draw, and label a filament of Oedogonium sp. with an oogonium*. If you find them, draw and label antheridia. You may find an identical system of oogamy in the genus Bulbochaete.

Spirogyra* sp. This genus is oogamous with an egg and an amoeboid male gamete. Compatible filaments conjugate such that adjacent compatible cells extend conjugation tubes toward each other. The tubes fuse and the male gamete migrates through the tube and fertilizes the egg. The egg then develops into a thick walled zygote within the cell wall of the egg producing cell. Find and draw conjugation. Label the conjugation tubes, gametes, and zygotes. If we do not find living material, there will be prepared slides available. You may also see conjugation in the related genus Zygnema. or in some desmids. However, these algae might best be considered isogamous, why?

Chara sp. This large alga produces multicellular oogonia and antheridia. Usually the gametangia are in pairs. The antheridia are complex, ball shaped structures that produce chains of spermatogenous cells. The oogonia consist of jacket of sterile cells surrounding a single egg. Upon fertilization, the zygote develops a thick, black wall inside the oogonium. If encountered, find and draw pairs of gametangia. Label the antheridium, oogonium and egg. Crush an antheridium and draw the chains of spermatogenous cells. Find and draw a mature zygote in an oogonium. How are the gametes and gametangia similar to those of Land Plants? How are they different?


Green Algae: Checklist for Notebook

Flagellated Unicells, Chlamydomonas reinhardtii

__x___Habit of somatic cell, Label __x__flagella, __x__chloroplast, ___x_pyrenoid, ___x_nucleus, __o__eyespot

_____Mating, Label ____cluster of isogametes, ____pairing isogametes, ____tetraflagellate zygote, ____mature thick walled zygote

Nonflagellate Unicells, Desmids, e.g. Closterium sp., Cosmarium sp., Staurastrum sp., Micrasterias sp., Euastrum sp.

__x___Habit of somatic cell, Label, __x__semicells, __x__nucleus, __x__chloroplasts, __x__pyrenoids

_____Mating in Cosmarium sp., Label, ____walls of conjugated gametes, ____zygote

Flagellated Colonies, Volvox sp. (and/or Gonium sp., Pandorina sp.,Eudorina sp.)

__x___Habit of colony, Label __x__common sheath of colony, __x__flagellated somatic cells, __x__reproductive cells (gonidia) or daughter colonies, __o__inverting daughter colonies

_x___Details of somatic cell, __x__flagella, ___o_eyespot, __x__chloroplast, __o__cytoplasmic strands to adjacent cells

Nonflagellated Colonies, Scenedesmus sp., Pediastrum sp., or other

__x(pm)_Habit of colony, Label _x(pm)_ somatic cell with _x(pm)_chloroplast, __x(pm)_pyrenoid

Unbranched Filaments, Spirogyra sp. and Oedogonium sp., also Ulothrix sp., or other

___x__Habit of filament, Label __o__nucleus, __x__chloroplast, __x__pyrenoids; in Oedogonium sp. __x__annular scars, __x__holdfast

__x___Conjugation in Spirogyra sp. or Zygnema sp., Label __x__cojugation tubes, __x__gametes, __x__zygotes

___x__Sexual reproduction in Oedogonium sp., Label __x__oogonium with egg and/or oogonium with zygote, ____miniature male filament with ____antheridia, ____androsporangia (the small zoosporangia from which the miniature male zoospores were released)

Branched Filaments, Bulbochaete sp, Cladophora sp., Stigeoclonium sp., Draparnaldia sp., or other.

___x__Habit of thallus, Label ___x_somatic cell with __x__chloroplast, _o___nucleus, __x__in Bulbochaete, hair cell with bulbous base

__o___Sexual reproduction in Bulbochaete sp. Label __o__oogonium with egg, __o__oogonium with zygote, ____miniature male filament with ____antheridia

Bladelike Thallus, Ulva lactuca

__x___Habit of thallus from herbarium sheet

Siphonous Thallus, Acetabularia sp.

_____Habit of thallus, Label ____holdfast, _____stalk, ____cap with rays

Chara sp. or Nitella sp.

__x___ Habit of thallus, Label __x__internodes, __x__whorls of branches ("leaves"), ____antheridium, ____oogonium

___x__Details, Label __x__plastids in cell, ____gametangia showing ____jacket of antheridium, ____jacket of oogonium, ____egg (or zygote)


Survey of the Plant Kingdom Laboratory

Exercise VIII - Now we're sure we have Plantae. The Land Plants or Embryophytes

Embryophytes I - The Life Cycle

From this point on, you need to worry about only one life cycle. The stages are the same in all plants, but the details of morphology will vary from group to group. The Land Plants are a branch of the charophyte lineage of Green Algae. All Land Plants have a heteromorphic alternation of generations. All are oogamous with egg and sperm as gametes. All have an egg that remains in the gametophyte through fertilization. All have a zygote that germinates in the gametophyte (or a modification of the gametophyte in angiosperms) to become an embryo, the earliest stage of sporophyte development. All have the embryo develop into a mature sporophyte which produces spores in at least one sporangium. All have spores that germinate and develop into gametophytes. All (except the angiosperms and some gnetophytes) produce an egg in a specialized oogonium called the archegonium. All (except the seed plants) produce sperm in an antheridium. As an example of thex Land Plant life cycle we will look at ferns because all the stages of the life cycle are relatively easy to observe. Land Plants are discussed in Chapters 18-22 of your text.

Ferns - The Pteridophyta. The ferns are vascular plants (their sporophytes contain xylem and phloem) with a free living, macroscopic gametophyte and a macroscopic sporophyte that is free living at maturity. Like all vascular plants, the sporophyte is the dominant generation, meaning it is the most obvious manifestation of these plants. We will begin our tour of the fern life cycle with the mature sporophyte and follow the life cycle through to the next mature sporophyte generation. A fern life cycle is illustrated in Chapter 16 of your text.

The Fern Sporophyte*. We will focus on the most familiar group of ferns known as the leptosporangiate ferns in the order Filicales (don't worry about these names), i.e., the ferns that produce patches of small, stalked sporangia on the lower surfaces of their sporophylls (sporangium-bearing leaves).

Ferns, like almost all vascular plants, have sporophytes with true roots, stems, and leaves as their major somatic organs. These organs all contain strands of xylem and phloem. The strands of these vascular tissues are called the stele in roots and stems and veins in leaves. All the aerial parts of the sporophytes are covered with a waxy layer, the cuticle, on the outer surface of the epidermis. Stomata (stoma, sing.) that open and close are found as part of the epidermis on leaves and stems. New stems and leaves on a sporophyte develop from outgrowths at the surface of the shoot apical meristems. New roots develop from new meristematic regions buried inside other roots or stems.

Several different species of ferns will be available for you to examine. Pick one or two and make a habit drawing. Label the leaves (aka, fronds), stems, and roots. Find and draw the vascular tissue and stomata in the leaves.

The Fern Sporangia*. Fern sporangia are typically found in clusters called sori (sorus, singular) on the lower surfaces of sporophylls. In some ferns, the sori are covered with a layer of sterile tissue called an indusium. In others, the sori are exposed throughout development. Each sporangium in the sorus consists of a stalk and a sporangium. The mature sporangium has an outer sporangial wall consisting of a ridge of thick walled cells called an annulus, two lip cells, and a number of thin, fragile wall cells. Inside the sporangial wall are a number of haploid spores. Slightly younger sporangia have a layer of nutritive cells called the tapetum between the sporangium wall and the developing spores. At this stage, most of the spores are grouped into clusters of four (called tetrads). Why? The youngest sporangia that you will be able to recognize easily will lack spores. In the location where spores will be found later, there are a number of spore mother cells (aka, sporocytes). Are the spore mother cells diploid or haploid? Are the cells of the tapetum and the sporangial wall diploid or haploid?

Draw a sorus showing sporangia and the indusium (if present). Ferns actively release their spores from the sporangium. Watch some sporangia, and determine how the spores are released. Draw a mature sporangium and label the spores, sporangium wall, lip cells, annulus, and stalk. Find and draw a younger sporangium and label the tetrads (groups of four spores) and tapetum. Find and draw a very young sporangium and label the sporogenous tissue (the tissue consisting of spore mother cells.

Spore Germination. When spores land in an appropriate environment, they will germinate and give rise to a gametophyte. Fern spores germinate in a bipolar manner. A filament with green chloroplasts grows upward and will develop into the photosynthetic portion of the gametophyte. Another filament grows downward as a rhizoid. Its cells lack green chloroplasts. Draw a germinating spore, if available, and show the old spore wall, the green filament, and the rhizoid.

The Gametophyte*. The typical fern gametophyte (aka, prothallus) is a flat, green, heart-shaped structure that is one to a few cells thick and has numerous rhizoids extending from its lower surface into the soil. Pick a gametophyte from soil, wash it free of soil and mount it on a slide. Make a habit sketch of the upper and lower surfaces labeling the photosynthetic cells and the rhizoids. Draw one photosynthetic cell in detail. How is this plant similar to some of the green algae you observed? How is it different?

The Gametangia*. Both antheridia and archegonia may be found on the same gametophyte. They will be found on the lower surface of the gametophyte. Why may this be an adaptation? Antheridia will be found primarily from the area of rhizoids to the area near the notch of the gametophyte. Archegonia will be found almost exclusively near the notch. Why do you think this is so?

Antheridia are igloo-shaped structures that extend from the lower surface of the gametophyte. Mature antheridia have a wall consisting of several jacket cells and a round cap or operculum. The center of the antheridium is filled with several coiled up sperm cells (they look like little Danish pastries). Younger antheridia are filled with cube shaped spermatogenous cells. Mount a gametophyte bottom side up on a slide. Find and draw mature antheridia labeling the jacket cells, operculum, and sperm. Find and draw a young antheridium and label the spermatogenous cells. If you see sperm release, draw a mature sperm.

Archegonia are partially buried in the tissue of the gametophyte. The single egg is embedded in the tissue of the gametophyte. It is surrounded by a jacket of cells called the venter of the archegonium. This jacket may be hard to distinguish from the somatic cells of the gametophyte. A canal called the neck canal leads from the egg to the outside of the archegonium. The neck canal is surrounded by neck cells. The proximal (nearest the egg) portion of the neck is surrounded by somatic tissue of the gametophyte. The distal portion of the neck extends out from the surface of the gametophyte. The neck canal and egg are often a dark brown color. Therefore, archegonia can be found by looking for little brown lollipops in the lower surface of the gametophyte. Find and draw a mature archegonium. Label the neck, neck canal, and the egg. If you can discern it, also label the venter. Draw an archegonium in side view and the view from the tip of the neck to the egg. How many rows of cells make up the neck?

The Embryo and Juvenile Sporophyte*. One or a couple of the zygotes formed from the fertilization of eggs on a gametophyte will develop into an embryo(s). A young embryo looks like a green ball of cells embedded in the gametophyte. The venter of the old archegonium enlarges and provides nutrients to the embryo. The embryo quickly develops a shoot axis with leaf primordia and a primary root axis. At the junction between the root an shoot axes is a lateral swelling of the embryo that stays embedded in the old archegonium. This swelling is the foot. It continues to draw nutrients from the gametophyte. The first leaf of the juvenile sporophyte usually comes up through the notch of the gametophyte.

Examine gametophytes that are supporting young sporophytes. Draw and label the shoot axis, primary root, and foot of the young sporophyte. If you can find one, draw a spherical embryo embedded in a gametophyte.

Summary. Take all your drawings of the fern and arrange them in a life cycle. Compare the life cycle you construct to that illustrated in you text. Arrange the fern life cycle in tabular form and make it the basis for comparison with the life cycles of the other groups of Land Plants we will study.


Embryophytes II - The Bryophytes

The bryophytes consist of the three lineages of Land Plants which have dominant gametophytes and dependent sporophytes. That means that the gametophytes are free-living, but the sporophytes never separate from their attachment to the old archegonium. As a rule, the bryophytes have the most structurally complex of gametophytes and gametangia found in the Land Plants and the least structurally complex sporophytes. All bryophytes have sporophytes that have a foot, a stalk (the seta) and a sporangium (the capsule). All have no vascular tissue in the sporophyte. The three lineages are the Bryophyta (mosses), Hepatophyta (liverworts), and Anthocerophyta (hornworts). Bryophytes can only be metabolically active when they are in very moist conditions. How is it then that some bryophytes can survive in deserts and on tree bark and rocks? Bryophytes are discussed in Chapter 18 of your text.

The Mosses - Bryophyta. Mosses have the most complex gametophytes of any of the land plants. A gametophyte* looks superficially like the sporophyte of a vascular plant. There is a central stem-like axis from which extend several leaf-like structures. There is an apical growing point. The axis may branch. There are root-like strands, the rhizoids, which anchor the plant in the ground. Examine a gametophyte carefully with the microscope and draw it. Label the axis, "leaves", and rhizoids. Show why the gametophyte actually does not have true stems, leaves, and roots. Gametophytes of most mosses develop from a stage, the protonema, that looks like a filamentous green alga. Find and draw a protonema (or rhizoids) and indicate how it can be distinguished from a green alga.

From live material and from Mnium* sp. in your kits, find male gametophytes. The apices of male gametophytes form a flower-like splash cup with clusters of antheridia in the center. Make a longitudinal section of the apex of a male plant and draw the antheridial head, labeling the "leaves" of the splash cup, the sterile filaments that surround the antheridia, and the antheridia. Draw one antheridium in detail, labeling the sterile jacket and the spermatogenous tissue. Supplement your observations of free hand sections with observations of sections on prepared slides. If you see sperm release in living material, draw the sperm.

From live material and from Mnium* sp. in your kits, find female gametophytes with attached sporophytes. Draw an intact female gametophyte and sporophyte. Label the gametophyte and the seta and sporangium of the sporophyte. There may be a cap of tissue covering the sporangium. This is called the calyptra (the apex of the old archegonium). Pull the sporophyte out of the gametophyte and set it aside. Make a longitudinal section of the apex of the female gametophyte, and look for stalked archegonia which did not get successfully fertilized. Draw an archegonium showing the stalk, the venter containing an egg, the egg, the neck and the neck canal. You should supplement your observations of free hand sections with observations of a prepared slide of an archegonial head.

Examine the sporophyte you set aside. If a calyptra covers the sporangium, gently remove it. Draw and label the foot, the seta, and the sporangium. Examine the sporangium in detail with both the dissecting microscope and the compound microscope. Locate and draw the where stomata occur on the capsule. How do these stomata differ from those of vascular plants? There will be a small cap on the apex of the sporangium. This is the operculum. Label it on your drawing. Gently remove the operculum and open the sporangium. There will be a ring of inward pointing teeth below where the operculum was attached. This is the peristome, and the teeth are called peristome teeth. What do the peristome teeth do when you remove the operculum? Below the peristome are the spores. Squeeze out some spores, mount them on a slide and draw a spore. What about the spore suggests that it is a product of meiosis?

Finally, examine a gametophyte of Sphagnum* sp., peat moss. Make a habit drawing and a detailed drawing of a section of an axis. What characteristic(s) of the "leaves" of Sphagnum make it so useful in gardening?

The Liverworts - Hepatophyta. There are two major growth habits of liverworts, thallose and leafy. Thallose liverworts have flattened gametophytes while those of leafy liverworts appear to be superficially similar to mosses. The sporophytes of liverworts are the simplest sporophytes found among extant Land Plants. We will examine some examples thallose liverworts.

Examine a living gametophyte of the thallose liverwort, Reboulia* sp., and a preserved gametophyte of Marchantia polymorpha* from your kit. Make a habit drawing of each. Show the branching pattern of the thallus in each and the rhizoids on the lower surface. How are the two liverworts similar? How are they different? What evidence is there that M. polymorpha is capable of asexual reproduction?

Marchantia polymorpha is dioecious with separate male and female gametophytes. Male gametophytes produce antheridia in flower-like splash cups on erect structures called antheridiophores. Draw the habit and label a male thallus with an antheridiophore. Section an antheridiophore and find the antheridia. Supplement your drawing with observations from prepared sections. Draw and label antheridia. How are they similar to the antheridia of mosses? Reboulia sp. is monoecious. Indicate where its antheridia are located on a gametophyte.

Archegonia are borne on upright, umbrella-shaped structures called archegoniophores. Draw the habit of a female gametophyte of M. polymorpha and label the archegoniophore. Section the archegoniophore and locate the archegonia. Draw one archegonium in detail, labeling the venter, egg, neck, and neck canal. Supplement your observations with observations of a prepared section of an archegoniophore.

When eggs are fertilized, the venter of the archegonium expands to become a calyptra around the developing embryo. Section through a calyptra of a living specimen of Reboulia sp. and locate and draw an embryo. The embryo eventually develops into a mature sporophyte with a foot, seta, and a sporangium. Draw a mature sporophyte of Reboulia sp. if any are available. Draw a longitudinal section of a mature sporophyte of M. polymorpha* from a prepared slide. Label the foot, seta, sporangium, spores, and elaters (acellular filaments found with the spores in the sporangium). What is the fate of the archegoniophore during sporophyte development?

Other liverworts may be available for you to observe.

The Hornworts - Anthocerophyta. Hornworts have the simplest gametophytes of the bryophytes. Examine and draw a habit of the hornwort Phaeoceros laevis* from a demonstration. To which Land Plant gametophyte you have seen is it most similar? Why? Examine and draw a single cell of P. laevis. How is it like the cell of a green alga? You may find colonies of Nostoc in the gametophytes of this hornwort. What may they be doing there?

If gametangia of P. laevis are present, they will be demonstrated. You do not have to draw them.

Make a habit sketch of a gametophyte with an attached sporophyte. This may be a demonstration of live material. Examine and draw a prepared slide of a gametophyte with an attached sporophyte. Label the involucre (the sheath of gametophyte tissue that surrounds the base of the sporophyte) and the foot, seta, and sporangium of the sporophyte. Is the seta all that obvious?


Embryophytes III - Vascular Plants with Fern-like Life Cycles, the Lycopods (Lycophyta) and Horsetails (Sphenophyta).

Several groups of vascular plants evolved at approximately the same time as the ferns, and many of them had a similar life cycle to the ferns. That is, they had free-living sporophytes and free-living gametophytes. For this reason, these plants are often called "fern allies." Of these plants, two lineages still have a few extant species. These groups are the Lycophyta, or lycopods, and the Sphenophyta, or horsetails. We will examine some examples of these plants, emphasizing primarily the sporophyte stages. These plants are covered in Chapter 19 of your text.

1. Lycopods. The lycopods are all characterized by having microphylls, leaves which typically have a single vein. The club mosses are classically placed in the single genus Lycopodium, though modern taxonomists are, as your text points out, dividing it into several genera. This group of lycopods, like the ferns and mosses you observed, produces one kind of spore which germinates to give rise to a single type of gametophyte that develops both antheridia and archegonia. Such plants are termed homosporous. The spike mosses of the genus Selaginella and the quillworts of the genus Isoetes produce two types of spores, large megaspores and small microspores. The former produce megagametophytes, and the latter produce microgametophytes. Megagametophytes support only archegonia, and microgametophytes support only antheridia. Plants with these two types of spores are termed heterosporous. We will examine fertile sporophytes of a clubmoss and a spikemoss and the gametophyte stages of the latter.

a. Lycopodium*. Examine and draw the sporophyte of Lycopodium sp. from your kit. Note the vegetative portion of the plant and the cone, or strobilus, which contains sporophylls that support sporangia. Label the roots, stems, leaves, and cone. Crush a sporangium and draw the spores. Supplement your observation of the cone with examination of a prepared slide of a cone. Draw one sporophyll in detail, labeling the sporophyll, the sporangium, the tapetum (if present), and the spores. Observe that all the sporangia and their spores are of approximately the same size. Watch what happens when Lycopodium spores are tossed into an open flame. What does this tell you about spores? Label four characteristics of Lycopodium that indicate that this is the sporophyte stage of a vascular plant.

We have no gametophytes of Lycopodium available, but be familiar with the life cycle in your text.

b. Selaginella*. Examine and draw a sporophyte of Selaginella. Label the roots (on rhizophores), stems, leaves, and cones. Examine the base of the upper surface of a leaf and try to observe a ligule (if you do not see one on live material, you can see some on prepared slides). This structure is typical of the heterosporous lycopods. Observe that the cones, if present, contain sporangia of different sizes and colors. The larger, light colored sporangia are megasporangia, and the smaller, orange sporangia are microsporangia. Supplement your observations of whole cones with observations of a prepared section of a cone. Draw a sporophyll with a megasporangium and one with a microsporangium. Label the sporophyll, sporangium, tapetum (if present), and spores. How many spores are in a megasporangium? A microsporangium?

Examine and draw the demonstration slide with microgametophytes and a megagametophyte. The latter has a young sporophyte emerging from it. How do the gametophytes differ from the spores? How do you know that a young sporophyte is emerging from the megagametophyte? Indicate on your drawing where the archegonium was located on the megagametophyte. Does the megagametophyte remind you of any parts of other plants you have seen? What?

c. Isoetes. The quillworts are also heterosporous lycopods. Examine a herbarium specimen to see how big a microphyll can be.

d. Fossil Lycopods. Observe the specimens of Carboniferous lycopods. How did some of them differ from extant lycopods?

2. Horsetails. All extant horsetails are classified in the single genus Equisetum. They are also commonly known as scouring rushes. Why? Examine and draw live sporophytes of E. hyemale* and preserved specimens of E. arvense* from your kits. How do these two species differ? Label the leaves, branches (if present), stems, roots, and cones. The cones support specialized branches, the sporangiophores, that bear several sporangia each. Examine and draw a prepared section of a cone. Draw one sporangiophore and label the sporangia and spores. Are these plants homosporous or heterosporous? Why? The leaves of horsetails are very small and look like microphylls. Examine a fossil horsetail, Sphenophyllum, and explain why horsetails have megaphylls as vegetative leaves.

Examine and draw prepared slides of gametophytes of Equisetum. Label the somatic photosynthetic tissue and the rhizoids. Draw an archegonium and an antheridium. Label the neck, neck canal, venter and egg in the former and the jacket and sperm in the latter. To what other plants are these gametangia most similar?


Embryophytes IV - The Seed Plants I, the Sporophytes

Seed Plants are a monophyletic group of heterosporous vascular plants. All have gametophytes that "germinate" from spores and complete their development in the tissue of the sporophyte generation. Their gametophytes are the simplest of all land plant gametophytes, and their sporophytes are the most complex. The microgametophytes germinate from spores in the microsporangium, or pollen sac, are moved to female tissue as pollen, and complete development in the female tissue that supports the megagametophyte. Mature microgametophytes lack antheridia and produce only two sperm each. The megagametophyte germinates from a megaspore within the megasporangium, or nucellus. The nucellus is protected in a specialized covering called the integuments. The combined integuments, nucellus, and megagametophyte are termed the ovule. An egg or eggs develop in the mature megagametophyte. The egg is fertilized by a sperm, and the zygote develops into an embryo within the tissue of the megagametophyte in gymnosperms or the endosperm in angiosperms. The ovule remains attached to the parent sporophyte after fertilization until it has matured into a seed. The sporangium-bearing structures of seed plants are often arranged on modified shoot tips called cones. There are five extant lineages of seed plants: the cycads (Cycadophyta), Ginkgo biloba (Ginkgophyta), the conifers (Coniferophyta), the gnetophytes (Gnetophyta), and the angiosperms (Anthophyta). The first four groups have ovules that develop in contact with the "outside world", and they are informally called gymnosperms. The angiosperms produce ovules in enclosed spaces called carpels, and the carpels develop into fruits. We will study examples of the cycads, Ginkgo, the conifers, and the angiosperms. Rather than study them as separate groups, we will take a comparative approach studying them all at comparable stages of the life cycle. The Seed Plants are discussed in Chapters 20-22 in your text.

Habit

Cycads. Cycads are mostly small trees found in tropical to subtropical regions of the world. Most of them grow best in open, sunny areas. The sporophytes are dioecious, i.e., there are separate male (staminate) and female (ovulate) trees. Draw the shoot of Zamia sp.*from a specimen in the greenhouse. Label the leaves, stem, and cones (either male or female). From a plant of the other sex, draw the alternate type of cone to scale.

Ginkgo biloba*. This is the only extant species of the Ginkgophyta. Ginkgo trees are also known as maidenhair trees because the delicate veining of their triangular leaves looks like the pubic hair of pubescent girls. This common name obviously has preVictorian origins. Ginkgos are native to China, although all remaining trees may be domesticated. They have been planted as ornamental trees around the world. They grow into large trees in temperate to subtropical climates, and they seem little affected by air pollution or pathogens. An attractive feature is that their deciduous leaves turn bright yellow all at once in the fall. Like cycads, ginkgos are dioecious with separate staminate and ovulate trees. The male trees are the trees of choice for most plantings because the fleshy seeds of the female trees become rancid smelling in the fall. Make a habit drawing of a ginkgo with a detailed drawing of the leaves and their origin on short spur branches. Draw and label a branch from a male tree showing the staminate cones, and draw and label a branch from a female tree showing the ovulate appendages with their paired ovules.

Conifers. Most conifers are trees, though a number are shrubs. They are found throughout the world, but are most abundant in temperate to cool temperate regions. Most have needle-like leaves with thick cuticles, and most are evergreen. An important genus of conifers is the genus Pinus*, the pines. Pines are trees with their needles arranged in clusters on short spur branches (fascicles). Many pines are important lumber trees and sources of fiber for paper. Others are ornamental. Unlike the ginkgos and cycads, pines are monoecious with staminate and ovulate cones forming on the same tree. Staminate cones form in the spring, shed pollen and fall off the tree. Ovulate cones take two years to mature, and tend to stay on the tree even after the seeds are shed. Draw the habit of a pine tree, and make a detailed drawing of a branch or branches that show the leaves in fascicles, evidence for the age (in years) of the oldest leaves, terminal first-year ovulate cones, staminate cones, second-year ovulate cones, and mature ovulate cones.

Flowering Plants, Angiosperms. The biggest group of Land Plants is the angiosperms. Unlike the gymnosperms listed above, the angiosperms usually have the pollen sacs and ovules located in a common cone, the flower. Also, unlike the gymnosperms, many of the angiosperms are herbaceous (nonwoody). The unique morphological feature of the flowering plants is that the ovules are closed up within a folded over megasporophyll, i.e., the ovules are found in chambers called carpels. As a result, seeds develop inside fruits. Make a habit drawing of the flowering plant you are using for your flower to fruit exercise*. Show the roots, stem(s), leaves, inflorescence, flowers, and fruits. Remember, you should choose a plant with complete flowers.


Seed Plants II - Microsporophylls and Pollen Development

All Seed Plants produce microspores in microsporangia on microsporophylls. Microsporophylls are typically borne on modified shoot axes that are variations on the cone theme. They usually have more than one microsporangium per sporophyll. Microsporangia have numerous microspore mother cells and a distinct tapetum when young. A synonym for a microsporangium is the pollen sac. This is because, after microsporogenesis in the sporangium, the spores "germinate" to become the young microgametophytes called pollen grains. Pollen grains mature to the point that they consist of at least a tube cell (which comprises the "plant body" of the microgametophyte) and a cell that will be the ancestor to the two sperm. The cells of the microgametophyte then become dormant. At the same time that the pollen cells are developing from the microspores, a thick, protective wall is developing around the pollen grain. Mature pollen grains are shed from the pollen sacs, and microgametophyte development only continues when the pollen lands on the appropriate female structures of the same species. We will concentrate on pollen development in at least one example from gymnosperms and one example from flowering plants.

Cycads. Draw a male cone from Zamia *sp. and label the sporophylls. Take one sporophyll and draw its lower surface, labeling the pollen sacs. Crush some pollen sacs in a drop of water on a slide, and draw some mature pollen grains. If we have fresh, young male cones, crush several pollen sacs from different parts of the cone in a drop of water on a slide. Look for and draw tetrads of microspores, single microspores (one cell only), developing pollen (2 - 4 cells), and mature pollen. In the pollen, try to observe and label the prothallial cell, tube cell, and the generative cell. Which cell will be the ancestor of the sperm?

Ginkgo*. Draw the habit of a male cone and label the microsporophylls. Draw a single microsporophyll and label the pollen sacs. How many are there on each sporophyll? Crush a pollen sac in a drop of water on a slide and draw mature pollen grains. If we have male cones of various ages, crush a number of pollen sacs on a slide and draw the stages of pollen development showing microspores, developing and mature pollen. In the pollen, try to observe the two prothallial cells, the tube cell, and the generative cell.

Pinus*. Draw a male cone of pine, labeling the microsporophylls. Make a free hand section of a male cone and locate the pollen sacs on the sporophylls. How many pollen sacs are on each sporophyll? Draw and label. Supplement your drawing with observations from a prepared of a male cone. Crush a pollen sac on a slide, and draw the pollen. What characteristic of the pollen is likely to be an adaptation to wind pollination? Observe a developing pollen grain on the demonstration microscope and draw it. What type of nuclear division is taking place in that pollen grain?

Angiosperms*. The microsporophylls of flowering plants are the stamens. Stamens are found in flowers. A stamen consists of a filament and an anther. The pollen sacs are part of the anther. Draw a flower of your plant* and label the stamens. Remove a stamen and draw and label the filament and the anther. How many pollen sacs are found in the anther of your plant. Crush an anther on a slide and draw the pollen. If you have flowers of several ages on your plant, crush several anthers from several ages of flowers and draw the stages of development from microspores to mature pollen. You probably will not be able to count cells in the pollen of your plant.

To supplement the observations of your own plant, observe prepared sections of Lilium michiganense* anthers showing the stages of pollen sac and pollen development from the microspore mother cell stage to the mature pollen stage. How long is the tapetum present in the pollen sacs of this lily? What is its function? How many cells are in a mature pollen grain? What are they? Which cells found in gymnosperm pollen are not present in angiosperm pollen?


Seed Plants III - Ovules, Megagametophytes, Microgametophytes, and Seed Development.

The site of megasporogenesis and megagametophyte development in seed plants is the ovule. It is also the site of fertilization and embryo development. During embryo development, the ovule becomes a seed.

Ovules may be found on megasporophylls or on modified branches (the basis for this distinction is a subject for a more advanced course). Ovulary appendages are arranged in cones of one type or another in all seed plants except ginkgos. Each ovule has an outer protective layer called the integument(s). A channel through the integument(s) is found at the apex of the ovule. The channel is called the micropyle. The micropyle leads to a chamber above the megasporangium. The micropyle allows fertilization to take place. Each ovule contains a single megasporangium, or nucellus. Each nucellus has one megaspore mother cell develop in it. There is no tapetum, per se, in the nucellus. A single megaspore typically survives meiosis of the megaspore mom and develops into a single megagametophyte. Megagametophytes go through a coenocytic phase and become multicellular by cleavage of the coenocyte.

Megagametophytes are relatively large and multicellular in gymnosperms, and they may produce several eggs. The eggs of gymnosperms are formed in archegonia except in the gnetophyte genera Gnetum and Welwitschia. The zygotes and embryos of gymnosperms are nourished by food stored in the haploid tissue of the megagametophyte.

Megagametophytes (aka, embryo sacs) of angiosperms have relatively few cells. They produce a single egg and no archegonium. The zygote and embryo are nourished by a polyploid tissue, the endosperm, which is a result of double fertilization.

In gymnosperms, the ovule is also the site of microgametophyte maturation. Pollen grains enter the ovule through the micropyle, land on or near the nucellus, and germinate to form a pollen tube. Cell divisions occur in the microgametophyte resulting in one cell dividing to produce two sperm inside the pollen tube. When the pollen tube penetrates through the nucellus, the tip of the pollen tube ruptures to release the sperm. The sperm may then fertilize the eggs in the megagametophyte.

In flowering plants only, the ovules are found inside a chamber formed by a closed megasporophyll. The chamber is a locule, and the megasporophyll is a carpel. A flower may have one or more carpels, and carpels may be single or fused to form a multicarpelate pistil. After fertilization, as the ovules develop as seeds, the carpel(s) develop(s) as fruit.

The presence of the carpel in flowering plants prevents the pollen from reaching the ovule directly. Therefore, microgametophyte development from the pollen grain is initiated on the receptive surface (the stigma) of the pistil. A pollen tube grows from the stigma through the style tissue of the carpel to the ovule and through the micropyle. As in gymnosperm pollen, cell division results in the production of two sperm. After the pollen tube penetrates the nucellus, the sperm are released by the dissolution of the tip of the pollen tube.

Following successful fertilization, the integuments of the ovule develop into the seed coat. The nucellus remains as a thin layer of tissue covering the nutritive tissue. The nutritive tissue surrounds the embryo. In flowering plants, the carpel simultaneously develops into the fruit wall.

In this lab we will try to get an idea of ovule development in Seed Plants. We will treat all gymnosperms as essentially similar and will illustrate various points in ovule, megagametophyte, and microgametophyte development with the best available examples.

Gymnosperm ovules. If you have not already done so, draw and label the habit of a female cone of Zamia*, the ovulary appendages of Ginkgo*, and first and second year cones of Pinus.* Remove a single ovulary appendage from each and draw the ovules intact, labeling the integument and the micropyle. Be sure to indicate the number of ovules on each type of appendage.

Young ovules. Section an ovule of Ginkgo lengthwise through the micropyle and draw it on low power of your microscope. Label the integument, nucellus, pollen chamber, and megagametophyte (if present). Also, label and pollen found in the pollen chamber. How did the pollen get there? Is it all ginkgo pollen?

Compare the ovule of Ginkgo to that of Pinus in the first year. Use a prepared slide. What similarities, differences do you see?

Ovules with mature megagametophytes and microgametophytes. Examine and draw a mature ovule of Zamia from a prepared slide. Label the integument, nucellus, megagametophyte, archegonium(a), and egg(s). Also label the pollen tube(s) of the microgametophytes that are penetrating the nucellus. Under high power, examine and draw the sperm and/or developing sperm. At what point will Zamia pollen tubes burst to release their sperm?

Compare the ovule of Zamia to that of a late summer, second year cone of Pinus. A prepared section will be set up on the teaching microscope. Label the comparable parts. Be sure to label the pollen tubes in the nucellus. At what point will the pollen tubes of Pinus release their sperm? What is the major difference between the sperm of cycads and conifers?

Seeds. Embryos develop in the seeds of gymnosperms embedded in the tissue of the megagametophyte. Dissect the seed from a mature cone of Pinus and make a habit sketch. How does it differ from an ovule? The pine nuts are the megagametophytes from shelled seeds of certain large-seeded pines. Dissect a pine nut and draw the embryo in it. Label which end of the pine nut is the micropylar end. How can you tell?

Angiosperm carpels and ovules. You should use your flower-to-fruit plant as your example for angiosperm ovule and fruit development at the habit level. If you have not already done so, make habit drawings of the reproductive structures of your plant from the flower bud to the mature fruit stage. At each stage, dissect the gynoecium (all the pistils) and determine the number of carpels per flower. Does the number of carpels vary throughout development? Label whether the carpels are in separate pistils or fused into a single pistil. Label the ovary, style, and stigma of a pistil. Locate and draw the location of pollen grains on the pistil. Draw the arrangement of ovules in a carpel. Draw and label the ovules in the bud and mature flower and the developing seeds from the post-fertilization flower to the mature fruit. How does the gynoecium change during fruit development? Is tissue other than that of the carpel(s) proper involved in the development of the fruit?

Microgametophyte development. Flowering plant pollen can be fooled into maturing in a sugar solution. Draw mature microgametophytes from the demonstration slide on the teaching microscope. Label the pollen grain, pollen tube, tube cell nucleus, and sperm. Where would this development be taking place on your plant?

Immature ovules. Draw an ovule with integuments, nucellus, and megaspore mother cell from a prepared slide on the teaching microscope.

Mature ovules and megagametophytes. Embryo sacs mature fairly quickly in angiosperms. The mature embryo sac typically consists of seven cells. Three antipodal cells form at the end of the embryo sac furthest from the micropyle. Three cells of the egg apparatus, the egg and two synergids, form at the micropylar end of the embryo sac. The bulk of the embryo sac is taken up with a large, binucleate central cell. The two nuclei are called the polar nuclei. Draw a median longitudinal section through an ovule of Lilium michiganense* from a prepared slide on the teaching microscope. Label the integuments, nucellus, megagametophyte, synergids, egg, central cell with polar nuclei, and antipodal cells.

Double fertilization. Both sperm nuclei of a pollen tube fuse with nuclei of the embryo sac. One sperm fuses with the egg to produce a zygote. The other fuses with the two polar nuclei to form a polyploid primary endosperm nucleus. Only the zygote and primary endosperm cell (nee, the central cell) survive. The zygote becomes the embryo, and the primary endosperm cell becomes the endosperm, the nutritive tissue of the seed. Draw double fertilization from a prepared slide on the teaching microscope. Label the fusing nuclei.

Seeds. Section the seeds of your plant and find and draw the embryo (if your seeds are big enough). If not, dissect some seeds that will be available in class.

Fruits. Identify the type of fruit that your plant produces. Label the parts of the gynoecium that have become part of the fruit. Eat and enjoy the examples of fruits we have brought to lab.


Embryophytes (Land Plants) I: Life Cycle, the fern example: Checklist for Notebook

Adiantum sp., the maidenhair fern

Somatic Diploid, the sporophyte

__x___Habit of sporophyte, Label __x__stem (or rhizome), __x__adventitious roots, __x__leaf (or frond), __x__fiddlehead (unrolling leaf)

Site of meiosis and products of meiosis, the sporangia and spores

__x___Habit of sporophyll, Label __x__sorus and false indusium

___x__Detail of sori at 10x and 40x, Label __x__premeiotic-meiotic sporangium with ___x_stalk, ___x_annulus, __x__lip cells, __x__tapetum, __x__spore mother cells (sporocytes) or young tetrads; ___x_maturing sporangium with __x__ stalk, __x__annulus, __x__lip cells, __x__tapetum, __x__spore separating from tetrads, _x___triradiate ridge on spore; __x__mature sporangium with __x__stalk, __x__annulus, __x__lip cells, __x__mature spores, _x___spore with triradiate ridge

Somatic Haploid, the gametophyte

__x___Habit of gametophyte, Label __x__photosynthetic tissue, ___x_apical notch, __x__rhizoids, __x__detail of somatic cells of photosynthetic tissue showing __x__chloroplasts

Sites of gamete development and fertilization, the gametangia

__x___Antheridium at 10x and 40x, Label, __x__antheridial wall, __x__operculum, __x__spermatogenous tissue, __x__maturing sperm, __o__released sperm

__x___Archegonium at 10x and 40x, Label, __x__neck, __x__neck canal cells in young archegonium, __x__neck canal in mature archegonium, __x__venter, __x__egg, __x__embryo in swollen archegonium

Young sporophyte arising from gametophyte

__x___Habit of young sporophyte emerging from under gametophyte, Label _x___juvenile leaf of young sporophyte, __x__parent gametophyte (Mom)


Embryophytes (Land Plants) II: the Bryophytes: Checklist for Notebook

Mosses, Mnium sp., Atrichum sp., Bartramia pomiformis, Dicranum sp. , use preserved and fresh material and/or prepared slides. Make sure you illustrate all the stages. You may use whatever combination of specimens you wish.

Somatic diploid, the dependent sporophyte

___x__Habit of sporophyte attached to gametophyte, Label, __x__capsule (=sporangium), __x__calyptra (=old archegonium), _x___operculum, __x__seta, _x___foot (pull out of gametophyte)

Site of meiosis and products of meiosis, the sporangium and spores

__x___Details of sporangium using dissecting scope and 4x, 10x, and/or 40x objectives on compound scope, Label, __x__operculum, __x__peristome and peristome teeth, __x__stomata in epidermis of capsule, __o__spores showing __o__triradiate ridge

Somatic Haploid, the gametophyte

__x___Protonema (or rhizoids) use 10x or 40x, Label, _x___branching filament, __x__slanted cross walls

__x___Habit of "leafy" gametophyte, Label, ___x_rhizoids, __x__stem-like axis, __x__"leaf"

Sites of gamete development and fertilization, the gametangia

__x___Splash cup of male gametophyte, use dissecting scope, and 10x and 40x, Label __x__"leaves" that form walls of the cup, __x__central region containing antheridia, __x__sterile filaments, __x__young antheridia with spermatogenous cells and sterile jacket, _x___mature antheridium with sterile jacket, ____sperm release, ____released sperm.

__x___Female gametophyte with attached sporophyte (may be same as above), use dissecting scope, and 10x and 40x, Label, _x___archegonium with ___x_stalk, __x__venter, _x___egg, __x__neck, __x__neck canal, __o__neck canal cells, __o__attachment of foot in old archegonium

Liverworts, the thallose liverworts Marchantia polymorpha and Reboulia sp. , use preserved and fresh material and/or prepared slides. Make sure you illustrate all the stages. You may use whatever combination of specimens you wish.

Somatic diploid, the dependent sporophyte, as well as site of meiosis and products of meiosis, the spores

__x____Habit of sporophyte attached to gametophyte, living Reboulia sp. and prepared slide of M. polymorpha. Use dissecting scope. Label, __x__calyptra and capsule __x__ on live specimen, __x__foot embedded in archegoniophore of gametophyte, _x___seta, __x__capsule wall, __x__spores, __x__elaters, __0__young sporophyte with tetrads of spores, __0__younger sporophyte with premeiotic sporogenous cells

Somatic haploid, the gametophyte

__x___Habit of living gametophyte. Label, __x__photosynthetic portion of thallus, __x__apical notch, __x__midrib, ___x_gemma cup, __x__a gemma, __o__rhizoids and scales

Sites of gamete development and fertilization, the gametangia

__x___Antheridial patch of Reboulia sp are in a sessile purple patch near the base of the archegoniophore.

___x__Archegoniophore of M. polymorpha from live material, kit, and slide. Label, __x__stalk and __x__splash cup of antheridiophore, __x__antheridial chamber in longitudinal section of antheridiophore, _x___antheridium with __x__sterile jacket and __x__sperm, __x__antheridium with spermatogenous tissue

__x___Gametophyte of Reboulia sp. with archegoniophore.

___x___Female gametophyte of M. polymorpha from live material, kit, and prepared slide. Label, __x__stalk and __x__cap of archegoniophore, __x__archegonium with ___x_stalk, ___x_venter, ___x_egg, __x__neck, __x__neck canal, _o___neck canal cells, _x___archegonium (now calyptra) with __x__embryo

Leafy liverwort, Porella sp.

___x__Habit showing __x__"leafy" gametophyte axis, __x__sporophyte with __x__ seta and __x__sporangium (capsule)

Hornworts, Phaeoceros laevis

__x___Habit of gametophyte with attached sporophyte, Label, _x___gametophyte with __x__involucre, __x__somatic cell with single plastid, _x___sporophyte, with __x__foot, __o__elongation zone (sort of a seta), __x__sporangium (=capsule)


Embryophytes (Land Plants) III: the Seedless Vascular Plants: Checklist for Notebook

Lycophytes, the clubmosses (Lycopodium spp., s.l.), spikemosses (Selaginella spp.), and quillworts (Isoetes spp., not seen). Use preserved and fresh material and/or prepared slides. Make sure you illustrate all the stages. You may use whatever combination of specimens you wish.

Homosporous, nonligulate lycophytes Huperzia (Lycopodium) lucidulum, Diphasiastrum (Lycopodium) tristachyium, Lycopodium sp.

Somatic diploid, the independent sporophyte

__x___ Habit of sporophyte of all available species, Label, __x__stem, __x__microphyll leaf, __x__adventitious root, _x___cone (if present), __x__sporophyll and sporangium (if present), detail of leaf wet mount showing _x___xylem in single vein, __x__stoma

The site of meiosis and products of meiosis, the spores (prepared slide)

___x__Detail of cone showing __x__sporophyll, _x___sporangium with __x__sporangium wall and __x__spores, _x___spore showing triradiate ridge.

Heterosporous, ligulate lycophytes Selaginella apoda, S. lepidophylla, S. sp.

Somatic diploid, the independent sporophyte

__x___Habit of sporophyte of all available species, Label __x__stem, __x__microphyll leaf, __x__adventitious root on rhizophore, __x__cone (if present), detail of leaf wet mount showing __x__xylem in single vein, _x___ligule, __x__stoma

The site of meiosis and products of meiosis, the spores (live material and prepared slide)

___x__Detail of cone showing __x__microsporophyll and __x__microsporangium and __x__megasporophyll and __x__megasporangium, __x__detail of microsporangium showing __x__microsporophyll, ___x_microsporangium wall, __x__microspores, __x__detail of megasporangium showing __x__megasporophyll, ___x_megasporangium wall, __x__single tetrad of megaspores, ___x_detail of developing sporangium showing __o__sporangium wall, __o__tapetum, __o__sporogenous tissue

Somatic haploid, the gametophytes

__x___Habit of megagametophyte with __x__young sporophyte, Label, __x__megaspore wall, __x__megagametophyte, ___x_foot of young sporophyte, __x_primary shoot of young sporophyte, __x__primary root of young sporophyte; ___x_microgametophyte

Horsetails, Equisetum hyemale, E. arvense. Use preserved and fresh material and/or prepared slides. Make sure you illustrate all the stages. You may use whatever combination of specimens you wish.

Somatic diploid, the independent sporophyte (live specimen)

__x___Habit of the sporophyte showing aerial stem with __x__nodes, __x__internodes, __x__whorls of scale-like megaphyll leaves, __x__cones (if present), __x__branches (if present), __x__vegetative shoot (E. arvense), __x__fertile shoot (E. arvense), __x__rhizome with __x__whorles of leaves at node, __x__adventitious roots

The site of meiosis and products of meiosis, the spores (prepared slide)

__x___Detail of cone showing __x__central axis, __x__sporangiophores, __x__sporangia with __x__sporangium wall, __x__spores, __x__detail of spore with __x__elaters

Somatic haploid, the gametophytes, and sites of gamete formation and fertilization (prepared slide)

__x___Habit of antheridial gametophyte showing _x___rhizoids, __x__photosynthetic tissue, __x__antheridium with __x__sterile jacket, __x__sperm, ___o_antheridium with spermatogenous tissue

__x___Habit of archegonial gametophyte showing __x__rhizoids, __x__photosynthetic tissue, __x__archegonium with _x___venter, ___x_egg, __x__neck, __x__neck canal, __x__neck canal cells

Young sporophyte arising from gametophyte

___x__Habit of young sporophyte and parent gametophyte, Label __x__gametophyte, __x__foot of young sporophyte, __x__primary shoot of young sporophyte


Embryophytes (Land Plants) IV: the Seed Plants I: The Sporophytes: Checklist for Notebook

Cycads, Zamia furfuracea

__x___Habit male and/or female plant (draw reproductive structures of both plants), Label, _x___stem, __x__pinnately compound leaf, __o__coralloid root, __x__spent male cone, ____spent female cone

Ginkgophytes, Ginkgo bioloba

__x__Habit male and/or female tree (draw reproductive structures of both plants), Label, _x___stem, __x__spur branches, __x__leaf, ___x_unrolling leaf, __x__male cones (male tree), __x__ovuliferous appendages (female tree), ____ovules/developing seeds, ____pollination droplet on ovule

Conifers, Pinus spp.

__x___Habit tree, Label, __x__stem, ___x_1998 leaves, __x__1999 leaves, __x__new 2000 leaves, __x__fascicle of leaves (needles), __x__male cones, __x__1998 or older, female cones, __x__1999 female cone, __x__2000 female cone, ____pollination drop

Flowering plants, Your flower to fruit plant

__x___Habit, Label, __x__roots, __x__stem, __x__leaves, __x__flower bud, __x__open flower with __x__sepals, __x__petals (tepals if petals and sepals look alike), __x__stamens, __x__pistil(s), __x__fruit

Supplement with drawings of Lilium sp. (lily) and Prunus sp. (cherry) flowers and fruits from your kits.


Embryophytes (Land Plants) IV: the Seed Plants II: Microsporophylls and Pollen Development: Checklist for Notebook

Cycads - Not Covered

Ginkophytes, Ginkgo biloba

___x__Male cone, Label, __x__axis, __x__microsporophyll, __x__pollen sacs (=microsporangia), __x__immature pollen grain (40x objective) with __x__prothallial cells, __x__generative cell, and __x__tube cell, __x__mature pollen grain

Conifers, Pinus spp. (live material and prepared slide)

__x___Cluster of male cones at base of 2000 growth, __x__male cone, Label, __x__microsporophyll, __x__pollen sacs (=microsporangia), __x__pollen, __x__section of male cone (4x, 10x, and 40x), Label, __x__microsporophyll, ___x_pollen sac, __o__microspore with one cell, __x__developing pollen undergoing mitosis, __o__mature pollen with __o__prothallial cells, __o__generative cell, __o__tube cell, __x__living pollen (40x), Label, __x__air sacs, __x__pollen grain (and cells if seen)

Flowering plants, your plant and Lilium michiganense (demo in lecture)

__x___Androecium (all the stamens) of your plant, Label, ___x_stamen (=microsporophyll) with __x__filament, __x__anther with __x__connective, ___x_4 pollen sacs(=microsporangia), __x__pollen (40x) showing __x__pollen grain wall, __x__tube cell, ___x_generative cell

__x___Transverse sections of androecium of Lilium, Label __x__anthers with __x__connective and __x__4 pollen sacs, detail of pollen sac through pollen development showing __x__pollen sac wall, __x__tapetum (in early stages), __x__microspore mother cells, __x__meiosis I, __x__meiosis II or dyad, __x__tetrad of microspores, ____pollen development, __x__mature pollen with __o__ generative cell and __o__tube cell


Embryophytes (Land Plants) IV: the Seed Plants III: Ovules, Megagametophytes, Microgametophytes, and Seed Development: Checklist for Notebook

Gymnosperm ovules

Ginkgo biloba ovule with megagametophyte and microgametophyte

__x___Habit of ovuliferous appendage, Label, __x__appendage in situ on spur branch, __x__pair of ovules/developing seeds, __x__integuments, __x__micropyle, __o__pollination drop

__x___Freehand section of ovule/seed, Label, __x__integument, __x__micropyle, __x__nucellus (megasporangium) with __x__pollen chamber, __o__microgametophyte(s), __x__megagametophyte

Pinus sp. female cones with ovules

__x___Habit, 2000 (first year) cone, Label, __x__scale, __o__pollination drop

___x__Prepared section of first year cone, Label, __x__ovuliferous scale, __x__ovule with _x___integuments, __x__micropyle, __x__premeiotic nucellus (megasporangium), __o__pollen grain

___x__Habit, 1999 (second year) cone, Label, __x__scale (draw to scale with 2000 cone)

__x___Freehand section of second year cone and prepared section of second year ovule, Label where appropriate on each, __x__ovuliferous scale, __x__ovule, __x__integuments, __x__micropyle, __x__nucellus (megasporangium), __x__pollen tubes of microgametophytes growing through nucellus, __x__megagametophyte with __x__somatic tissue, __x__archegonium(a), __x__egg(s)

__x___Habit, mature cone, Label, __x__ovuliferous scale, __x__winged seed

Flowering plants, ovaries, ovules, fruits and seeds

Your plant and plants in lab, e.g., Iris

__x___Pistils of buds, mature flowers showing __x__stigma, __x__style, __x__ovary,__x__carpel(s) __x__ovule with __x__integument, __o__micropyle, __o__nucellus, __x__embryo sac with __o__egg apparatus, __o__central cell, __o__antipodals

__x___Developing and mature fruits (identify fruit type if possible, see text of one us) showing __x__fruit wall, _x___carpels, __x__developing and mature seeds, __o__embryo in seed

Lilium sp. from slide demo in lecture

__x___Developing microgametophytes (fooled in sugar water) showing __x__ pollen grain wall, __x__pollen tube with __x__tube cell, __x__tube cell nucleus, __x__ two sperm

___x__Section of young ovule with __x__developing integument, __x__nucellus with __x__megaspore mother cell

___x__Section of mature ovule with embryo sac showing, __x__integuments, __x__micropyle, __x__nucellus, __x__megagametophyte (embryo sac) with __x__three antipodal cells, __x__central cell with __x__polar nuclei, __x__three egg apparatus cells (egg, and synergids)

__x___Section of ovule immediately after fertilization with parts of the ovule labeled plus __x__fertilization of the egg (=zygote formation) and __x__fertilization of the central cell to form the primary endosperm

Seed development in Capsella bursa-pastoris from lecture demo, prepared sections

__x___Young seed with __x__ seed coat including integuments and nucellus, _x___free nuclear (coenocytic) endosperm, __x__embryo with __x__suspensor and __x__embryo proper

__x___Older seed with __x__seed coat, __x__endosperm, __x__embryo with __x__suspensor, __x__young embryo with developing cotyledons and primary root axis

__x___Mature seed with __x__seed coat, __x__cellular endosperm, __x__embryo with primary root, cotyledons, and primary shoot axis


Flower to Fruit Exercise and Checklist of Biological Principles that have been discovered in Botanical Critters: Checklist for Notebook

Flower to Fruit (see above as well)

___x__Habit of your plant, Label __x__the name of the plant, ___x_roots, __x__stem, __x__leaves, __x__flower bud, _x___mature flower, ___x_developing fruit, __x__mature fruit

__x__Flower bud, Label, __x__sepals, __x__petals, (or __x__ tepals), __x__stamens with __x__filaments and __x__anthers, __x__pistil(s) with __x__stigma, __x__style, __x__ovary, __x__carpel(s), __x__ovules (if present)

__x__Mature flower, Label, __x__sepals, __x__petals, (or __x__ tepals), __x__stamens with __x__filaments and __x__anthers, __x__pistil(s) with __x__stigma, __x__style, __x__ovary, __x__carpel(s), __x__ovule(s), __x__embryo sac - Also do this for the cherry from your kit

__x___Developing fruit, Label, _x___sepal, petal, and stamen scars, __x__old stigma and style, __x__ovary/fruit, __x__carpel(s), _x___developing seed(s)

__x___Mature (as possible) fruit, Label, __x__fruit type, __x__fruit wall, __x__carpel(s), __x__ seed(s), __x__endosperm, __x__embryo - Also do this for the cherry and the lily from your kit

Checklist of Principles

I expect that you should have at least 20 entries on this list. It's really easy to find 40-50 good ones, and I have had one student turn in over 100 (some of which are real stretches).