Seedless Plants (Kingdom: Plantae)

Bryophytes

Read the following sections in the class lecture notes on seedless plants:

Introduction
Alternation of Generations
Classification

Phylum: Bryophyta (Mosses)

Moss growing on a rock. img001.jpg (118712 bytes)

Read the section on Bryophytes in the class lecture notes.

1. Obtain live sporulating moss and identify the sporophyte and gametophyte generations.

Moss gametophytes and sporophytes
(Click on the photograph.)		 Image3.jpg (99407 bytes)

2. Draw the life cycle of a typical bryophyte such as moss. Your drawing should contain the following terms:

2N, N, sporophyte, sporangium, meiosis, spores, protonema, gametophyte, antheridium, sperm, archegonium, egg, fertilization

3. Observe a slide showing the antheridial head of Mnium (a moss). Begin using the scanning (4X) objective and then switch to the low power objective (10X). 

4. What is produced in this structure?

5. Show where the antheridium occurs on the live moss plant. Indicate where this structure occurs in the life cycle diagram that you prepared (above). 

Mnium (a moss) antheridial head Mnium antheridial head 40X.jpg (660893 bytes)
Mnium (a moss) antheridial head x40 img006.jpg (109676 bytes)
Mnium (a moss) antheridial aead x100 img007.jpg (97454 bytes)

6. Observe a slide showing the archegonial head of Mnium (a moss). Begin using the scanning (4X) objective and then switch to the low power objective (10X). 

7. What is produced in this structure?

8. Show where the archegonium occurs on the live moss plant. Indicate where this structure occurs in the life cycle diagram that you prepared (above). 

Moss archegonial head x40 moss archegonial head X 40.jpg (102370 bytes)
Moss archegonial head x100 moss archegonial head X 100.jpg (108610 bytes)

9. After the egg is fertilized, it grows and produces a sporophyte. A sporangium is found at the tip of the mature sporophyte. Click on the photograph below to view a sporangium.

Image3.jpg (99407 bytes)

10. Use a dissecting microscope to observe a slide of a moss capsule that has been cut longitudinally. 

11. What is produced within this structure?

12. Increase the magnification to 40X to view spores within the sporangium.

13. Be sure that you can identify the sporophyte and the sporangium on the live moss plant. Indicate where these structures occur in the life cycle diagram that you prepared (above). 

Moss capsule containing spores moss capsule.jpg (17691 bytes)    moss_capsule_1.jpg (21170 bytes)
Moss capsule x40 img003.jpg (103205 bytes)

14. Moss spores are dispersed by wind. Upon germination they produce filamentous structures called protonemata (singular is protonema). View a slide of moss protonemata. The protonema continues to grow and produces a gametophyte.

Moss protonema x100 img004.jpg (43424 bytes)

15. Indicate where the protonema occurs in the life cycle diagram that you prepared (above). 

Phylum: Hepatophyta (Liverworts)

1. Observe live Marchantia (a liverwort).  Find gemma cups. What is the function of gemma?

Marchantia (live) img010.jpg (100485 bytes)

2. Observe gemma cups, male and female gemetophytes in the specimens preserved in plastic. Are antheridia and archegonia present in the live Marchantia? What reproductive cells are produced by antheridia and archegonia? 

Marchantia preserved in plastic img011.jpg (62722 bytes)

Seedless Vascular Plants

Phylum: Pterophyta

Ferns

Fern gametophyte ferns.jpg (123851 bytes)

1. Draw the life cycle of a fern. Your drawing should contain the following terms:

2N, N, sporophyte, sorus, sporangium, meiosis, spores, gametophyte, antheridium, sperm, archegonium, egg, fertilization

2. Observe sori on the underside of a fern leaf using a dissecting microscope. Are sporangia visible? Indicate where this structure occurs in the life cycle diagram that you prepared (above). 

Fern showing sori on
underside of leaf		 fern sporangia.jpg (47544 bytes)
Fern sorus x40 Image1.jpg (58225 bytes)

3. View a slide of a fern gametophyte showing antheridia. Find the antheridia. What are produced in these structures? Indicate where this structure occurs in the life cycle diagram that you prepared (above). 

Fern prothallium (gametophyte)
showing antheridia x40		 img013.jpg (104097 bytes)

4. View a slide of a fern gametophyte showing archegonia. Find the archegonia. What are produced in these structures? Indicate where this structure occurs in the life cycle diagram that you prepared (above). 

Fern prothallium (gametophyte)
showing archegonia x40		 img014.jpg (115355 bytes)

5. View a slide of a fern gametophyte containing zygotes. What generation is represented by these zygotes?

Fern prothallium (gametophyte) fertilization img015.jpg (65023 bytes)

Horsetails

Horsetails img016.jpg (102735 bytes)

1. Observe a live horsetail. Find the a strobilus. What reproductive structures are contained within the strobilus?

Horsetail showing strobilus img017.jpg (34971 bytes)

Phylum: Lycophyta

Members of this phylum have horizontal stems, upright stems, and small, spike-shaped leaves called microphylls.

Club Mosses

1. Observe a specimen of live club mosses such as Lycopodium. Find rhizomes. Do the specimens have any strobili? (Be sure to look up these words if you do not understand them.)

Club moss (lycopodium)  img018.jpg (120583 bytes)

Spike Mosses

1. Obeserve a specimen of a spike moss such as Selaginella.

Spike moss (selaginella)  img019.jpg (105606 bytes)

Review Questions

Do the lecture review questions on seedless plants. The first time you go through the questions, you will probably need to look up the answers. Keep going through them until you do not need to look up the answers.

Click here to open the answer sheet for printing.

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