Seedless Plants (Kingdom: Plantae)

Bryophytes

The following sections in the class lecture notes on seedless plants will be helpful as you do this laboratory exercise:

Introduction
Alternation of Generations
Classification

Phylum: Bryophyta (Mosses)

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

1. Observe different kinds of moss on display and note the body form of the gametopyyte.

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

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

3. 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

4. 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). 

5. What is produced in this structure (the antheridium)?

6. 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 headMnium antheridial head 40X.jpg (660893 bytes)
Mnium (a moss) antheridial head x40img006.jpg (109676 bytes)
Mnium (a moss) antheridial aead x100img007.jpg (97454 bytes)

7. 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). 

8. What is produced in this structure?

9. 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 x40moss archegonial head X 40.jpg (102370 bytes)
Moss archegonial head x100moss archegonial head X 100.jpg (108610 bytes)

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

Image3.jpg (99407 bytes)

11.Use a dissecting microscope to view a longitudinal section (cut lengthwise).

12. What is produced within this structure (the capsule)?

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 sporesmoss capsule.jpg (17691 bytes)    moss_capsule_1.jpg (21170 bytes)
Moss capsule x40img003.jpg (103205 bytes)

14. How are moss spores dispersed to new locations?

Phylum: Hepatophyta (Liverworts)

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

Marchantia (live)img010.jpg (100485 bytes)

Seedless Vascular Plants

Phylum: Pterophyta

Ferns

Fern gametophyteferns.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. 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
Enlarge the image to v iew the sporangia.
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 these structures (gametophyte and antheridia) occur in the life cycle diagram that you prepared. 

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 these structurs (gametophyte and archegonia) occur in the life cycle diagram that you prepared (above). 

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

Horsetails

Horsetailsimg016.jpg (102735 bytes)

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

Horsetail showing strobilusimg017.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. Identify microphylls. Do the specimens have any strobili? (Be sure to look up these words if you do not understand them.)

Club moss (lycopodiumimg018.jpg (120583 bytes)

Spike Mosses

1. Obeserve a specimen of a spike moss such as Selaginella. Note the structure of the microphylls.

Spike moss (selaginellaimg019.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.