Mosses & Ferns Lab

ferns are not better-equipped for life on land than mosses

false

This stage of your moss plant is... a complex plant or a simple plant?

simple plant

Ferns do not have well-developed vascular tissue in their roots, so they don't thrive as well in very dry environments

true

Protonema

The early stage of growth from the spore

Therefore, is it haploid or diploid?

diploid

The ___________ sporophyte grows from the union of an egg and sperm. In plants the sporophyte performs ________ to make ________.

diploid meiosis spores

That gametophyte in ferns is called the ...

fern prothallium

Haploid

(genetics) an organism or cell having only one complete set of chromosomes

Diploid

(genetics) an organism or cell having two sets of chromosomes or twice the haploid number

Sporophyte

-Diploid, or spore-producing, phase of an organism -The sporophyte produces spores which grow into new gametophytes. (It means spore plant)

Gametophyte

-Haploid, or gamete-producing, phase of an organism -The gametophyte produces gametes which fuse (fertilization) to start the next generation called the sporophyte (It means gamete plant)

How many sets of chromosomes does a sperm have?

1

How many sets of chromosomes does an egg have?

1

Botanist theory on moss

Botanists tell us that the mosses developed from evolutionary changes in the growing spore of an algae. If this is true, and land traits were incrementally added to the algae gametophyte producing what we see today as a moss gametophyte. A logical implication of this theory is that the early growing moss spore should show some ancestral resemblance to the algae

moss archegonia

Female Female organs usually have one large egg cell in the middle of a vase-like or bowling-pin-shaped structure.

Alternation of generations

It allows plants to reproduce by using two different methods - spores and gametes.

Why do they have a reproductive and a "survival" function?

It is reproductive in function because many thousands of them can be made, and each can grow into it a new gametophyte moss plant. Also, these spores are very tough and can easily survive through the dry part of the year. They will germinate when the environmental conditions get better.

fern prothallium

It is very small compared to the sporophyte and does not live long because its only purpose is to make eggs and sperm. Those eggs and sperm unite to produce the next sporophyte generation plant. In class, we would depend on slides or preserved specimens to examine the prothallium and the fern sex organs. In online class, we'll look at pictures of those specimens.

What does the Vascular tissue do?

It moves food and water up and down the plant through specialized tubes.

moss antheridia

Male Male organs are usually round or oval in shape and have a dozen or more small round cells inside called sperm. After a rain the moss sperm must swim to the egg for fertilization. This means that moss reproduction depends on a wet environment.

Decide: Is the fern plant simple or complex (compared to mosses)?

More complex

What are the little round balls inside the capsule?

Sporophytes (diploid cells)

Which stage in the life cycle of algae produces eggs and sperm?

Stage 1 (gametophyte)

What is that Funny-Looking Stalk?

The stalk with its capsule is actually the next generation stage in the life cycle of the moss

Vascular tissue of plants is like the ______________ in animals.

circulatory system

The vascular tubes may be grouped in _________ that show a cylinder or a horseshoe-shaped arrangement in the ___________ of the stem

clusters cross-section

The fern plant that you normally see is... Simple or complex? Haploid or diploid? Gametophyte or sporophyte?

complex diploid sporophyte

Which means that this stage of your moss plant produces... gametes (eggs and sperm) or spores?

gametes

In early land plants like the mosses and ferns, the gametophyte is a small plant that produces _________ (eggs and sperm), and the gametophyte is already ________ when it does so.

gametes haploid

This means that you are looking at the... sporophyte generation or gametophyte generation?

gametophyte generation

What do these structures grow into?

gametophytes

Therefore, this stage of the moss plant is probably... haploid or diploid?

haploid

Do moss plants have vascular tissue?

no

The spore is both a ________________________ part of the moss life cycle.

reproductive and a "survival"

Finally, what will is produce in this stage (spores or gametes)?

spores

What are the small balls called?

spores

What will the spores grow into?

spores will grow into the next gametophyte generation

Now conclude: Which generation is the fern plant (gametophyte or sporophyte)?

sporophyte

The fertilized egg will grow into a... gametophyte plant or sporophyte plant?

sporophyte plant

Now that you know what the little balls are, you also know that the "funny looking stalk" is actually the... gametophyte stage or sporophyte stage?

sporophyte stage

When the egg and sperm unite, we are back to... one set of chromosomes or two sets of chromosomes?

two sets of chromosomes

Where are the small "packets" of fern spores usually found?

underside of the fern plant leaves