Lab 2 Seedless Vascular Plants

Question 1

When we are looking at the fronds (leaves) of the Boston fern we notice newer leaves called _________ that are unrolling from horizontal underground stems.

Answer 1

Fiddleheads

Question 2

What is the name for the whole leaf on a Boston fern?

Answer 2

They are called the fronds

Question 3

What is a fond pinna?

Answer 3

This is a single leaflet from the larger fond.

Question 4

What are rhizomes?

Answer 4

They are the horizontal, underground, specialized stems that serve as the main growth axis for a developing sporophyte

Question 5

What is the genetic state of the fronds, fiddleheads and rhizomes as well as the entire sporophyte?

Answer 5

Diploid

Question 6

What are the veins of the pinna made of in the boston fern?

Answer 6

They are made of
1) Xylem
2) Phloem

Question 7

What about the female gametophyte on which the newly growing sporophyte depends on?

Does it physically separate?

Answer 7

That is haploid and is genetically distinct from the sporophyte.

It will once the sporophyte has grown some.

Question 8

In the pinna that we took from the frond, identify:

1. Stomates (stoma)
2. Epidermal cells

Answer 8

Okay

Question 9

What is a sporangium?

Answer 9

They are the spore holding apparatuses that are present on the leaflets of pinnae.

Question 10

What are sporangia?

Answer 10

These are multiple sporangium.

Question 11

What is a sorus?

Answer 11

This is a collection of multiple sporangia.

Question 12

What are sori?

Answer 12

These are collections of multiple distinct groups of sporangia.

Question 13

What is the function of the annulus?

Answer 13

Its primary function is in spore dispersal.

The mechanism of action is the cells of the annulus will incrementally lose water until the pressure of the cells is so high that the annulus eventually breaks open forcefully, sending the spores flying away to avoid competition.

Question 14

What was the acetone supposed to do if we had fresh sporangia?

Answer 14

It is a polar solvent that is supposed to act as a dehydrating agent that can cause the cells that support the sporogonium to burst, releasing the spores.

Question 15

Understand the picture of the scraped sporogonium from the fern, and identify:

1. Sporangium
2. Annulus (really can’t see)
3. Spores that are spilled all over

Answer 15

Okay

Question 16

What is the fern prothallus?

Answer 16

A fern that is monoecious

Question 17

Look over the prothallus picture and slide and identify:

1. Antheridia
2. Archegonia
3. Rhizoids

Answer 17

Okay

Question 18

What are Rhizoids?

Answer 18

They are the noodle looking appendages that exist both on the antheridia and the archegonia

SEE PHOTO

Question 19

Look the fern sorus cross-section and identify:

1. Sporangium
2. Annulus
3. Spores
4. Pinna

Answer 19

Okay

Question 20

Is a mature spore haploid or diploid?

Answer 20

Haploid

Question 21

Look at the fern prothallus (gametophyte) with a developing sporophyte and identify:

1. Each structure
2. Genetic state of each structure

Answer 21

Okay

Question 22

Look at the plastic mount of psilotum.

Know how to spell this and what it is.

Answer 22

Okay

Question 23

Look at a Psilotum stem cross-section and identify:

1. Stomates
2. Guard cells
3. Stele
4. Epidermis
5. Cuticle

Answer 23

Okay

Question 24

What is the stele?

Why would we expect this in the lab today?

Answer 24

It is the central vascular tissue of the stem.

Because we are learning about seedless vascular plants.

Question 25

What waxy structure is on the outer surface of the epidermis?

Answer 25

Cuticle

Question 26

What is the function of the cuticle?

Answer 26

To prevent water loss

Question 27

Be able to identify the Equisetum.

Answer 27

Okay

Question 28

What is the reason that the Equisetum is sometimes called the scouring rush?

Answer 28

1. Cell walls are filled with silica 2. Used historically to clean stuff

Question 29

What is the advantage of ferns having the antheridia and the archegonia on the lower surface of the prothallus (gametophyte)?

Answer 29

1. The lower part of the prothallus is usually in contact with the moise substrate so they don't dry out 2. Sperm have optimum conditions for movement

Question 30

Why are seedless vascular plants allowed to be so big compared to bryophytes?

Answer 30

Because they can transport their nutrients and prevent carbon dioxide from escaping.

Question 31

What are two characteristics of the seedless vascular plants that allow them to survive in drier habitats than bryophytes?

Answer 31

1. They can regulate their stomata to prevent loss of nutrients 2. They have thicker cell walls that contain lignin that can help to prevent water loss

Question 32

How is the life cycle of bryophytes and seedless vascular plants similar?

Answer 32

They both alternate generations They can both be monoecious or dioecious They both produce spores

Question 33

How is the life cycle of seedless vascular plants different to bryophytes?

Answer 33

Seedless Vascular - dominant generation is sporophyte -sporophyte is independent, non-reliant on gametophyte -drier climates -can disperse spore further Bryophytes - dominant generation is gametophyte -sporophyte is dependent on gametophyte -only wet climates -disperses spores usually by parent gameotophyte

Question 34

What type of weather conditions will facilitate spore dispersion?

Answer 34

Dry and windy conditions.