Lab 2 Seedless Vascular Plants Flashcards
When we are looking at the fronds (leaves) of the Boston fern we notice newer leaves called _________ that are unrolling from horizontal underground stems.
Fiddleheads
What is the name for the whole leaf on a Boston fern?
They are called the fronds
What is a fond pinna?
This is a single leaflet from the larger fond.
What are rhizomes?
They are the horizontal, underground, specialized stems that serve as the main growth axis for a developing sporophyte
What is the genetic state of the fronds, fiddleheads and rhizomes as well as the entire sporophyte?
Diploid
What are the veins of the pinna made of in the boston fern?
They are made of
1) Xylem
2) Phloem
What about the female gametophyte on which the newly growing sporophyte depends on?
Does it physically separate?
That is haploid and is genetically distinct from the sporophyte.
It will once the sporophyte has grown some.
In the pinna that we took from the frond, identify:
- Stomates (stoma)
- Epidermal cells
Okay
What is a sporangium?
They are the spore holding apparatuses that are present on the leaflets of pinnae.
What are sporangia?
These are multiple sporangium.
What is a sorus?
This is a collection of multiple sporangia.
What are sori?
These are collections of multiple distinct groups of sporangia.
What is the function of the annulus?
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.
What was the acetone supposed to do if we had fresh sporangia?
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.
Understand the picture of the scraped sporogonium from the fern, and identify:
- Sporangium
- Annulus (really can’t see)
- Spores that are spilled all over
Okay
What is the fern prothallus?
A fern that is monoecious
Look over the prothallus picture and slide and identify:
- Antheridia
- Archegonia
- Rhizoids
Okay
What are Rhizoids?
They are the noodle looking appendages that exist both on the antheridia and the archegonia
SEE PHOTO
Look the fern sorus cross-section and identify:
- Sporangium
- Annulus
- Spores
- Pinna
Okay
Is a mature spore haploid or diploid?
Haploid
Look at the fern prothallus (gametophyte) with a developing sporophyte and identify:
- Each structure
- Genetic state of each structure
Okay
Look at the plastic mount of psilotum.
Know how to spell this and what it is.
Okay
Look at a Psilotum stem cross-section and identify:
- Stomates
- Guard cells
- Stele
- Epidermis
- Cuticle
Okay
What is the stele?
Why would we expect this in the lab today?
It is the central vascular tissue of the stem.
Because we are learning about seedless vascular plants.
What waxy structure is on the outer surface of the epidermis?
Cuticle
What is the function of the cuticle?
To prevent water loss
Be able to identify the Equisetum.
Okay
What is the reason that the Equisetum is sometimes called the scouring rush?
- Cell walls are filled with silica
- Used historically to clean stuff
What is the advantage of ferns having the antheridia and the archegonia on the lower surface of the prothallus (gametophyte)?
- The lower part of the prothallus is usually in contact with the moise substrate so they don’t dry out
- Sperm have optimum conditions for movement
Why are seedless vascular plants allowed to be so big compared to bryophytes?
Because they can transport their nutrients and prevent carbon dioxide from escaping.
What are two characteristics of the seedless vascular plants that allow them to survive in drier habitats than bryophytes?
- They can regulate their stomata to prevent loss of nutrients
- They have thicker cell walls that contain lignin that can help to prevent water loss
How is the life cycle of bryophytes and seedless vascular plants similar?
They both alternate generations
They can both be monoecious or dioecious
They both produce spores
How is the life cycle of seedless vascular plants different to bryophytes?
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
What type of weather conditions will facilitate spore dispersion?
Dry and windy conditions.
