Lab 3 Gymnosperms Flashcards
What is the stele?
This is the central vascular cylinder of a the plants root or stem.
It contains both xylem and phloem as well as supporting tissues.
In the first picture of a pine leaf cross section, what is the light pink stain that is in the middle?
This is the xylem.
It is lignified.
In the first picture of a pine leaf cross section, what is the tissue that is adjacent to the pink stain that appears in the middle?
This is the phloem.
It is not lignified.
In the first picture of a pine leaf cross section, what are the teal sun-looking things that we see on the outer edge of the leaf?
What about the tissue that is surrounding those structures?
These are the resin ducts.
The mass of the tissue around the resin ducts is called the mesophyll.
In the first picture of the pine leaf cross section, what is the most outer layer of cells called?
What would be on the outside of this outer layer?
This is the epidermis.
This is the cuticle.
Based on the slide of the pine leaf cross section, does it indicate that pines are adapted to wet or dry conditions?
List three points of supporting evidence based on the structure.
Dry conditions.
- Thick cuticle
- Presence of resin ducts
- Thick walled epidermis
- Stomata that exists under the epidermis (seen as indentations in the epidermis)
Why would a pine plant need to be adapted to dry conditions?
Because they must be able to survive the winter.
What is a pine microstrobilus?
This is the male cone or the staminate cone.
In the slide of the microstrobilus (male cone) l.s. what is the core, vertical, dark portion called?
This is called the cone axis.
In the slide of the microstrobilus (male cone) l.s. describe the microsporangium.
This is the compartment that contains the pollen grains (microgametophyte) and is supported by the microsporophyll.
In the slide of the microstrobilus (male cone) l.s what does an individual pollen grain look like?
What is the purpose of the wing-like structures called air-sacs?
It is a central circular structure containing the sperm nuclei.
It also has these “disney” like ears which we call air sacs or wings that allow the pollen grain to float through the air better making it easier to reach the female cone.
How many seeds are generally produced on each cone scale of the female cone?
2
What is the megastrobilus?
This is the female cone or the ovulate cone.
In the slide that shows a portion of the developing female cone, what is the ovule integuments?
This is the outer tissue layer or group of tissue layers.
In the slide that shows a portion of the developing female cone, describe the megagametophyte.
This is the body behind the egg-looking things.
In the slide that shows a portion of the developing female cone, what is the micropyle?
This is the opening in the integument of the ovule where the pollen will enter during pollination.
In the slide that shows a portion of the developing female cone, describe the archegonium.
What is inside the archegonium?
It is the egg-looking thing.
The archegonium houses the egg.
What are the genetic states of the various structures within the megastrobilus?
- Integuments - diploid
- Megagametophyte - haploid
- Micropyle - diploid
- Archegonia - haploid
In the seed that you opened, what is the seed coat?
This is the outer covering.
What is the thing in the most center of the seed?
This is the embryo`
What does the integument become?
This becomes the seed coat.
What does the megagametophyte become?
Nutrient source.
What does the fertilized egg become?
The embryo
Is the megagametophyte energy source stored as lipids or starch?
Lipids
What is wood?
This is secondary xylem.
What kind of xylem cells make up pine wood (and virtually all gymnosperms)?
Tracheid
Looking at the crushed wood of the pine vs the magnolia (gymnosperms versus angiosperms), which one was mainly green and which one was colorful?
The pine was green
The angiosperm was colorful
What is the difference between the gymnosperm wood and the angiosperm wood?
The gymnosperms only have tracheids for the most part and they are not as good at conducting water.
The angiosperms have tracheids, vessel elements, and parenchyma cells.
What is the pith of the stem?
This is the center most portion.
How do we identify the annual rings?
You look at the lines of the secondary xylem.
What does the word gymnosperm mean?
How does pollination differ from gymnosperms to angiosperms?
It means seed
They rely more on wind
