Lab 1 Byrophytes Flashcards
What is the mature sporophyte (diploid) connected to?
It is connected both physically and nutritionally to the female gametophyte via the foot which is embedded in the female tissue.
What is the role of the operculum in the life cycle of mosses?
It is the structure that controls the mechanism of releasing the spores from the capsule (sporangium)
It also helps protect the developing spores and acts kind of like a lid
What is the seta of the mature sporophyte?
It is the stalk extending from the foot of the sporophyte which elevates the capsule (sporangium)
What is the type of nuclear division that is involved in the development of the sporophyte plant from a zygote?
Mitosis
What type of nuclear division is involved in producing the gametes that will fuse to form a sporophyte?
Mitosis
What is the type of nuclear division that is involved with development of haploid spores within the capsule (sporangium)?
Meiosis
What do the male spores develop into?
What is the development involve?
They develop into male gametophytes.
Involves development from protonemata to bud and then gametophytes
What is the specialized tissue of the male gametophytes that is responsible for producing sperm?
anteridium
Look at the picture of the “Mnium” antheridia and identify the spermatogenous tissue.
Ok
What do the female spores develop into?
They develop into female gametophytes
What is the gametophore of gametophytes?
It is the part of the haploid plant that where the various sex organs develop
What is the specialized tissue of the female gametophyte that is responsible for producing eggs?
archegonium
Look at the picture of “Mnium” archegonia and identify the location of the egg.
Okay
How does the process of fertilization work?
When there is water, the antheridia will release sperm that allows the sperm to contact the egg within the archegonium
What is the function of the spores?
They have a variety of purposes, but the main ones are for reproduction, long-range dispersion, protection, and genetic diversity.
Do gametophytes have vasculature?
No they do not have any vasculature; there are no distinct veins in their appendages.
On the demo slide “Polytricum” moss leaf-like gametophyte, is there an apparent mechanism to regulate gasses in an out of the plant?
No it does not.
What are the genetic states of the leafy plant and the seta/sporangium (capsule)?
The leafy plant is the gametophyte (haploid)
The seta and sporangium (capsule) are diploid
What does the term monoecious mean?
It means that the male and female sex cell producing organs are located on the same plant.
What does the term dioecious mean?
It means that the male and female sex cell producing organs are located on different plants.
What structure right after fertilization of the female gametophyte, is found where we see the base of the seta in the sporophyte portion of the plant?
Archegonium
The place that houses the egg in the female gametophyte
What is the function of the sporangium?
- It produces haploid spores
- It facilitates release of spores
- It protects developing spores
- Regulates the dispersion
What is the function of the seta of the sporophyte?
- Elongate the capsule (better dispersion)
- Transfer nutrients to the capsule
- Physically supports the capsule
What is the genetic state of the spores?
Haploid
What is responsible for actually creating the spores within the sporangium?
The spore mother cells.
What is the genetic state of the operculum?
diploid
What is meant by “alternation of generations”?
in the life cycle of the plant there are two distinct generations that alternate between genetic states (haploid and diploid)
What is a zygote and at what point in the life cycle of bryophytes is this structure formed?
Zygote refers to when the haploid sperm from the male gametophyte fertilizes the haploid egg from the female gametophyte.
The zygote forms after fertilization which occurs shortly after the release of the sperm from the male gametophyte
An embryo develops from a zygote.
What develops from an embryo in the bryophytes?
The sporophyte generation
What micro-climate conditions are required for fertilization?
- Wet (high humidity)
- Cool to moderate temps
(don’t want it to dry out) - Shade
What micro-climate conditions are required for spore release?
- Dry (no humidity)
- Moderate to warm temps
- Windy
All has to do with efficacy of dispersal
What environment does the typical bryophyte live in?
Shady, moist areas with stable moisture, humidity and low light.
What three things are bryophytes?
- Mosses
- Liverworts
- Hornworts
