Major Groups of Land Plants and Reproduction Flashcards
What arose independently in evolution many times? (in land plants)
alternation of generations
What are the generations of alternation of generations?
gametophyte (haploid, n)
sporophyte (diploid, 2n)
both are multicellular
What is the difference between alternation of generations and the regular process?
the haploid stage is unicellular not multicellular
what is the zygote produced by fertilization called?
sporophyte
what does a delay in the meiosis process for mitosis result in?
alternation of generations
What do gametophytes make?
gametes
what do sporophytes make?
spores
what process do sporophytes go thorugh to make spores? why?
meiosis because sporophytes are diploid
what process do gametophytes go through to make gametes, eggs and sperm? Why?
mitosis because gametophytes are haploid
What are the 4 out of the 10 divisions of land plants that we are going to focus on?
The mosses
The conifers
The ferns
The angiosperms
What division(s) of land plant has no vascular tissue?What does this result in?
the mosses, result in very thin, low growing plants,
What is the vascular system?
the xylem and the phloem
How do moss move water across itself, great distances, when it doesn’t have a vascular system?
The moss are so thin that no cell is very far from the moist surface level of the moss
how low growing are the mosses?
never taller than a few centimeters
do moss have leaves? why or why not?
no they don’t because they lack true vascular tissue
what is the dominant life cycle in the mosses?
the gametophyte, haploid life cycle
where is the sporophyte located on the plant?
they grow out of the gametophyte
are mosses homosporous or heterosporous and what does that mean?
mosses are homosporous, they only have one size of spore
In mosses, what develops into the multicellular gametophyte?
the spores, some becoming female and some becoming male
on the male side, what happens after the spore germinates?
it makes the male moss plant protonemata, then makes sperm (its gametes) through mitosis with the anthrerida (male jacketed sex organs)
on the female side, what happens with the spore?
the spore divides making a gametophore, and developes into a gametophyte. The female jacket sex organs, archegonia, make an egg through mitosis
How does fertilisation happen with moss?
drops of rain pick up the sperm made by anthrerida and lands on the female gametophyte where the egg is fertilized.
What si the fertiliszed egg called (moss?
zygote, the new sporophyte
What generation is the sporophyte
the new diploid generation?