Anonymous A. answered • 03/23/22
Biology Graduate Teaching Assistant
To answer your questions:
Compare and contrast between seed plants and seedless plants:
There is a lot of information you could put here. Seedless plants are plants such as bryophytes (these are nonvascular plants such as mosses) and polypodiophytes (such as ferns). Seed plants include Gymnosperms (non-flowering seed plants such as conifers) and Angiosperms (all flowering plants).
Dominant generation:
The dominant generation is referring to which generation in the alternation of generations life cycle is the one that organism spends most of its time as. The only group of plants that is gametophyte dominant is Bryophyta (an example being mosses). All other plants are sporophyte dominant. This means that when you look at moss, generally you are looking at the haploid gametophyte generation.
Gametes require water:
Seedless plants are restricted to moist habitats primarily because their gametes still require water. The sperm is still flagellated and needs water in order to swim to the egg.
Alternation of generations:
Alternation of generations is the life cycle that all plants follow. Plants alternate between a diploid sporophyte stage and a haploid gametophyte stage. This is best illustrated by looking at a diagram where you'll be able to see that the sporophyte stage produces what is called a sporangium that produces and releases haploid spores through the process of meiosis. The spores develop into the gametophyte which produces haploid gametes: egg and sperm. The gametes come together during fertilization. The fertilized gametes create a diploid zygote. This will now develop into a sporophyte, and the cycle repeats.
Long-distance of dispersal:
This answer really depends on the plant, but generally, the seedless plants don't disperse as well because they still need water for their gametes as I stated above. Gymnosperms generally use wind dispersal, and Angiosperms employ a number of methods of dispersal including wind, animals, water, etc.
