How is a moss different than a fern?
The dominant form for the moss is the gametophyte. For the fern it is the sporophyte. Both experience both, with an alternation of generations. Both have gametophyte generations that produce gametes from archegonia and antheridia which swim together and form a diploid zygote that develops by mitosos into a mature spore-formin sporophyte. But in the ferns, this is the plant form that you see and think of when you think of a fern, complete with fronds. In the moss, this sporophyte phase is a non-photosynthesizing, parasitic, epiphytic shoot growing out of the plant that you normally think of as the moss.
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