What key adaptations do vascular seedless plants have which

What key adaptations do vascular, seedless plants have which allow them to be successful in areas which bryophytes may not be? How are club mosses, whisk ferns and horsetails different from ferns? What does \"alteration of generations\" mean?

Solution

5. bryophytes lack lignified water conducting tissue as non seeded vascular plants have to conduct water upwards for growth and reproduction .

6. club mosses,whisk fern and horsetails are small vascular plants intermediate(some characters matches with bryophytes) ferns are fully developed plants.

7.  the occurrence of two or more forms differently produced in the life cycle of a plant or animal usually involving the regular alternation of a sexual with an asexual generation but not infrequently consisting of alternation of a dioecious generation with one or more parthenogenetic generations. for example bryophytes have the gametophyte in the dominat generation, rather than the sporophyte (which is the dominant generation in ferns).