How does crossing over add to the genetic diversity of sexually reproducing organisms?

How are the reproductive cycles of a fungus and a pteridophyte similar? a)both organisms form fruiting bodies that produce diploid seeds. b)both organisms produce haploid spores and exhibit diploid and haploid stages. c)both organisms reproduce sexually when two haploid hyphae fuse. d)both organisms exhibit a diploid stage and are only able to reproduce asexually.

Explain what a zygote is. use the terms egg cell, sperm cell, and fertilization in your explanation.

Up to what percentage of the world's flora consisted of cycads during the triassic period? 100% 75% 50% 20%