In general, how are the causes of mass extinctions different from the causes of background extinction?

In some plants, pointed leaves (p) are dominant over rounded leaves (p). a plant with a genotype of pp

One of the purposes of transcription is to produce a sequence of bases that

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.