What are enzymes, and why are they important to living things?

In the context of the neural impulse, which of the following is true about the depolarization of neuron membranes?

Me with these questions image attached

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.