Speciation occurs during the evolutionary development, or phylogeny, of a species. in which of the following situations can speciation occur?
a.
when a population becomes interbred
b.
when two populations merge to become one population
c.
when two populations are reproductively isolated
d.
when a population becomes extinct

Dna, in the nucleus carries the genetic code for making proteins in ribosomes. in the diagram, b, represents the proteins produced. dna cannot leave the nucleus to carry the genetic information to the ribosome where proteins are produced. how does the genetic code get from the nucleus to the ribosome? what does a represent? now