Why are blood cells so far apart, while skin cells are grouped closely together

In natural selection, what is actually “selected? ” a) alleles are directly selected b) genotypes are directly selected c) phenotypes are directly selected d) entire populations are directly selected

Rue or false siblings look simila rbecause they each have some traits of their parents.

If a strand of dna has 35% thymine. what is the percentage of cytosine, adenine, guanine?