How many alleles are there for the four main types of human blood?
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19. scientists use meteorites that hit earth to provide evidence of the composition of earth's interior because they hypothesize that

The image shows the evolution of a species of fish. a few fish from a population developed different social behaviors and evolved into different species. two fish according to the image, the fish underwent . the new species of fish had mating seasons that were different from that of the original fish. because of the differences in mating seasons, the fish underwent reproductive isolation. this mode of isolation would be .

Nucleic acids offer variability because they contain alternate forms of genes called .