A certain species of fish has alleles for red scales and for blue scales.Mating a red-scaled fish to a blue-scaled fish yields fish with a patchwork of red and blue scales.Mating one of these patchwork fish to a blue-scaled fish yields half patchwork and half blue-scaled fish.What can you conclude about the red and blue alleles?
A) The blue allele is dominant.
B) The red allele is dominant.
C) The red and blue alleles show incomplete dominance.
D) The red and blue alleles are codominant.
E) The alleles are pleiotropic.

Question

Quizplus · Accepted Answer

The fact that both red and blue alleles are expressed in the patchwork fish suggests that they are codominant. This means that when both alleles are present, they are both expressed equally in the phenotype. The half patchwork and half blue-scaled fish from the second mating also supports this idea, as it indicates that the patchwork allele and the blue allele have equal chances of being inherited. None of the other answer choices are supported by the information given.

A Certain Species of Fish Has Alleles for Red Scales