Question

If you had a black male guinea pig and brown female guinea pig, but you didn't know which was the dominant characteristic, how would you find out the dominant color, assuming the dominant characteristic is homozygous,?

Answer 1

Options for the question are not given. They are as follows :

A.  Mate them and see what color the offspring are—that will be the dominant color

B.  Mate them and see what color the offspring are—the other will be the dominant color

C.  Mate them, and then mate their offspring to see what color the next generation is

D.  Mate them together, and then mate their offspring to see what color the next generation is—the other color will be the dominant color

Answer:

A.  Mate them and see what color the offspring are—that will be the dominant color

Explanation:

Out of the two colors, one will be recessive and one will be dominant. Recessive color will be homozygous since it is only expressed in homozygous condition. It is also given that in this cross the dominant color is also in homozygous condition.

When the guinea pigs mate, the resulting progeny will obtain one dominant allele from the dominant color parent and one recessive allele from the recessive color parent. The progeny will be heterozygous and show the dominant phenotype since the dominant allele will mask the recessive allele. Thus, the color which is visible in their offspring will be the dominant color.