A laboratory mouse homozygous for an RFLP marker is mated to a wild mouse that is heterozygous for that marker.One of the heterozygous individuals resulting from this cross is mated back to the wild parent.What proportion of the offspring will have the same RFLP pattern as the original laboratory mouse?
A)none of the offspring
B)1/4
C)1/2
D)3/4
E)all of the offspring

Question

Quizplus · Accepted Answer

The original laboratory mouse is homozygous for the RFLP marker, so it can only pass on one allele to its offspring. The wild mouse is heterozygous, so each of its offspring has a 50% chance of inheriting the same allele as the original laboratory mouse. When one of the heterozygous offspring is mated back to the wild parent, half of their offspring will inherit the same allele as the original laboratory mouse. Therefore, the proportion of offspring with the same RFLP pattern as the original laboratory mouse is 1/2.

A Laboratory Mouse Homozygous for an RFLP Marker Is Mated