Two parents with normal vision have two sons, one color deficient and one with normal vision. If this couple then has six daughters, can you predict what percentage of the daughters will have normal color vision?
A) 75%
B) 100%
C) 25%
D) 0%
E) 50%

Question

Quizplus · Accepted Answer

Color blindness is a sex-linked recessive trait carried on the X chromosome. Since the mother must be a carrier (XcX) for the son to be color deficient, and the father has normal vision (XY), all daughters will inherit one normal X from the father and either a normal or carrier X from the mother, resulting in normal vision.

Two Parents with Normal Vision Have Two Sons, One Color