Question

If a normal man marries a normal woman whose father was colourblind, what are the chances that their sons and daughters will be colourblind? Colourblindness is a sex-linked trait that affects males more often than females. With the aid of a Punnett square, indicate the genotypes of the parents, and of the offspring, including their chances of being colourblind in the F1 generation.

Answer 1

If woman's father was colorblind, and she was not, she will be a carrier. One of her X chromosomes will have the recessive colorblind gene.

http://anthro.palomar.edu/mendel/mendel_2.htm