Gene problem - red-green blindness?

Question

Red-green color blindness is due to a recessive allele inherited on the X chromosome. In the following mating, give the probability that the son will have the defect.

a. Carrier female X normal male
b. Carrier female X color-blind male
c. Color-blind female X normal male
d. Could any of the above matings produce a color-blind daughter?

Answer 1

A son will inherit his Y chromosome from his father and an X chromosome from his mother, so the phenotype of the son depends solely on the genotype of the mother. With this in mind:

a) 50%
b) 50%
c) 100%

For a daughter to be color blind, she must inherit a defective allele from both parents. Therefore the answer is:

d) b

Answer 2

1/4, 1/2, 3/4, 1/4

Answer 3

Red because theres no bones in icecream!