Question

a man who is normal for colour vision marries a normal heterozygous women the chance of their son being colorblind is​

Answer 1

Answer:

That is there is a chance of 1 in 2 (50% or 0.5) of her son being colour blind.

Explanation:

Answer 2

Colour blindness is a X-linked recessive disorder. One copy of the affected gene in males in each cell is sufficient to cause the disorder (X

c

Y). Females with two copies of the affected gene show the disorder (X

c

X

c

). Females heterozygous (X

c

X) for this trait be normal but serve as a carrier of the disease. According to the question, the female is colour blind (X

c

X

c

) and father is normal (XY). The affected mother will inherit the disease to all sons (X

c

Y). Correct answer is option D.

Parent generation : (X

c

X

c

) x XY

Gametes

(X

c

X

c

) -->

XY X

c

X

c

X X

c

X

carrier girl

X

c

X

carrier girl

Y X

c

Y

colour blind boy X

c

Y

colour blind boy