Question

A man whose father is a colourblind, marries a woman, who is a daughter of a colourblind mother. The offsprings of this couple will be

• A. All daughter and sons are colourblind.
• B. 50% colourblind and 50% normal sons.
• C. Carrier normal son and colourblind daughter.
• D. Colourblind sons and normal daughters.

Answer 1

The correct option is B 50% colourblind and 50% normal sons.

A man is normal and his father is a colourblind, but here X chromosome is not transmitted from his father. Women is carrier because her mother is colourblind. So, normal man with carrier woman, Hence, your cross is as follows:

(X Y) x (Xc X)

Based on this crossing, from the above given figure we can conclude that there is a 50% chance of producing a son who is colorblind and 50% are normal sons.

So, the correct answer is option B.