question_answer

A normal woman, whose father was colourblind is married to a normal man. The sons would be

A)  75% colourblind              

B)  50% colourblind

C)  all normal                          

D)  All colourblind

Correct Answer: B

Solution :

In fact the woman with normal vision is carrier because her father is colourblind (daughter of colourblind father are either colourblind or carrier) and when she marries a normal man, than the genotype of parents are Carrier woman           Normal man (Carrier  (Colour (Normal (Normal daughter) blind son) daughter)   son) Therefore, 50% sons would be colourblind and 50% would be normal.