Question

In gene of colour blindness contains what number of chromosomes

Answer 1

The person with genotype AaBb can produce four types of gametes and these are: AB, Ab, aB, ab. Since, the person is also suffering from the colour blindness that is an X - linked disorder, so half of the gametes will have X linked gene for colour blindness and half will have normal Y chromosome. Since, only one among the four has genotype of ab.
Hence the probability of gametes which contain abc will be 1/4 = 25%.