A man with blue eyes (B/b) and black hair (H/h) marries a woman with black eyes and and brown hair. A year later they have a child. The child has blue eyes and black hair. If black eyes are dominant over blue eyes and black hair is dominant over brown hair, then which of the following options correctly predicts the genotype of child?
It’s given that black eye colour is dominant over blue. So we can assign
B to black and b to blue. Similarly, black hair colour (H) is dominant
over brown (h). Based on this we can represent the cross as follows.
MaleFemalePhenotype:Blue eyes and black hairblack eyes and brown hairGenotype:bbHH/bbHhBbhhGametes:bH bh X Bh bhPossible offsprings:BbHh bbHhBbhh bbhh
As the child has blue eyes and black hair, the only possible option among the
possible offsprings with this combination is bbHh.