Blonde hair (b) is recessive, and brown hair (B) is dominant. A parent has brown hair (Bb). Their first child has blonde hair (bb). Their second child has brown hair (BB). What must the other parent have (hair color and allele combination)? (1 point) Responses Bb, blonde hair Bb, blonde hair - no response given BB, brown hair BB, brown hair - no response given bb, blonde hair bb, blonde hair - incorrect Bb, brown hair

Answer 1

To determine the allele combination of the other parent, we can analyze the information given:

1. One parent is Bb (brown hair) and can pass either a B (brown hair) or a b (blonde hair) allele.
2. The first child has blond hair (bb), which means they received one recessive b allele from each parent.
3. The second child has brown hair (BB), which means they received a B allele from both parents.

Since the first child is bb, the other parent must contribute a b allele (because the Bb parent can only contribute a B or b). Therefore, the other parent must also have at least one b allele.

Given that the second child is BB, this means the other parent must have contributed a B allele to this child.

The only possible combination for the other parent, given both scenarios, is Bb (brown hair).

So, the other parent must have Bb (brown hair).