A woman who has blood type A positive has a daughter who is type O positive and a son who is type B negative.Rh positive is a trait that shows simple dominance over Rh negative and is designated by the alleles R and r,respectively.Which of the following is a possible genotype for the son?

Question

Quizplus · Accepted Answer

We know that the mother is type A positive (AA or AO) and her son is type B negative (BB or BO). The daughter is type O positive, which means she must have inherited an O allele from her mother and a positive allele from her father. Since the son is Rh negative, we know he must have inherited a negative allele from his father. Therefore, the son's possible genotypes are either BO or BB for blood type and rr for Rh factor. Choice D (I^Bi) represents the possible genotype for the son. The son inherits a B allele from his father and an O allele from his mother, and he is Rh negative (rr).

A Woman Who Has Blood Type a Positive Has a Daughter