In the ABO blood system in humans, alleles A and B arecodominant, and both are dominant to the O allele. Give all of thepossible genotypes of a female with A-type and a male with B-typeblood.

If the couple in a. had a child with O-type blood, give theconfirmed genotypes of the parents. What is the probability of sucha couple having a child with AB-blood type?

Why are individuals with blood type O, described as universaldonors?