Question

mary has type a blood. her son bill has type ab blood. which blood type does bills dad have if he is homozygous for blood type?
a
b
ab
o

Explanation:

Blood type is determined by alleles. Mary has type A blood (genotype \(I^AI^A\) or \(I^Ai\)). Bill has type AB blood (\(I^AI^B\)). Since Bill's dad is homozygous, and Bill has \(I^B\) allele (from dad as Mary can only give \(I^A\) or \(i\)). Homozygous for blood type, so dad's genotype is \(I^BI^B\) (type B).

Answer:

B.