WAEC Biology 2017 Theory — Question 16

Model answer

Testing each possible father genotype against the mother (BO) to see which can produce an O-blood-type child: If the father is BO: BO x BO gives BB, BO, BO, OO offspring (includes OO). If the father is AO: AO x BO gives AB, AO, BO, OO offspring (includes OO). If the father is OO: OO x BO gives BO, OO, BO, OO offspring (includes OO). Since all of BO, AO and OO can father a child of blood type O with a mother of blood type B (BO), the likely blood types of the father are BO, AO and OO.