A Jamaican couple is expecting their first child. The father has blood group AB and the mother has blood group O. Which blood group is NOT possible for their child?

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Question

A Jamaican couple is expecting their first child. The father has blood group AB and the mother has blood group O. Which blood group is NOT possible for their child?

Accepted Answer

AB — Award 1 mark for identifying that AB is not possible. The father (AB) can pass either I^A or I^B allele. The mother (O) can only pass i allele. Possible offspring genotypes are I^A i (group A) or I^B i (group B). A is incorrect — group A is possible (I^A i). B is incorrect — group B is possible (I^B i). D is incorrect — group O requires ii genotype which cannot occur as father must pass either I^A or I^B.

Answer

O

Answer

A

Answer

B

Answer

AB

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