Answer: 1). A and B are both dominant (because A and B are codominant to one another)
2). E. All of the above
Explanation:
1). From the image above, A and B are both dominant because they are equally expressed when they occur in a pair (when they occur as blood type AB), also they are dominant because each of them expressed itself when it occurs in a pair with a recessive allele (IAi and IBi).
2). The children of a father with A blood and a mother with B blood will have all the four blood types: A, B, AB, and O. If each parent has a recessive allele, that is if each parent is heterozygous for his/her blood type (IAi for the father and IBi for the mother), the cross between them will produce all the four possible blood types.
See the attached punnet square for more information.
