Question

The alleles for human blood types A and B are co-dominant but both are dominant over the type O allele. The Rh factor is separate from the ABO blood group and is located on a separate chromosome. The Rh-positive allele is dominant over Rh-negative. Indicate the possible phenotypes from the mating of a woman with type O Rh-negative with man with type A Rh-positive?

Answer 1

We can obtain a prediction of the children's blood using the method of punnet squares, like a game of tic-tac-toe. We first give use the assumptions that the woman with type O is OO and the man is AO, since A is dominant. With the first punnet squares, there will be a 50-50 percent chance that the child could be AO or OO. 

Now for the Rh negative and positive, we still use the punnet squares as basis for prediction and tying them together to form independent segregation. 

The end result would be a child having type A with either Rh positive or Rh negative and a child with type O and having either Rh positive or Rh negative.