Question

Mr. jones has blood type b and mrs. jones has blood type ab. what is the probability that they will have a child with blood type a if both of mr. jones’s parents were ab?
a. 0%.
b. 25%.
c. 50%.
d. 100%.

Answer 1

Cross: Ib Ib  ×  Ia Ib

Offspring: IaIb , IbIb, IaIb, IbIb

ab = 50%
b = 50%
a = 0%

In short, Your Answer would be Option A) 0%

Hope this helps!

Answer 2

Answer:

The correct answer would be a. 0%

Mr. Jones has blood group B and that of their parents was AB. Thus, he must be homozygous for blood group B that is, $I^{B}I^{B}$.

Then, he would only produce one type of gamete, $I^{B}$.

The blood group of Mrs. Jones is AB. Thus, the genotype of her gene would be $I^{A}I^{B}$.

Hence, she would produce two types of gametes, one containing $I^{A}$ and other containing $I^{B}$.

The cross would result in the production of children with two types of genotypes $I^{A}I^{B}$ and $I^{B}I^{B}$.

Thus, the phenotype of children can be either blood group AB or blood group B.

Hence, the probability of a child having a blood group A would be 0%.