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

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%.