A man with blood type B (BB) is married to a woman with blood type O. Show the genetic cross. What percentage of their children will have: A) A blood B) B blood C) O blood D) AB blood

In genetics, blood types are determined by specific alleles inherited from our parents. In this case, we are examining the inheritance of blood types from a man with blood type B (genotype BB) and a woman with blood type O (genotype OO).
To determine the possible blood types of their children, we need to perform a genetic cross. Here's how the cross works:
Parent Genotypes:

Father: BB (blood type B)
Mother: OO (blood type O)

Possible Allele Combinations for Children:

From father (B): Each child can inherit a 'B'.
From mother (O): Each child can inherit an 'O'.

So, the possible genotype of their offspring is BO.
Phenotype (Blood Type) of Offspring:

BO results in blood type B because the B allele is dominant over the O allele.

Now, let's answer the questions:
A) Percentage with Blood Type A:

None of their children can have blood type A, as no A alleles are present in the genotypes of the parents.

B) Percentage with Blood Type B:

100% of the children will have blood type B, as all offspring will have the genotype BO.

C) Percentage with Blood Type O:

None of their children can have blood type O, as the presence of the B allele will mask the O allele.

D) Percentage with Blood Type AB:

None of the children can have blood type AB because there is no A allele present in either parent's genotype.

In summary:

A) 0%
B) 100%
C) 0%
D) 0%

This demonstrates the dominance of the B allele when combined with an O allele in determining blood type.

Answered by OliviaLunaGracy | 2025-07-21