Question

Use your knowledge of genetics to complete the worksheet.
1. In humans, there are 4 types of blood: type A, type B, type AB and type O.
The alleles A and B are codominant to each other and the O allele is
recessive to both A and B alleles. A person with type A blood will have either
AA or AO genotype.
What are the possible genotypes that will produce type B blood?
What is the possible genotype that will produce type O blood?
What is the possible genotype that will produce type AB blood?

Answer 1

The possible genotypes that will produce type B blood are BO and BB alleles.

The possible genotype that will produce type O blood AO and BO.

The possible genotype that will produce type AB blood AO and BO or AA and BB alleles.

Explanation:

We know that one allele from either parent determines the trait in offspring. Each parent donates one of the alleles from ABO blood group alleles.

Possible genotype that produces type B blood is BB or BO.

From the punnet square, the parent having BB or BO genotype will produce B type blood.

     B     O

B   BB  BO    

B   BB   BO    B type blood.

   

A and B alleles are dominant over O allele.

Those having genotype OO will have Type O blood. The parent having genotype AO and BO can produce child with O blood type.

    A     O

B  AB  BO

0 AO   OO          25% progeny will have O type blood.

The person having AB type blood will not produce progeny of blood type O.

Possible genotype for AB blood type is AB

A person with genotype AO and person with genotype BO could produce

   A    O

B  AB  BO

O  AO OO   25% chances of AB will have antigen for type and type B