Blood type in humans follows a multiple allele inheritance pattern. There are three alleles for blood type in the human population, and each person only carries two of those three alleles within their genome. One allele is inherited from the father, and the other allele is inherited from the mother. The A-type allele, IA, is codominant with the B-type allele, IB, which are both completely dominant to the recessive O-type allele, i. These alleles combine to create one of four phenotypes, type A blood (either genotype IAi or IAIA), type B blood (either genotype IBi or IBIB), type AB blood (genotype IAIB), and type O blood (genotype ii).
A mother with type A blood has a son with type O blood. Identify the genotype that the father must have in order to produce this child.
(1 point)
Responses
cap i to the cap A th power cap i to the cap b th power
cap i to the cap b th power cap i to the cap b th power
cap i to the cap b th power i
cap i to the cap A th power cap i to the cap A th power
The correct genotype that the father must have in order to produce a son with type O blood is cap i to the cap i power.
explain how this works
In humans, blood type is determined by the presence of certain antigens on the surface of red blood cells. These antigens are determined by the combination of alleles inherited from both parents.
In this case, the mother has type A blood, which means she has at least one copy of the A-type allele (IA) in her genotype. However, since A-type allele (IA) is codominant with the B-type allele (IB), it means she could have inherited two copies of the A-type allele (IAIA) or one copy of the A-type allele and one copy of the O-type allele (IAi).
The son has type O blood, which means he has two copies of the O-type allele (ii) in his genotype.
Since the son has O-type blood, he must have inherited an O-type allele from his mother (either IAi or ii), because the O-type allele is recessive and does not produce any antigens.
Therefore, the father must contribute an O-type allele (i) to the child. The possible genotypes for the father could be either IAi or ii. However, since the child inherits an O-type allele from the mother, the father's genotype must be ii.