Blood type is determined through multiple alleles: A, B, O. Alleles A and B are codominant, while allele O is recessive. The following chart shows the genotypes as they correspond to blood type.

Reese’s blood type is heterozygous Type B (IBi). Lucy’s blood type is homozygous Type A
(IAIA). What would be the probability that Reese and Lucy would have a daughter that is Type A?

50% chance of having blood type A

Explanation:

Homozygote is the genotype in which two alleles of a gene are the same for a character, it can be dominant or recessive, heterozygotes are two alleles of a different gene, blood groups are inherited from the father and mother, they are found in genes that have three alleles that are A, B, i, where A and B are dominant and allele i, which corresponds to O, is recessive. People who inherit the AA or Ai alleles (AO) have blood groups A (phenotype A), those who inherit BB or Bi (BO) will be from group B (phenotype B), and those who inherit the ii alleles (OO) are of the group O (phenotype O), with the dominant trait prevailing over the recessive in the case that occurs, obtaining a 50% probability of having the dominant character of mother A.

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