AP BIOLOGY

Detailed explanation-1: -Every person has two number 9 chromosomes and, therefore, two alleles for ABO blood types. However, there are three possible alleles-IA, IB, and i (Type O)-that can occur on each number 9 chromosome.

Detailed explanation-2: -The ABO system blood group A – has A antigens on the red blood cells with anti-B antibodies in the plasma. blood group B – has B antigens with anti-A antibodies in the plasma.

Detailed explanation-3: -In incomplete dominance, a mix of the alleles within the genotype is seen within the phenotype. Complete answer: ABO blood group is the best example of Codominance, Incomplete dominance and Dominance. Codominance – an expression of phenotypes of both parents is called codominance.

Detailed explanation-4: -The gene responsible for the ABO blood group system is I. This gene exists in three allelic forms-IA, IB and i. IA and IB are dominant alleles and i is the recessive allele. Since, three alleles for ABO blood group are found in a population, it is an example of multiple allelism.

Detailed explanation-5: -The ABO blood group system is one of the best examples of codominance. There are different types of red blood cells such as A, B, AB and O with or without the Rh factor. The difference is in the antigen present on the red blood cell surface which determines the specific blood group in an organism.