AP BIOLOGY

HEREDITY

MULTIPLE ALLELES

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
If a person has type B blood, the phenotype is B. What can the genotype be?
A
IBIB or IBi
B
IAIA or IAi
C
IAIB
D
ii
Explanation: 

Detailed explanation-1: -Genotypes BB and BO have Type B Blood Genotypes BB and BO refer to individuals having either two “B” alleles for blood type, or one “B” allele and one “O” allele. Both of those genotypes results in having Type B blood. The BO genotype results in Type B blood because B is dominant over O.

Detailed explanation-2: -The human ABO blood group is controlled by a single autosomal gene with three alleles, IA, IB and i. Individuals with either the IAIA or IAi genotypes have blood type A. Those with IBIB or IBi have blood type B. Those with IAIB have blood type AB, and those with ii have blood type O.

Detailed explanation-3: -In order for a person to have type B blood, their genotype must be either BB or BO. A person must have inherited a B allele from at least one parent. They cannot have inherited an A allele from either parent.

Detailed explanation-4: -IA, IB both are dominant forms so, person with ii allele have O blood group. Thus people with IAIA or IA i have blood group A and individuals having IBIB or IB i genotype have B blood group. Whereas person having genotype IAIB show phenotype AB and individuals with genotype ii have phenotype O [2].

There is 1 question to complete.