AP BIOLOGY

HEREDITY

INCOMPLETE DOMINANCE

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
Two parents think their baby was switched at the hospital. The mother has blood type O, the father has blood type AB and the baby has blood type B. Complete a punnett square and then answer the question. What is the mother’s genotype? What is the father’s genotype?
A
Mom genotype is IᴬIᴬ, Dad genotype is IᴬIᴮ
B
Mom genotype is ii, Dad genotype is IᴮIᴮ
C
Mom genotype is ii Dad genotype is IᴬIᴮ
D
Mom genotype is ii Dad genotype is ii
Explanation: 

Detailed explanation-1: -If the father’s blood group is O, he has the genotype IOIO or (ii) . The mother has blood type AB, which means that her genotype would be IAIB. The possible combinations of these two groups would result in children having genotypes IAIO or IBIO, which would give them blood groups A or B respectively.

Detailed explanation-2: -If a father’s blood group is o+ and mothers’s is AB+, what would their children be? The genotype of the father or possible genes he could pass on would be O O; the mother, A B. The genotype of the children would be AO & BO.

Detailed explanation-3: -Two parents with A blood type can produce a child with either A or O blood types. Two parents with B blood type can produce a child with either B or O blood type. One parent with A and another with B can produce a child with A, B, AB or O blood types.

Detailed explanation-4: -In most cases, an O parent and an AB parent will have only A or B kids. I added a table at the end of this answer that has all blood type combinations for two parents plus the possible blood types for their children. Exceptions to these rules are extremely rare.

There is 1 question to complete.