> Blood Typing Problems Answer Key
Blood Type Problems ..KEY

Original File : Blood Type Problems

1. List all the possible genotypes for each of the 4 blood types:

Type O _____OO_______

Type A _____AA, AO_______

Type B _____BB, BO_______

Type AB ___AB_________

SHOW WORK!

2. A man with AB blood is married to a woman with AB blood. What blood types will their children be and in what proportion?

1/4 AA or type A Blood
1/4 BB or type B Blood

1/2 AB

3. A man who has type B blood (genotype: BB) is married to a woman with type O blood. What blood type will their children have?

All will have genotype BB, and be type B Blood

4. A woman with type A blood (genotype: AO) is married to a type B person (genotype: BO). What blood types will their children have?

1/4 will by AB, type AB blood; 1/4 will be AO, or type A Blood; 1/4 will be BO, or type B blood; 1/4 will be OO, type O Blood

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5. A woman with type A blood is claiming that a man with type AB blood is the father of her child, who is also type AB. Could this man be the father? Show the possible crosses; remember the woman can have AO or AA genotypes.

It is possible. The mother can be either AA or AO and still produce a child with type AB blood from that father.

6. A man with type AB blood is married to a woman with type O blood. They have two natural children, and one adopted child. The children's blood types are: A, B, and O. Which child was adopted?

The O child was adopted, even though the mother is type O, the father will contribute an A or a B allele to the offspring. These alleles are dominant.

7. A person with type A blood (unknown genotype) marries a person with type O blood. What blood types are possible among their children. (Show 2 crosses)

Child can be type A or type O blood.

8. Two people, both with AB blood have four children. What blood types should the children be?

Children will be 1/4 type A, 1/2 type AB, or 1/4 type B.

9. A person with type B blood (genotype BO) has children with a type AB person. What blood types are possible among their children?

punnettPossible Blood Types: A, AB, B


10. A person with type O blood is married to a person with type A blood (unknown genotype). They have 6 children, 3 of them have type A blood, three of them have type O blood. What is the genotype of the two parents?

The type A person myst be heteroyzous to have children who are both A and O. Parents are OO x AO

11. A person has type B blood. What are ALL the possible blood types of his parents. Show the crosses to prove your answer.

A x B ; A x AB;
B x AB; AB x AB,
B x O, B x B

12. A man of unknown genotype has type B blood, his wife has type A blood (also unknown genotype). List ALL the blood types possible for their children. (you may need to do multiple crosses to consider the different possible genotypes of the parents)

A, AB, B (everything but O is possible)

13. Two people with type O blood have three children. How many of those three children also have type O blood?

All will be O

14. Why is a person with type O blood called a "universal donor"? Type O blood can donate to any blood type

15. Why is a person with type AB blood called a "universal acceptor"? Type AB blood can receive transfusions from any blood type.