NAME: _________________________
Blood Genetics Group Practice
1. What is on the surface of the red blood cells of people with blood types: A, B, and AB, but not O?
2. What are the genes or alleles for blood type?
3. Which is the recessive allele or gene for blood type?
4. Which blood type is called the “Universal Donor?” Why?
5. Which blood type is called the “Universal Receiver?” Why?
6. Assume heterozygosity (“Aa”) for the following: Aaron and Gwen met and married. Gwen has
type AB blood, Aaron has type B blood. Four years later they had 3 children with the following
blood types: 1 with blood type AB, 1 with blood type B, and the youngest has blood type A. Aaron
has suspicions that the youngest child could belong to the Pepsi Delivery Guy who has been found
to have blood type O (he cut his hand on a delivery and Aaron had it checked). Is Aaron correct?
Is it the Pepsi Guy? Whose kid is this one most likely?
7. Assume Heterozygosity for the following: David is not sure that he’s from the same family as his sister,
Rachel, and mother, Helena Sterling, and father, David Sterling Sr. David Sr.’s blood type is AB, while
Helena’s blood type is B. David’s sister Rachel is blood type AB and David’s is blood type A. Is David
correct in thinking he was adopted or could he be a member of the family?
8. True story: movie superstar Charlie Chapman from the black and white era was accused by Miss Berry
of being the father of her child. This became a huge scandal as Ms. Joan Berry was an actress working
for Charlie Chaplin studios. The court case became suspended until learning the blood type of the child
to determine if it belonged to Charlie. The baby’s blood type was B, Ms. Berry was type A, and Charlie
was type O. The court found in favor of Ms. Berry and ordered Mr. Chaplin to pay child support. Was
this correct?
9. What are the percent probabilities of the offspring's genotype (or genes) produced by the
following crosses? ** Use 100%, 75%, 50%, or 25% for each. **
a. A x A – Please do AA X AA + AO X AA + AO X AO
b. B x B – See above
c. O x O
d. A x B Please do: AA X BB; AO X BB; AO X BO; AA X BO
e. AB x AB
f. A x AB; Please do AA X AB + AO X AB
g. B X AB – See Above