Blood type is controlled by 3 alleles: A, B, O. A & B are codominant, O is recessive.
1. a) What are the two genotypes possible for a person who as A blood? ____ AA, AO ___
b) What genotype does a person with AB blood have? ____ AB _______
c ) What genotype does a person with O blood have? ____ OO ______
d) What are the two genotypes possible for a person who as B blood? ______ BB, BO _____
2. A man with type AB blood is married to a woman also with type AB blood. What percentage of their children will have:
A blood? ___ 25% ___ B blood? _ 25% ___ O blood _ 0% ____ AB blood _ 50% ______
3. A man has type B blood (genotype BB) is married to a woman with type O blood. What blood type will all their children have? ___ _B_ __ What is the genotype of the children? __ BO ____
4. A woman with type A blood (genotype AO) is married to a type B person (genotype BO). What proportion of their children will have:
A blood? __ 25% ____ B blood? __ 25% ___ O blood __ 25% __ AB blood __ 25% _____
5. A woman with type A blood is claiming that a man with type AB blood is the father of her child who is type B.
Could this man be the father of the child? ___ yes _________ Show the possible crosses; remember that the woman can have AA or AO genotypes.
Assuming that he is the father, what must the mother's genotype be? _ AO _
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. Jane has type A blood, Bobby has type B blood, and Grace has type O blood. Which child was adopted? _____ Grace _______
Teacher's note- students may have less trouble with these if you tell them to assign them letters like blood type letter, A, B, and O
7. Show Genotypes
8. If a star-eyed smiley (homozygous) is crossed with a dot-eyed smiley (also homozygous) what will all of their offspring look like?
SS x DD , all offspring SD
9. If the pair in the cross above were both heterozygous, what percentage of the offspring will be: SD x SD
Starry __ 25% __ Star-dot _ 50% ____ Dot __ 25% _ Square __ 0% __
10. If a starry-dot eyed smiley is crossed with a square eyed smiley what percentage of the offspring will be:
Starry _ 50% ___ Star-dot ______ Dot __ 50% __ Square ____
11. If two starry-dot eyes smileys are crossed, what percentage of the offspring will be:
Starry _ 25% ___ Star-dot __ 50% __ Dot _ 25% ___ Square _ 0% __
Determine the genotypes of the following Sunnys. It is a multiple allele trait, spiked and circles are codominant and the bare trait is recessive.
12. Show genotypes: SS, SC, CC, OO
13. If a spiked sunny (heterozygous) is crossed with a bare sunny, what percentage of the offspring will be bare? ___ 50% ______
What percentage will be spiked? ___ 50% ______
14. If a spike-circle sunny is crossed with a heterozygous spike sunny, how many of the offspring will be spiked? ___ 50% __
How many will be circles? ___ 25% _______
How many will be spike-circles? _______ 25% ______
15. A female sunny who is spiked is married to a male sunny who is circle. They have a child who is bare. What must be the genotypes of the two parents? ___ SO x CO _____________
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