1.. Refer to the pedigree chart above for a family, some of whose members exhibit the dominant trait, wooly hair (W). Affected individuals are indicated by a filled in square or circle.

a.   What is the genotype for individual II – 4?  II – 5?  III – 1?  IV 3?  b.   What is the likelihood that the progeny of IV 3 and 4 will have wooly hair?    c.  If individual II – 3 married someone with wooly hair, could you determine the        expected likelihood a child would have wooly hair?  Why or why not?

1. Brown eyes are dominant over blue eyes. A brown-eyed man whose father had brown
   eyes and whose mother had blue eyes married a blue-eyed woman whose father and mother both had brown eyes. The couple has a blue-eyed son. Construct a pedigree for this family, showing all the genotypes for which you can be certain, and indicate the possible genotypes of individuals whose genotypes cannot be determined from the information given. What further information could you use to determine the genotypes of those individuals?
2. A and B blood types are codominant, and each is dominant to type O. Irene knows her blood type is A, but William does not know his blood type. However, William knows that his mother and father were type B. Irene’s and William’s first child is a boy named Gregory. Gregory has type O blood. Their 2nd child, a daughter names Lisa, has type AB blood. Construct a Punnett square for Irene and William. List all the possible phenotypes and genotypes (with expected frequencies) for their (future) children.
3. On Planet Q, two genes (on separate chromosomes) are involved in hair color and curliness. Assume both of the following conditions apply: a. Hair color involves 2 alleles which show incomplete dominance:
   Homozygotes for 1 allele have blue hair (BB).
   Homozygotes for the 2nd allele have yellow hair (YY)
   Heterozygotes have green hair (BY)

. b. Curly hair is completely dominant to straight hair. (You must define your alleles).

 Using a Punnett square, show the expected offspring if a man with straight green hair   man marries a woman with heterozygous curly green hair.   What would be the     expected phenotypes (and percents) of the offspring?  Be sure to label the symbols you  use.

1. Imagine a family with the following traits

A man, Paul has free earlobes. His wife Jane has attached earlobes, and they have a daughter with free earlobes, and a son with attached earlobes.

Paul has a sister, Mary with free earlobes. Mary’s husband George also has free earlobes, but their daughter has attached earlobes.

Paul has a brother, Peter, with attached earlobes. His wife Sally has attached earlobes. They have 2 children, a boy and girl, both with attached earlobes.

Paul’s father, Fred, has free earlobes, and his mother, Tina has attached earlobes.

Using correct symbols, and indicating which trait you are showing as colored boxes, draw a pedigree for this family. Fill in as many genotypes on the pedigree as possible. Are free earlobes dominant or recessive? How can you tell?

Sample Solution