Assignment #4:  This assignment is due at the beginning of the final exam.  Print off this page, plus turn in a page of HANDWRITTEN answers with your name and lecture section time (i.e. 8am MWF or 1pm MWF).  Make sure to include Punnett squares for each answer.

1.  Pure breeding yellow guinea pigs crossed with pure breeding white ones produce only cream-colored offspring.  This pattern indicates incomplete dominance for the coat color trait.  Rough hair is dominant to smooth hair.  Give the genotypes, phenotypes, genotype ratios, and phenotype ratios of the parents and offspring of a cross between a smooth white guinea pig with a heterozygous rough cream-colored guinea pig.

2.  In cats an X-linked pair of alleles, B and b, control color of fur.  The alleles are incompletely dominant:  B produces black, b produces yellow, and Bb produces tortoise-shell (a mix of black and yellow hairs).
a.  A yellow cat had a litter of two tortoise-shell kittens and one yellow kitten.  What is the sex of the yellow kitten?  What are the sexes of the tortoise-shell kittens?
b.  A tortoise-shell cat brings home a litter of black, yellow, and tortoise-shell kittens.  The color of which sex of kittens would tell you the color of the tomcat that produced them?
c.   A yellow male is crossed with a tortoise-shell female.  If the female has all male kittens in her litter of four, what color(s) would they be?
d.  A tortoise-shell cat brings home her litter of black, yellow, and tortoise-shell kittens.  You suspect that the black tomcat next door is the father.  How would you determine whether he was the father (i.e. can you tell from the sex/color combinations in the kittens)?