BIOI207 Introductory Genetics
Q1: A black mare crossed to a chestnut stallion produced a bay son and a bay daughter. The two offspring were mated to each other several times and they produced offspring of four different coat colours: black, bay, chestnut, and liver. Crossing a liver grandson back to the black mare gave a black foal, and crossing a liver granddaughter back to the chestnut stallion gave a chestnut foal. Explain how coat colour is being inherited in these horses (provide possible genotypes in your answer). (40 points)Q2: Two pure lines of plants are crossed, one with yellow petals and one with red. The F1 are all orange. When the F1 is selfed to give an F2, we find the following resultOrange: 182Yellow: 61Red: 77You consult an expert who says that these results could be explained by two competing hypotheses: incomplete dominance and recessive epistasis.a. Describe how incomplete dominance could explain these results. (15 points)b. Describe how recessive epistasis could explain these results. (15 points)c. Which of these hypotheses fit the data best? Answer using a fully articulated chi-squared test. (30 points)
