Question

7. In mice the coat color called agouti results from a dominant allele A. Mice that are AA or Aa have agouti fur. Mice that are aa have black fur. However to get any coat color at all, at least one copy of a second dominant allele C of a different locus must be present. If a mouse has genotype cc, the mouse is albino regardless of what is happening at the other gene pair. Suppose two mice with genotypes AaCc are mated. What would be the expected phenotypes and their proportions? Hint: This is an epistasis problem. Assume independence. (4 points) 8. In a species of Bluebell, hairy leaf (S) is dominant to smooth leaf(s) and untoothed leaf (T) is dominant over toothed leaf (t). Open corolla (F) is dominant over fused corolla. A flower breeder is doing a monohybrid cross between a strain of bluebell known to be SSttFF and another strain known to be ssTTff. Assume independent assortment A. What is the genotype of F1 plants? (2 points) Suppose the breeder crosses an F1 with itself (or two F1's). are expected to be: B. What proportion of the F2's Hairy leaf, untoothed leaf, open corolla (2 points) Smooth leaf untoothed leaf fused corolla (2 points) C. Suppose 1 F2 survives and that plant has hairy leaves that are hairy leaf untoothed, fused corolla What is the likely-hood of that plant being SSTTff? (2 points)

Answer 1