Question

(6 pts) In a unique species of bird, feathers may be white, blue, red, or pink. All colors may be true breeding. Color is determined by two unlinked autosomal genes. If true-breeding birds with blue feathers are crossed to true-breeding red-feathered birds, all F1 birds have white feathers. F1 birds were allowed to intercross to generate the F2 generation. Amongst the F2, the following ratio was observed: 9/16 white: 3/16 blue: 3/16 red: 1/16 pink In still another cross, using true-breeding parents, white-feathered birds are crossed with pink-feathered birds. Again, all F1 birds had white feathers and the F2 showed a 9:3:3:1 ratio, as just shown.

A) Describe the inheritance of feather color by defining gene symbols and designating which genotypes give rise to the four phenotypes. (Use dashes where appropriate.)

B) Determine the F1 and F2 results of a cross between true-breeding red and true-breeding pink feathered birds. Show genotypes and phenotypes.

Answer 1