A geneticist from an alien planet that prohibits genetic research escaped to Earth and brought with him two true-breeding lines of frogs. One frog line croaks by uttering “rib-it, rib-it” and has purple eyes. The other frog line croaks by muttering “knee-deep, knee-deep” and has green eyes. He mated the two frog lines, producing F1 frogs that were all utterers with blue eyes. A large F2 generation was produced by these hybrids in the following proportions.
27/64 blue-eyed, utterer
12/64 green-eyed, utterer
9/64 blue-eyed, mutterer
9/64 purple-eyed, utterer
4/64 green-eyed, mutterer
3/64 purple-eyed, mutterer
a. How many total gene pairs are involved in the inheritance of both eye color and croaking?
b. Of these genes, how many alleles control eye color and how many control croaking?
c. Assign gene symbols for all phenotypes, and indicate the genotypes of the P, F1, and F2 frogs.
d. After many years, the frog geneticist isolated true breeding lines of all six F2 phenotypes. Indicate the F1, and F2 phenotypic ratios of a cross between a blue-eyed, mutterer and a purple-eyed, utterer.
