Question

Someone's fly from class escaped before analysis. You were able to catch it and noted the red eye color. Genotypically, is that one fly homozygous or heterozygous for red eyes? Describe how you could test your conclusion. (hint: punnett squares may help with your explanation.)

Answer 1

To detect the genotype of that fly ( either homozygous or heterozygous for red eye) test cross can be done. In test cross , the F1 progeny is crossed with homozygous recessive individual and results are analyzed. Here fly is red eye coloured is crossed with recessive characters white eye fly. Interpretation can be done as follows shown in attached image below.