Question

Students in a class are studying patterns of inheritance using genes involved in determining the body color and wing shape of Drosophila flies. Each of the genes has only two alleles, one of which is completely dominant to the other. Each student in the class performed a parental cross between a fly that is true-breeding for ebony body and vestigial wings and a fly that is true-breeding for gray body and long wings. Each student then crossed several pairs of the F1 flies and determined the phenotypes of 500 of the resulting F2 flies with respect to body color and wing shape. The students in the class averaged their data for the frequencies of the four possible phenotypes (Table 1). Fly Phenotype Number of Flies (22 SEmean) 98 10 28 7 Ebony body and long wings Ebony body and vestigial wings Gray body and long wings Gray body and vestigial wings 293 25 81 10 The students performed a second cross. The parental cross was between flies that are true-breeding for gray bodies and long wings and flies that are true-breeding for ebony bodies and curly wings. They crossed pairs of F, flies and determined the phenotypes of the resulting F2 flies. The students found an approximate 3:1 ratio of flies with the dominant phenotype (gray bodies and long wings) to flies with the recessive phenotype (ebony bodies and curly wings). Only a few of the flies expressed the dominant phenotype of one trait and the recessive phenotype of the other trait Period d) Predict the most likely cause of the F2 ratio obtained by the students in the second analysis between parental flies that are true-breeding for gray bodies and long wings and flies that are true-breeding for ebony bodies and curly wings. Provide reasoning to justify your prediction

Answer 1

I think that the ration of gray to long will be hurastically different unfortunately I’m not sure but I think very different