Answer to Question #317837 in Genetics for Nhlonipho Manganyi

Question

A researcher has two pure breeding strains of fruit flies: strain A and strain B.

Strain A produces only enzyme A and strain B only enzyme B. The alleles coding for enzyme A and enzyme B are the only alleles involved here and occur at the same locus.

The researcher crossed a fly from strain A with one from strain B and found that all the offspring (F1 generation) could produce both enzyme A and enzyme B. When he crossed two of the F1 generation flies, he found the following in the offspring:

658 produced enzyme A, 1364 produced enzyme A and B, 581 produced enzyme B

1. Show the researcher’s cross up to the F2 generation using appropriate symbols for strain A (symbol: A) and strain B (symbol: B) by completing the missing values in the following table. For ratios write down the lowest possible rounded whole numbers, and write 0 if no value is required; write all values according to expected Mendelian Genetics principles, not the actual numbers obtained by the researcher.