Question

1. Draw a single Punnett square to represent the results of a cross between a male fruit fly with genotype BbEe and a female fruit fly with genotype bbEe. a) In your Punnett square, draw the chromosomes carried by the gametes produced by the two parents in the top row and left column. Label all alleles on all chromosomes. b) In your Punnett square, record the genotypes of the offspring that result from this cross. (You do not need to draw the chromosomes found in the offspring.)

What fraction of the offspring of the cross in the previous question are expected to have a) Brown eyes? ______ b) Ebony bodies? _______ c) Brown eyes and ebony bodies?

Answer 1

Assuming that B allele is Brown and E allele is ebony.

Fraction of offsprings with brown eyes - 1/2

Fraction of offsprings with ebony bodies - 3/4

Fraction of offsprings having brown eyes and ebony bodies - 3/8