Question

4. Show a dihybrid cross for fruit flies. GgEe x GgEe. Be careful when counting the

number for each phenotype, it is easy to make a mistake.

Answer 1

ABSWER:

The cross between two heterozygotes (Normal wings and Red eyes) will produce 16 offspring. The number of offspring with different phenotypes are given below:

The number of flies with normal wings, red eyes is 9.

The number of flies with normal wings, sepia eyes is 3.

The number of flies with vestigial wings, red eyes is 3.

The number of flies with vestigial wings, sepia eyes is 1.

The ration of the offspring with the phenotype normal wings, red eyes : normal wings, sepia eyes : vestigial wings, red eyes: vestigial wings, sepia eyes is 9:3:3:1.