Question

In a fruit fly experiment, grey body, normal winged (homozygous dominant) fruit flies were mated with black body, short winged (homozygous recessive) fruit flies. The F1 dihybrid females were then used in a test cross. If the genes are always linked and no crossing over occurs, what would be the predicted ratio in the F2 generation?
A. 9:3:3:3
B. 1:1:1:1
C. 3:1
D. 1:1

Answer 1

Answer:

In a fruit fly experiment, grey body, normal winged (homozygous dominant) fruit flies were mated with black body, short winged (homozygous recessive) fruit flies. The F1 dihybrid females were then used in a test cross. If the genes are always linked and no crossing over occurs, what would be the predicted ratio in the F2 generation?

GG x bb = Gb, Gb, Gb and Gb  F1 generation

grey body heterozygous offspring 4:0

Gb x Gb= GG, Gb, Gb, and bb F2 generation

3:1 three grey body fly and one black body fly

Explanation: