Answer to Question #146547 in Genetics for Oliver Atkinson

Question

Carry out a genetic cross of your choice and work out the ratio of F1 and F2 offspring

Answer 1

A cross of two between an individual homozygous dormant for a trait (AA) with an individual homozygous recessive for a trait (aa) will produce offpsings all heterozygous dominant for the trait (Aa) in the F1 generation with a ratio of 1:1 or simply 1, as shown below.

When the offsprings from the F1 generation are selfed, the F2 generation will b composed of 3 heterozygous offspring for the trait (Aa) and a single homozygous individual for the trait (aa) hence producing a ratio to a 3:1 in the F2 generation, as shown in the diagram below.