11/11/13

Genetic Crosses that Involve 2 Traits 

In rabbits, grey hair is dominant to white hair.
Also in rabbits, black eyes are dominant to red eyes.

GG = gray hair
Gg = gray hair
gg = white hair
BB = black eyes
Bb = black eyes
bb = red eyes

1. What are the phenotypes (descriptions) of rabbits that have the following genotypes:

Ggbb ____________________ ggBB ________________________
ggbb ____________________ GgBb _________________________

2. A male rabbit with the genotype GGbb is crossed with a female rabbit with the genotype ggBb The square is set up below. Fill it out and determine the phenotypes and proportions in the offspring.

How many out of 16 have grey fur and black eyes? ______ How many out of 16 have grey  fur and red eyes? ________ How many out of 16 have white fur and black eyes? ______ How many out of 16 have white fur and red eyes? _______