Question

Cross a brown homozygous recessive mouse with a black heterozygous mouse and determine the

percentages of the possible phenotypes and genotypes. (________/10)
Gametes
b.
Cross
P2:
Phenotype and Genotype percentages
Black
hetero
mouse
Brown Mouse > homoz2||
enter

Answer 1

The brown homozygous recessive mouse has a genotype of bb, while the black heterozygous mouse has a genotype of Bb.

When these two mice are crossed, the possible genotypes for their offspring are Bb and bb, while the possible phenotypes are black and brown fur.

Using a Punnett square, we can determine the possible genotypes and phenotypes of the offspring:

| | B | b |
| - | - | - |
| b | Bb| bb|
| b | Bb| bb|

As we can see, the possible genotypes of the offspring are Bb and bb, with a 50% chance of each. The possible phenotypes are black and brown fur, with a 50% chance of each.

Therefore, the percentages of the possible phenotypes and genotypes are:
- 50% chance of having black fur (Bb)
- 50% chance of having brown fur (bb)
- 50% chance of being heterozygous black (Bb)
- 50% chance of being homozygous brown (bb)