Answer :
To solve the monohybrid cross using a Punnett Square for the given scenario:
1. Determine the genotypes of the parent mice:
- Male: Heterozygous dark coat genotype - Dd
- Female: Heterozygous dark coat genotype - Dd
2. Create a Punnett Square to show the possible combinations of alleles in the offspring:
| D | d |
------------------------
D | DD | Dd |
------------------------
d | Dd | dd |
3. Identify the possible genotypes and phenotypes of the offspring:
- Genotypes: DD, Dd, Dd, dd
- Phenotypes: Dark coat, Dark coat, Dark coat, Cream coat
4. Determine the genotypic and phenotypic ratios of the offspring:
- Genotypic ratio: 1 DD : 2 Dd : 1 dd
- Phenotypic ratio: 3 Dark coat : 1 Cream coat
In conclusion, the offspring resulting from crossing the heterozygous dark-coated male and female will have a genotypic ratio of 1 DD : 2 Dd : 1 dd and a phenotypic ratio of 3 Dark coat : 1 Cream coat. This Punnett Square analysis helps predict the possible outcomes of the genetic combination.