A male mouse with brown fur color is mated to two different female mice with black fur. Black female 1 produces a litter of 9 black and 7 brown pups. Black female 2 produces 14 black pups.
Choose symbols for each allele, and identify the genotypes of the brown male and the two black females.

Verified step by step guidance

1. Step 1: Define the symbols for the alleles. Let 'B' represent the dominant allele for black fur and 'b' represent the recessive allele for brown fur. Black fur is dominant over brown fur.
2. Step 2: Analyze the offspring from Black Female 1. The litter consists of 9 black and 7 brown pups. This indicates that Black Female 1 must be heterozygous (Bb), as she produces both black and brown offspring when mated with the brown male.
3. Step 3: Determine the genotype of the brown male. Since the male mouse has brown fur, he must be homozygous recessive (bb), as brown fur is recessive and requires two copies of the 'b' allele.
4. Step 4: Analyze the offspring from Black Female 2. The litter consists of 14 black pups and no brown pups. This suggests that Black Female 2 is homozygous dominant (BB), as she only produces black offspring regardless of the male's genotype.
5. Step 5: Summarize the genotypes: The brown male is bb, Black Female 1 is Bb, and Black Female 2 is BB. These genotypes explain the observed offspring ratios in the litters.

Key Concepts

Mendelian Genetics

Mendelian genetics is the study of how traits are inherited through generations based on the principles established by Gregor Mendel. It involves understanding dominant and recessive alleles, where dominant alleles mask the expression of recessive ones. This framework helps predict offspring traits based on parental genotypes.

Alleles and Genotypes

Alleles are different forms of a gene that determine specific traits, such as fur color in mice. Each individual has two alleles for each gene, one inherited from each parent, which together form the genotype. The genotype influences the phenotype, or observable traits, of the organism.

Punnett Squares

Punnett squares are a tool used in genetics to predict the probability of offspring genotypes from parental genotypes. By organizing the possible allele combinations from each parent, Punnett squares help visualize the inheritance patterns and determine the expected ratios of different phenotypes in the offspring.