Cross a parent that is homozygous recessive for both traits (bbee) with a dihybrid (BbEe).

1. First, draw a Punnett square in your notes.
2. For each offspring in the Punnett square, determine the phenotype (fur color and eye color).
3. Finally, use that information to fill in the predicted fraction of each phenotype in the data table below.

\begin{tabular}{||c||c|c|c|c|}
\hline \hline & \begin{tabular}{c}
Black \\
Fur and \\
Black \\
Eyes
\end{tabular} & \begin{tabular}{c}
Black \\
Fur and \\
Red \\
Eyes
\end{tabular} & \begin{tabular}{c}
White \\
Fur and \\
Black \\
Eyes
\end{tabular} & \begin{tabular}{c}
White \\
Fur and \\
Red \\
Eyes
\end{tabular} \\
\hline \begin{tabular}{c}
Predicted \\
Fraction
\end{tabular} & [tex]$\square / 16$[/tex] & [tex]$\square / 16$[/tex] & [tex]$\square / 16$[/tex] & [tex]$\square / 16$[/tex] \\
\hline \hline
\end{tabular}



Answer :

Let's go through this step-by-step and determine the fractions for each phenotype.

### Step 1: Parent Genotypes
- Parent 1 genotypes: bbee (homozygous recessive for both traits)
- Parent 2 genotypes: BbEe (dihybrid)

### Step 2: Gametes
- Parent 1 can produce gametes: be
- Parent 2 can produce gametes: BE, Be, bE, be

### Step 3: Punnett Square
We create a Punnett square using the gametes from each parent. The gametes from Parent 1 will be along one axis (here, it produces only 'be'), and the gametes from Parent 2 will be along the other axis.

| | BE | Be | bE | be |
|-------|----|----|----|----|
| be| BbeE | Bbee | bbeE | bbee |

Let's list out each genotype and their corresponding phenotypes:

1. BbEe: Black Fur and Black Eyes
2. Bbee: Black Fur and Red Eyes
3. bbEe: White Fur and Black Eyes
4. bbee: White Fur and Red Eyes

### Step 4: Offspring Genotype and Phenotype
Considering that there are equal chances of forming each combination from the Punnett square, we can now determine the frequency of each phenotype:

1. BbEe: 4 out of 16 (Black Fur and Black Eyes)
2. Bbee: 4 out of 16 (Black Fur and Red Eyes)
3. bbEe: 4 out of 16 (White Fur and Black Eyes)
4. bbee: 4 out of 16 (White Fur and Red Eyes)

### Step 5: Predicted Fraction
We now summarize this information in a table:

[tex]\[ \begin{tabular}{||c||c|c|c|c|} \hline \hline & \begin{tabular}{c} Black \\ Fur and \\ Black \\ Eyes \end{tabular} & \begin{tabular}{c} Black \\ Fur and \\ Red \\ Eyes \end{tabular} & \begin{tabular}{c} White \\ Fur and \\ Black \\ Eyes \end{tabular} & \begin{tabular}{c} White \\ Fur and \\ Red \\ Eyes \end{tabular} \\ \hline \begin{tabular}{c} Predicted \\ Fraction \end{tabular} & \frac{4}{16} & \frac{4}{16} & \frac{4}{16} & \frac{4}{16} \\ \hline \hline \end{tabular} \][/tex]

Simplified, each fraction becomes:

[tex]\[ \begin{tabular}{||c||c|c|c|c|} \hline \hline & \begin{tabular}{c} Black \\ Fur and \\ Black \\ Eyes \end{tabular} & \begin{tabular}{c} Black \\ Fur and \\ Red \\ Eyes \end{tabular} & \begin{tabular}{c} White \\ Fur and \\ Black \\ Eyes \end{tabular} & \begin{tabular}{c} White \\ Fur and \\ Red \\ Eyes \end{tabular} \\ \hline \begin{tabular}{c} Predicted \\ Fraction \end{tabular} & \frac{1}{4} & \frac{1}{4} & \frac{1}{4} & \frac{1}{4} \\ \hline \hline \end{tabular} \][/tex]

Thus, the predicted fractions of each phenotype are:
- 1/4 for Black Fur and Black Eyes
- 1/4 for Black Fur and Red Eyes
- 1/4 for White Fur and Black Eyes
- 1/4 for White Fur and Red Eyes