The Punnett square below is for a test cross of two mice that were purebred for two different traits. Fill in the white boxes of the Punnett square with all possible offspring genotypes.

\begin{tabular}{|c|c|c|c|c|}
\hline
\begin{tabular}{l}
Punnett \\
Square
\end{tabular} & BE & BE & BE & BE \\
\hline be & [tex]$\square$[/tex] & [tex]$\square$[/tex] & [tex]$\square$[/tex] & [tex]$\square$[/tex] \\
\hline be & [tex]$\square$[/tex] & [tex]$\square$[/tex] & [tex]$\square$[/tex] & [tex]$\square$[/tex] \\
\hline be & [tex]$\square$[/tex] & [tex]$\square$[/tex] & [tex]$\square$[/tex] & [tex]$\square$[/tex] \\
\hline be & [tex]$\square$[/tex] & [tex]$\square$[/tex] & [tex]$\square$[/tex] & [tex]$\square$[/tex] \\
\hline
\end{tabular}



Answer :

To determine the offspring genotypes using a Punnett square, follow these steps carefully:

1. Identify the parental genotypes. As we are dealing with a dihybrid cross and assuming purebred organisms, we'll have one parent that is homozygous dominant for both traits (BE) and the other parent that is homozygous recessive for both traits (be).

2. List the possible gametes each parent can produce:
- The BE parent can only produce gametes containing BE.
- The be parent can only produce gametes containing be.

3. Set up the Punnett square:
- One side of the Punnett square will represent the gametes from the BE parent.
- The other side will represent the gametes from the be parent.

4. Fill in the Punnett square by combining the gametes from each parent:
- Since the BE parent can only produce BE gametes and the be parent can only produce be gametes, each cell in the Punnett square will be a combination of one BE gamete and one be gamete.

5. Combine the gametes in each cell:
- Each cell will show the combination BE + be, resulting in the genotype BbEe for all offspring.

Thus, the filled Punnett square will look like this:
[tex]\[ \begin{array}{|c|c|c|c|c|} \hline \text{Punnett Square} & BE & BE & BE & BE \\ \hline be & BbEe & BbEe & BbEe & BbEe \\ \hline be & BbEe & BbEe & BbEe & BbEe \\ \hline be & BbEe & BbEe & BbEe & BbEe \\ \hline be & BbEe & BbEe & BbEe & BbEe \\ \hline \end{array} \][/tex]

In conclusion, all the offspring in this cross will have the genotype BbEe, indicating they are heterozygous for both traits.