Select the correct location.

In pea plants, the allele for inflated pod seed (I) is dominant over the allele for constricted pod seed (i). The Punnett square shows a cross for this trait. Which offspring will be homozygous dominant?

[tex]\[
\begin{tabular}{|c|c|c|}
\hline
& I & I \\
\hline
i & Ii & Ii \\
\hline
i & Ii & Ii \\
\hline
\end{tabular}
\][/tex]

A. Top-left cell (Ii)
B. Top-right cell (Ii)
C. Bottom-left cell (Ii)
D. Bottom-right cell (Ii)



Answer :

Let's solve this step-by-step to determine which offspring will be homozygous dominant (II) in the given Punnett square.

1. Set up the Punnett square:

We'll first create the structure of the Punnett square for the cross between two pea plants.

| | I | I |
|---------|---------|---------|
| I | II | II |
| i | Ii | Ii |

The columns represent the alleles contributed by one parent, and the rows represent the alleles contributed by the other parent.

2. Complete the entries in each cell:

- The cell (1,1) represents the combination of one I from the top row and one I from the side column, resulting in "II".
- The cell (1,2) represents the combination of one I from the top row and one i from the side column, resulting in "Ii".
- The cell (2,1) represents the combination of one I from the top row and one I from the side column, resulting in "II".
- The cell (2,2) represents the combination of one I from the top row and one i from the side column, resulting in "Ii".

Therefore, the filled Punnett square looks like this:

| | I | I |
|---------|---------|---------|
| I | II | II |
| i | Ii | Ii |

3. Identify the homozygous dominant offspring:

Homozygous dominant offspring have both alleles as the dominant allele (I), so they will be represented as "II".

From the Punnett square, we can see that the cell in row 1, column 1 is "II", and the cell in row 1, column 2 is also "II". Specifically:

- The cell at position (0, 0) (row 1, column 1) contains "II".

4. Summarize the findings:

The homozygous dominant offspring (with genotype II) are found in the cell at position (0, 0) in the Punnett square. There is only one homozygous dominant offspring in this cross.

Thus, the correct answer is that there is 1 homozygous dominant offspring, located at position (0, 0) in the Punnett square.