Which cell structure is present in plant cells but not in animal cells ?

Options

A. Cell membrane
B. Cell wall
C. Cytoplasm
D. Mitochondria

Answer

**Step-by-Step Solution:**

1. **Understanding Cell Structures**: First, we need to identify the various structures present in both plant and animal cells. Common structures include the cell membrane, cytoplasm, and mitochondria.

2. **Identifying Unique Structures**: Next, we focus on the structures that are unique to either plant or animal cells. We look at the options provided:
- Cell membrane
- Cell wall
- Cytoplasm
- Mitochondria

3. **Analyzing Each Option**:
- **Cell Membrane**: This is present in both plant and animal cells, so it cannot be the answer.
- **Cytoplasm**: This is also found in both types of cells, eliminating it as a unique structure.
- **Mitochondria**: These organelles are present in both plant and animal cells, so this option is also not unique to plant cells.
- **Cell Wall**: This structure is specifically found in plant cells and is not present in animal cells.

4. **Conclusion**: Since the cell wall is the only structure listed that is present in plant cells but not in animal cells, we conclude that the correct answer is **B, cell wall**.

5. **Definition of Cell Wall**: The cell wall is a structural layer that surrounds the cell membrane in plant cells. It provides support and rigidity to the plant cell, helping it maintain its shape.

**Final Answer**: The cell structure that is present in plant cells but not in animal cells is the **cell wall**.

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