In `C_(4)` plants, Calvin cycle operates in

Options

A. stroma of bundle sheath chloroplasts
B. grana of bundle sheath chloroplasts
C. grana of mesophyll chloroplsts
D. stroma of mesophyll chloroplasts

Answer

To determine where the Calvin cycle operates in C4 plants, we need to understand the structure and function of the chloroplasts in these plants.

### Step-by-Step Solution:

1. **Understanding C4 Plants**:
- C4 plants have a unique photosynthetic pathway that helps them efficiently fix carbon dioxide, especially in conditions where photorespiration is a concern.

2. **Identifying Key Structures**:
- In C4 plants, there are two types of cells involved in photosynthesis: mesophyll cells and bundle sheath cells.
- Mesophyll cells contain granulochloroplasts (which have thylakoids) and are primarily involved in the light reactions of photosynthesis.
- Bundle sheath cells contain agranulochloroplasts (which lack thylakoids) and are where the Calvin cycle occurs.

3. **Calvin Cycle Location**:
- The Calvin cycle, also known as the dark reaction, takes place in the stroma of chloroplasts.
- In C4 plants, the Calvin cycle specifically occurs in the stroma of the bundle sheath chloroplasts.

4. **Conclusion**:
- Therefore, the correct answer to the question is that in C4 plants, the Calvin cycle operates in the **stroma of bundle sheath chloroplasts**.

### Final Answer:
The Calvin cycle operates in the **stroma of bundle sheath chloroplasts** in C4 plants.

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