The structures that are formed by stacking of organized flattered membrances sacs in the chloroplasts are

Options

A. Stroma
B. Cristae
C. Grana
D. Stroma lamellae

Answer

To answer the question about the structures formed by stacking of organized flattened membrane sacs in the chloroplasts, we can break down the solution step by step:

### Step-by-Step Solution:

1. **Understanding Chloroplast Structure**:
- Chloroplasts are organelles found in plant cells that are essential for photosynthesis. They contain chlorophyll, the pigment that captures light energy.

2. **Identifying Key Components**:
- The chloroplast is surrounded by a double membrane. Inside, there are various structures, including thylakoids, stroma, and grana.

3. **Thylakoids**:
- Thylakoids are disc-shaped, flattened membrane sacs where the light-dependent reactions of photosynthesis occur.

4. **Stacking of Thylakoids**:
- When these thylakoids stack on top of each other, they form a structure known as a granum (plural: grana).

5. **Other Structures**:
- The stroma is the fluid-filled space surrounding the thylakoids, and stroma lamellae are the connections between different grana.

6. **Conclusion**:
- The question specifically asks for the structures formed by the stacking of organized flattened membrane sacs. Therefore, the correct answer is **grana**.

### Final Answer:
The structures that are formed by stacking of organized flattened membrane sacs in the chloroplasts are **grana**.

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