A flattened disc-like sturcture present in chloroplast

Options

A. Stroma
B. Thylakoids
C. Loculus
D. Margin

Answer

To answer the question "A flattened disc-like structure present in chloroplast," we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Structure in Chloroplasts**:
- Chloroplasts are the organelles responsible for photosynthesis in plant cells. They contain various structures that play specific roles in this process.

2. **Examine the Options**:
- The options provided are stroma, thylakoids, loculus, and margin. We need to determine which of these is a flattened disc-like structure.

3. **Understand the Components of Chloroplasts**:
- **Stroma**: This is the fluid-filled space inside the chloroplast where the Calvin cycle takes place. It is not a disc-like structure.
- **Thylakoids**: These are indeed flattened disc-like structures that are stacked to form granum. They contain chlorophyll, which is essential for photosynthesis.
- **Loculus**: This term generally refers to a small cavity or chamber and is not specific to chloroplast structures.
- **Margin**: This term does not refer to a specific structure within chloroplasts.

4. **Conclude with the Correct Answer**:
- Based on the definitions and descriptions of the components of chloroplasts, the correct answer is **thylakoids**. They are the flattened disc-like structures present in chloroplasts.

### Final Answer:
The flattened disc-like structure present in chloroplast is **thylakoids**.

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