Which is not a characteristic of chloroplasts?

Options

A. A chloroplast is surrounded by a double membrane
B. Chlorophyll absorbs solar energy that is used to form chemical bonds
C. Stacks called grana are linked by membranous connections
D. Chlorophylls are found in the fluid stroma of the chloroplast

Explanation

To determine which option is not a characteristic of chloroplasts, we will analyze each of the provided statements about chloroplasts one by one.

### Step-by-Step Solution:

1. **Chloroplasts are surrounded by a double membrane.**
- Chloroplasts indeed have an outer and an inner membrane, making this statement true.

2. **Chlorophyll absorbs solar energy that is used to form chemical bonds.**
- Chlorophyll, the green pigment found in chloroplasts, absorbs sunlight and plays a crucial role in photosynthesis by converting solar energy into chemical energy. This statement is also true.

3. **Stacks called grana are linked by membranous connections.**
- Chloroplasts contain structures called thylakoids, which are organized into stacks known as grana. These grana are interconnected by membranous structures, confirming that this statement is correct.

4. **Chlorophylls are found in the fluid stroma of the chloroplasts.**
- This statement is incorrect. Chlorophyll is located in the thylakoid membranes, not in the stroma. The stroma is the fluid-filled space surrounding the thylakoids, but it does not contain chlorophyll.

### Conclusion:
The statement that is not a characteristic of chloroplasts is: **"Chlorophylls are found in the fluid stroma of the chloroplasts."**

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