What are quantasomes? Why are these called photosynthetic units?

Explanation

### Step-by-Step Solution:

1. **Definition of Quantasomes**:
- Quantasomes are rounded structures found on the inner surface of thylakoids, which are membranous sacs located within chloroplasts.

2. **Structure of Chloroplast**:
- Chloroplasts are double-membrane organelles consisting of an outer membrane and an inner membrane. The space enclosed by the inner membrane is called the stroma.

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