A granum is made up of:

Options

A. Stacks of membrane-bounded, flattened discoid sacs called thylakoids containing the molecules of chlorophyll.
B. A coin-shaped stack of thylakoids, membrane-like structures in the chloroplasts of plant cells. Grana are separately present to form stromal thylakoids.
C. Many thylakoids arranged one beside the other
D. None of the above

Answer

To answer the question "A granum is made up of:", we can break down the information step by step.

### Step-by-Step Solution:

1. **Understanding Granum**:
- A granum is a structure found in chloroplasts, which are the organelles responsible for photosynthesis in plant cells.
- The term "granum" is singular, while its plural form is "grana."

2. **Structure of Chloroplast**:
- Chloroplasts are double membrane-bound organelles. They consist of an outer and an inner membrane.
- Inside the chloroplast, there is a fluid-filled space called the stroma.

3. **Thylakoids**:
- Within the stroma, there are individual structures that resemble coins, known as thylakoids.
- Thylakoids are membrane-bound and are the sites where chlorophyll, the green pigment essential for photosynthesis, is located.

4. **Formation of Granum**:
- A granum is formed by a stack of these thylakoids.
- The stacks of thylakoids are interconnected by structures called stromal lamellae.

5. **Conclusion**:
- Therefore, a granum is made up of stacks of membrane-bounded flattened discoidal sacs called thylakoids, which contain the molecules of chlorophyll.

### Final Answer:
A granum is made up of stacks of thylakoids containing chlorophyll.

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