Which of the following is the common purpose for the mesosomes in a bacterial cell, cristae in a mitochondrion and grana in a chloroplast ?

Options

A. Oxidation of food
B. ATP synthesis by photophosphorylation
C. Increase the surface area
D. Utilization of `O_(2)` for ATP syntheis.

Answer

To solve the question regarding the common purpose of mesosomes in bacterial cells, cristae in mitochondria, and grana in chloroplasts, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structures**:
- **Mesosomes**: These are invaginations of the plasma membrane in bacterial cells. They are involved in various functions, including cell division and respiration.
- **Cristae**: These are the folds of the inner membrane in mitochondria. They increase the surface area for the electron transport chain, which is crucial for ATP production.
- **Grana**: These are stacks of thylakoids in chloroplasts where the light-dependent reactions of photosynthesis occur. They also increase the surface area for capturing light energy.

2. **Identify the Functions**:
- The primary function of mesosomes is to increase the surface area for metabolic processes in bacteria.
- Cristae serve to increase the surface area for ATP synthesis in mitochondria.
- Grana increase the surface area for light absorption and photosynthesis in chloroplasts.

3. **Common Purpose**:
- The common purpose among mesosomes, cristae, and grana is to **increase surface area**. This increase in surface area allows for more efficient metabolic processes, whether it be respiration in bacteria, ATP production in mitochondria, or photosynthesis in chloroplasts.

4. **Evaluate the Options**:
- **Option 1: Oxidation of food** - Incorrect, as oxidation occurs in mitochondria specifically.
- **Option 2: ATP synthesis by Photophosphorylation** - Incorrect, as photophosphorylation is specific to chloroplasts and not a common function.
- **Option 3: Increase the surface area** - Correct, as all three structures serve to increase surface area for their respective functions.
- **Option 4: Utilization of oxygen for ATP synthesis** - Incorrect, as this is specific to mitochondria during aerobic respiration.

5. **Conclusion**:
- The correct answer is **Option 3: Increase the surface area**.