Isolated chloroplasts release oxygen when illuminated. Supply of which of the following will increase the rate of oxygen production ?

Options

A. `NADP""^(+)`
B. `NAD""^(+)`
C. `FAD""^(+)`
D. ATP

Answer

To determine which supply will increase the rate of oxygen production in isolated chloroplasts when illuminated, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Process of Photosynthesis**:
- Photosynthesis occurs in chloroplasts, where light energy is converted into chemical energy. This process involves the absorption of light by chlorophyll and the fixation of carbon dioxide (CO2) to produce oxygen (O2).

2. **Identifying the Role of Chloroplasts**:
- Isolated chloroplasts can perform photosynthesis when illuminated. They utilize light energy to split water molecules, releasing oxygen as a byproduct.

3. **Considering the Factors Affecting Oxygen Production**:
- The question provides four options: NADPH, NAD+, ATP, and FAD. We need to determine which of these will enhance the rate of oxygen production.

4. **Analyzing Each Option**:
- **NADPH**: This is a reduced form of NADP+ and is crucial for the Calvin cycle, where it helps in the conversion of carbon dioxide into glucose. It also plays a role in the electron transport chain during photosynthesis.
- **NAD+**: This is the oxidized form of NADPH and is not directly involved in the process of oxygen production.
- **ATP**: While ATP is essential for energy transfer in the cell, it does not directly increase the rate of oxygen production in the context of isolated chloroplasts.
- **FAD**: This is another electron carrier but is not directly involved in the oxygen production during photosynthesis.

5. **Conclusion**:
- The supply of **NADP+** will increase the rate of oxygen production because it can be reduced to NADPH, which is essential for the photosynthetic process, particularly in the light-dependent reactions where oxygen is produced.

### Final Answer:
The supply of **NADP+** will increase the rate of oxygen production in isolated chloroplasts when illuminated.

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