Both respiration and photosynthesis require the following

Options

A. Sunlight
B. Chlorophyll
C. Glucose
D. Cytochromes

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for a compound that is required in both respiration and photosynthesis.

2. **Identifying the Processes**:
- **Photosynthesis**: This process occurs in plants where light energy is converted into chemical energy. It primarily takes place in the chloroplasts.
- **Respiration**: This is the process by which cells convert glucose and oxygen into energy, carbon dioxide, and water. It occurs in the mitochondria.

3. **Key Components in Photosynthesis**:
- Photosynthesis involves chlorophyll, sunlight, water, and carbon dioxide.
- The light energy is captured by chlorophyll and used to convert carbon dioxide and water into glucose and oxygen.

4. **Key Components in Respiration**:
- Respiration involves glucose and oxygen as reactants to produce energy (ATP), carbon dioxide, and water.
- The process includes an electron transport chain where electron carriers play a crucial role.

5. **Identifying Common Components**:
- The question specifically seeks a compound that is common to both processes.
- Cytochromes are essential in both respiration and photosynthesis.

6. **Role of Cytochromes**:
- In **Respiration**: Cytochromes act as electron carriers in the electron transport chain, facilitating the transfer of electrons and helping in ATP production.
- In **Photosynthesis**: Cytochromes are part of the photosystems in the thylakoid membranes, where they help in trapping light energy.

7. **Conclusion**: The compound required in both respiration and photosynthesis is **cytochromes**.

### Final Answer:
Both respiration and photosynthesis require **cytochromes**.

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