During respiration, breakdown of respiratory substrate takes place in small steps or stages. This ensures :-

Options

A. Trapping of released energy into ATP
B. Constant temperature throghout the process of respiration
C. Production of number of useful intermediates
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding Respiration:**
- Respiration is a biochemical process where organic substrates (like glucose) are broken down to release energy. This process occurs in multiple stages rather than a single step.

2. **Example of Glycolysis:**
- In glycolysis, glucose is broken down into pyruvate through a series of 10 enzymatic reactions. Each step involves different intermediates and enzymes.

3. **Formation of Intermediates:**
- The breakdown in small steps allows for the formation of various intermediates. These intermediates can serve as substrates for other metabolic pathways, making the process more versatile.

4. **Energy Release in Small Amounts:**
- Each step of respiration releases a small amount of energy. This is crucial because it allows the cell to capture this energy efficiently in the form of ATP (adenosine triphosphate).

5. **Temperature Regulation:**
- If respiration occurred in a single large step, the energy released would be substantial, leading to a rapid increase in cellular temperature. This could denature enzymes and disrupt cellular functions.

6. **Enzyme Activity:**
- By releasing energy gradually, the temperature remains stable, ensuring that enzymes remain active and functional throughout the process.

7. **Conclusion:**
- Therefore, the breakdown of respiratory substrates in small steps ensures efficient energy capture, temperature regulation, and the production of useful intermediates, which are essential for cellular metabolism.

**Final Answer:**
The breakdown of respiratory substrates in small steps ensures efficient energy capture, temperature regulation, and the production of useful intermediates.

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