Respiration differs from combustion in which of the following ?

Options

A. Energy is released in respiration
B. Substance is oxidised
C. Enzymes are involved
D. All the above

Answer

To solve the question "Respiration differs from combustion in which of the following?", we can analyze the options provided:

1. **Energy is released in respiration**:
- In respiration, energy is indeed released in the form of ATP (adenosine triphosphate), which is utilized by living cells for various functions. In combustion, energy is released as heat. Therefore, while both processes release energy, this does not highlight a difference between them.

2. **Substance is oxidized**:
- Both respiration and combustion involve the oxidation of substances. In respiration, organic molecules (like glucose) are oxidized to produce energy, while in combustion, substances (like hydrocarbons) are also oxidized to release energy. Thus, this option does not indicate a difference.

3. **Enzymes are involved**:
- In cellular respiration, enzymes play a crucial role in facilitating the biochemical reactions that convert substrates into energy. On the other hand, combustion is a chemical reaction that occurs without the involvement of enzymes. This is a significant difference between the two processes.

4. **All of the above**:
- Since options 1 and 2 do not represent differences between respiration and combustion, this option cannot be correct.

Based on the analysis, the correct answer is that respiration differs from combustion in that **enzymes are involved** in respiration, while they are not involved in combustion.

### Final Answer:
Respiration differs from combustion in that **enzymes are involved** in respiration.