Enzymes are sensitive to

Options

A. Cold
B. Cell wall
C. Heat
D. Pressure.

Answer

**Step-by-Step Solution:**

1. **Understanding Enzymes**: Enzymes are biological catalysts that speed up chemical reactions in living organisms. They are proteins that have specific structures that allow them to function effectively.

2. **Factors Affecting Enzyme Activity**: Enzymes are sensitive to various environmental factors, including temperature, pH, and concentration of substrates. Among these, temperature is a critical factor.

3. **Optimum Temperature**: Each enzyme has an optimum temperature range where it functions best. For most human enzymes, this range is approximately between 35°C to 37°C.

4. **Effect of Low Temperature**: At temperatures below the optimum range (e.g., 0°C), enzyme activity decreases significantly, and they may become inactive. This is because the molecular motion slows down, leading to fewer collisions between enzymes and substrates.

5. **Effect of High Temperature**: As the temperature increases beyond the optimum range, the enzyme structure can start to denature. Denaturation means that the enzyme's active site changes shape, making it unable to bind to its substrate effectively. This process is irreversible at high temperatures.

6. **Conclusion**: Based on the understanding of how temperature affects enzyme activity, we can conclude that enzymes are sensitive to heat. Therefore, the correct answer to the question "Enzymes are sensitive to" is **heat**.

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