An enzyme shows maximum catalytic activity

Options

A. Above optimum temperature
B. Below optimum temperature
C. At optimum temperature
D. None of the above

Answer

To answer the question "An enzyme shows maximum catalytic activity when," we need to understand the concept of enzyme activity and the factors that influence it. Here’s a step-by-step breakdown of the solution:

### Step-by-Step Solution:

1. **Understanding Enzymes**: Enzymes are biological catalysts that speed up chemical reactions in the body. Each enzyme has a specific structure that allows it to bind to its substrate and facilitate a reaction.

2. **Catalytic Activity**: The catalytic activity of an enzyme refers to its ability to increase the rate of a reaction. This activity is influenced by various factors, including temperature, pH, and substrate concentration.

3. **Optimum Temperature**: Each enzyme has an optimum temperature at which it exhibits maximum catalytic activity. This is the temperature range where the enzyme's structure is most stable and its active site is perfectly shaped to bind to the substrate.

4. **Typical Optimum Temperature**: For most enzymes in the human body, the optimum temperature is around 37 degrees Celsius (98.6 degrees Fahrenheit). At this temperature, the enzyme functions efficiently and the reaction rate is at its peak.

5. **Effect of Temperature Changes**: If the temperature rises significantly above the optimum (for example, above 40 degrees Celsius), the enzyme may denature, meaning it loses its functional shape and, consequently, its catalytic activity. Conversely, at lower temperatures, the reaction rate may decrease as molecular movement slows down.

6. **Conclusion**: Therefore, an enzyme shows maximum catalytic activity at its optimum temperature, which is typically around 37 degrees Celsius for human enzymes.

### Final Answer:
An enzyme shows maximum catalytic activity at its optimum temperature.

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