Enzymes work at optimum temperature. Over a range `0-40^(@)C`, what would happen to the rate of enzyme controlled reactions for every `10^(@)C` rise in temperature ?

Options

A. The rate doubles itself
B. Decreases by half
C. No effect
D. First increases than decreases

Answer

To answer the question regarding the effect of temperature on the rate of enzyme-controlled reactions, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Enzymes**: Enzymes are biological catalysts that speed up chemical reactions in living organisms. They are sensitive to temperature changes.

2. **Optimum Temperature**: Each enzyme has an optimum temperature at which it functions most efficiently. This temperature allows the enzyme to have peak activity.

3. **Temperature Range**: The question specifies a temperature range of 0 to 40 degrees Celsius. As the temperature increases within this range, the activity of the enzyme also increases.

4. **Rate of Reaction**: Generally, for many enzymes, the rate of reaction approximately doubles with every 10 degrees Celsius increase in temperature, up to a certain point (the optimum temperature).

5. **Graphical Representation**: If we were to plot a graph of enzyme activity against temperature, we would see an initial increase in the rate of reaction with rising temperature, reaching a peak at the optimum temperature, and then a decline as the temperature continues to rise beyond this point.

6. **Conclusion**: Therefore, for every 10 degrees Celsius rise in temperature from 0 to 40 degrees Celsius, the rate of enzyme-controlled reactions would approximately double until the optimum temperature is reached.

### Final Answer:
The rate of enzyme-controlled reactions would double for every 10 degrees Celsius rise in temperature, up to the optimum temperature.

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