In experiment to study fermentation by yeast, temperature was increased from `20^(@)`C to `30^(@)`C, rate of enzyme catalysed reaction increases by

Options

A. 2 times
B. 5 times
C. 10 times
D. No effect

Answer

To solve the question regarding the effect of temperature on the rate of enzyme-catalyzed reactions during yeast fermentation, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Context**: The experiment involves studying fermentation by yeast, which is facilitated by enzymes. The question specifically asks about the effect of increasing temperature from 20°C to 30°C on the rate of the enzyme-catalyzed reaction.

2. **Temperature and Enzyme Activity**: Enzymes have an optimal temperature range where their activity is maximized. Generally, as the temperature increases, the kinetic energy of molecules increases, leading to more frequent collisions between enzymes and substrates, thus increasing the reaction rate.

3. **Identifying the Temperature Change**: The temperature is increased from 20°C to 30°C, which is a change of 10°C.

4. **Effect of Temperature Change on Reaction Rate**: It is known that for many enzymes, the rate of reaction approximately doubles with every 10°C increase in temperature, up to a certain point (the optimum temperature). Beyond this point, further increases in temperature can lead to denaturation of the enzyme.

5. **Conclusion**: Since the temperature is increased by 10°C, we can conclude that the rate of the enzyme-catalyzed reaction will double. Therefore, the correct answer is that the rate of reaction increases by 2 times.

### Final Answer:
The rate of enzyme-catalyzed reaction increases by **2 times** when the temperature is increased from 20°C to 30°C.

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