How does the rate of an enzyme-catalyzed reactions vary with `(a)` temprature and `(b)` `pH?` Represent diagrammatically.

Explanation

### Step-by-Step Solution:

**(a) Variation of Enzyme-Catalyzed Reaction Rate with Temperature:**

1. **Initial Increase:** At low temperatures, the rate of enzyme-catalyzed reactions increases as the temperature rises. This is because higher temperatures provide more kinetic energy to the molecules, leading to more frequent collisions between the enzyme and substrate.

2. **Optimal Temperature:** The enzyme activity reaches its maximum at an optimal temperature, which is typically around 37 degrees Celsius for many human enzymes. At this temperature, the enzyme's structure is ideal for binding the substrate, and the reaction rate is at its peak.

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