Pick up the incorrect statement 

Options

A. a. The rate enzyme catalyzed reaction also depends upon enzyme concentration
B. b. The rate of enzyme catalyzed reaction depends upon ionic strength
C. c. The rate of enzyme catalyzed reaction first increases with temperature and then decreases after attaining optimum temperature
D. d. The increase in activity of protein as enzyme is due to denaturation

Answer

To solve the question of identifying the incorrect statement regarding enzyme-catalyzed reactions, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement A**: "The rate of enzyme catalyzed reaction also depends upon enzyme concentration."
- **Analysis**: This statement is true. The rate of an enzyme-catalyzed reaction increases with an increase in enzyme concentration, as more enzyme molecules are available to catalyze the reaction.

2. **Statement B**: "The rate of enzyme catalyzed reaction depends upon ionic strength."
- **Analysis**: This statement is also true. Ionic strength can affect the interactions between enzymes and substrates, influencing the rate of the reaction.

3. **Statement C**: "The rate of enzyme catalyzed reaction first increases with the temperature and then decreases after attaining an optimum temperature."
- **Analysis**: This statement is true as well. Enzyme activity typically increases with temperature up to a certain point (optimum temperature), after which the activity decreases due to denaturation of the enzyme.

4. **Statement D**: "The increase in activity of protein as an enzyme is due to denaturation."
- **Analysis**: This statement is incorrect. Denaturation of proteins leads to the loss of their three-dimensional structure, which is essential for their activity as enzymes. Therefore, denaturation actually decreases enzyme activity, not increases it.

### Conclusion:
The incorrect statement is **Statement D**: "The increase in activity of protein as an enzyme is due to denaturation."

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