Which of the following is the function of enzyme?
I.Enzymes hold the substrate for a chemical reaction
II.It increase energy of activation.
III.It provide functional groups and carry out chemical reaction
Choose the correct option

Options

A. I and II are true
B. II and III are false
C. I and III are true
D. all are true

Answer

To solve the question regarding the functions of enzymes, we will analyze each statement provided and determine its validity based on our understanding of enzymes.

### Step-by-Step Solution:

1. **Understanding Enzymes**: Enzymes are biological catalysts that speed up chemical reactions by lowering the activation energy required for the reaction to occur. They are crucial in various biological processes.

2. **Evaluating Statement I**:
- **Statement I**: "Enzymes hold the substrate for a chemical reaction."
- **Analysis**: This statement is true. Enzymes bind to substrates, forming an enzyme-substrate complex, which facilitates the chemical reaction.

3. **Evaluating Statement II**:
- **Statement II**: "It increases energy of activation."
- **Analysis**: This statement is false. Enzymes actually lower the energy of activation, making it easier for reactions to occur.

4. **Evaluating Statement III**:
- **Statement III**: "It provides functional groups and carry out chemical reaction."
- **Analysis**: This statement is true. Enzymes often provide functional groups that participate in the reaction, thus facilitating the conversion of substrates into products.

5. **Conclusion**:
- From the analysis, we find that:
- Statement I is true.
- Statement II is false.
- Statement III is true.
- Therefore, the correct option is that statements I and III are true.

### Final Answer:
The correct option is **Option 3: 1 and 3 are true**.

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