Turn over number of an enzyme means

Options

A. number of substrate molecules acted upon by one molecule of an enzyme per second.
B. number of enzyme molecules acting on one molecule of substrate per mintue.
C. number of molecules of product produced by an enzyme in one minute.
D. number of subsrate molecules acted upon by an enzyme per second.

Answer

To answer the question regarding the turnover number of an enzyme, let's break it down step by step:

### Step-by-Step Solution:

1. **Understanding Turnover Number**:
- The turnover number (often denoted as \( k \)) refers to the maximum number of substrate molecules that one enzyme molecule can convert into product per unit of time.

2. **Analyzing the Options**:
- We need to evaluate the provided options to determine which one correctly defines the turnover number.
- The options are:
1. Number of substrate molecules acted upon by one molecule of an enzyme per second.
2. Number of enzyme molecules acting on one molecule of substrate per one minute.
3. Number of molecules of product produced by an enzyme in one minute.
4. Number of substrate molecules acted upon by the enzyme per second.

3. **Identifying the Correct Definition**:
- The turnover number specifically measures how many substrate molecules are converted into product by a single enzyme molecule in a given time frame.
- Therefore, the correct option must reflect this definition.

4. **Choosing the Right Option**:
- The first option states: "Number of substrate molecules acted upon by one molecule of an enzyme per second."
- This option accurately describes the turnover number as it focuses on the substrate molecules processed by a single enzyme molecule in a time frame of one second.

5. **Conclusion**:
- The turnover number of an enzyme means the number of substrate molecules acted upon by one molecule of an enzyme per second.

### Final Answer:
The turnover number of an enzyme means the number of substrate molecules acted upon by one molecule of an enzyme per second.

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