Lock & Key model of enzyme action was proposed by

Options

A. Paul Fields
B. D.D. Woods
C. Emil Fischer
D. Koshland

Answer

To answer the question regarding who proposed the Lock & Key model of enzyme action, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks who proposed the Lock & Key model of enzyme action. This model describes how enzymes and substrates interact.

2. **Identify the Options**: The options provided are:
- A) Paul Field
- B) Dee Dee Woods
- C) Emil Fisher
- D) Coach Land

3. **Recall the Models of Enzyme Action**: There are two main theories regarding enzyme action:
- The **Lock and Key model**, which suggests that the enzyme's active site (the 'lock') is a perfect fit for the substrate (the 'key').
- The **Induced Fit model**, which is a refinement of the Lock and Key model.

4. **Match the Model to the Scientist**: The Lock and Key model was proposed by **Emil Fisher**. The Induced Fit model was later proposed by **Daniel Koshland**.

5. **Select the Correct Answer**: Based on the information, the correct answer to the question is **C) Emil Fisher**.

### Final Answer:
The Lock & Key model of enzyme action was proposed by **Emil Fisher**.

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