Mark the incorrect option w.r.t lac operon

Options

A. Is under positive as well as negative control
B. Controls catabolic pathway
C. Shows feed back repression
D. Discovered by jacob and Monod

Answer

To solve the question regarding the incorrect option with respect to the lac operon, let's analyze the statements provided in the question step by step.

### Step-by-Step Solution:

1. **Understanding the Lac Operon**: The lac operon is a set of genes in E. coli that are involved in the metabolism of lactose. It is regulated by both positive and negative controls.

2. **Identifying the Options**: The options given include:
- Under positive as well as negative control
- Control catabolic pathway
- Show feedback repression
- Discovered by Jacob and Monod

3. **Analyzing Each Option**:
- **Option 1**: "Under positive as well as negative control" - This is true. The lac operon is indeed regulated by both types of control.
- **Option 2**: "Control catabolic pathway" - This is also true, as the lac operon is involved in the catabolism of lactose.
- **Option 3**: "Show feedback repression" - This is incorrect. The lac operon does not exhibit feedback repression. Instead, it is regulated through other mechanisms.
- **Option 4**: "Discovered by Jacob and Monod" - This statement is true, as the lac operon was discovered by François Jacob and Jacques Monod.

4. **Conclusion**: The incorrect option regarding the lac operon is **Option 3: "Show feedback repression"**.

### Final Answer:
The incorrect option with respect to the lac operon is **Option 3: Show feedback repression**.

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