Who explained the operon model the first time

Options

A. Francois Jacob
B. Jacques Monod
C. Francois Jacob and Jacques Monod
D. Beadle & Tatum

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks who was the first person to explain the operon model.

2. **Defining Operon**: An operon is a cluster of genes under the control of a single promoter, which are transcribed together. The lac operon is a well-known example that regulates the metabolism of lactose in bacteria like E. coli.

3. **Identifying Key Scientists**: The operon model was first explained by two scientists: François Jacob and Jacques Monod.

4. **Context of Their Work**: Jacob and Monod conducted their research on the synthesis of the enzyme beta-galactosidase in E. coli, which is involved in lactose metabolism.

5. **Contribution to Genetics**: Their work laid the foundation for understanding gene regulation and expression in prokaryotes, which was a significant advancement in molecular biology.

6. **Conclusion**: Therefore, the correct answer to the question is that the operon model was first explained by François Jacob and Jacques Monod.

**Final Answer**: François Jacob and Jacques Monod.

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