The experiments that proved the DNA in chromosomes also replicate semiconservatively were conducted by

Options

A. Hershey and Chase
B. Meselson and Stahl
C. Avery etal
D. Griffith

Answer

To answer the question about which scientists conducted experiments that proved DNA in chromosomes replicates semiconservatively, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Semiconservative Replication**:
- Semiconservative replication refers to the process by which DNA makes a copy of itself. In this process, each of the two new DNA molecules contains one original strand and one newly synthesized strand.

2. **Identify Key Experiments**:
- The experiments that demonstrated the semiconservative nature of DNA replication were crucial in molecular biology.

3. **Recall the Scientists Involved**:
- The key scientists who conducted these experiments were Matthew Meselson and Franklin Stahl. They performed their famous experiment in 1958.

4. **Describe the Experiment**:
- Meselson and Stahl used a bacterium called E. coli and a technique involving heavy nitrogen (N-15) and light nitrogen (N-14) to trace the replication of DNA. They showed that after one round of replication, the DNA consisted of one heavy strand and one light strand, confirming semiconservative replication.

5. **Evaluate the Options**:
- Given the options:
- A) Hershey and Chase
- B) Meselson and Stahl
- C) Avery et al.
- D) Dripping
- We can eliminate options A, C, and D as they are not associated with the discovery of semiconservative replication.

6. **Select the Correct Answer**:
- The correct answer is **Option B: Meselson and Stahl**.

### Final Answer:
The experiments that proved the DNA in chromosomes also replicate semiconservatively were conducted by **Meselson and Stahl**.

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