Which of the following isotopes were used in the Hershey-Chase experiments ?

Options

A. `.^(32)S,.^(30)P`
B. `.^(31)S,.^(29)P`
C. `.^(35)S,.^(32)P`
D. `.^(34)S,.^(33)P`

Answer

To solve the question regarding the isotopes used in the Hershey-Chase experiments, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Hershey-Chase Experiment**:
- The Hershey-Chase experiment was conducted by Alfred Hershey and Martha Chase to determine whether DNA or protein was the genetic material in bacteriophages (viruses that infect bacteria).

2. **Identify the Isotopes Used**:
- In the experiment, they used radioactive isotopes to label DNA and proteins. DNA contains phosphorus, while proteins contain sulfur.

3. **Select the Correct Isotopes**:
- They used:
- **Phosphorus-32 (P-32)** to label DNA, as DNA contains phosphorus.
- **Sulfur-35 (S-35)** to label proteins, as proteins contain sulfur.

4. **Evaluate the Options**:
- Given options:
1. Sulfur-32 and Phosphorus-30 (Incorrect)
2. Sulfur-31 and Phosphorus-29 (Incorrect)
3. Sulfur-35 and Phosphorus-32 (Correct)
4. Sulfur-34 and Phosphorus-33 (Incorrect)

5. **Conclusion**:
- The correct answer is **Sulfur-35 and Phosphorus-32**, which corresponds to option 3.

### Final Answer:
The isotopes used in the Hershey-Chase experiments were **Sulfur-35 and Phosphorus-32**.

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