if it is wanted to have `T_(2)` bacteriophages with protein cover labelled with `.^(35)S`, it is desirable to

Options

A. grow bacteriophages in medium containing `^(35)S` labelled amino acids
B. introduce `T_(2)` in bacterium having `.^(35)S` labelled protein
C. obtain a single phage with `.^(35)S` labelled protein and allow it to multiply
D. all are correct

Answer

To obtain T2 bacteriophages with a protein coat labeled with radioactive sulfur (35S), follow these steps:

### Step-by-Step Solution:

1. **Understand the Composition of T2 Bacteriophages**:
- T2 bacteriophages consist of a protein coat (capsid) and genetic material (DNA). The protein coat is what we want to label with 35S.

2. **Identify the Requirement for Labeling**:
- To label the protein coat with 35S, we need to provide a source of amino acids that are labeled with this radioactive isotope. Proteins are made up of amino acids, and the bacteriophage will use these amino acids to synthesize its protein coat.

3. **Prepare the Growth Medium**:
- The growth medium must contain amino acids that are specifically labeled with 35S. This means we need to use a culture medium that has been supplemented with 35S-labeled amino acids.

4. **Inoculate the Medium with T2 Bacteriophages**:
- Introduce the T2 bacteriophages into the prepared medium containing the 35S-labeled amino acids. As the bacteriophages replicate, they will incorporate the labeled amino acids into their protein coats.

5. **Harvest the Bacteriophages**:
- After allowing sufficient time for the bacteriophages to replicate, harvest the newly formed T2 bacteriophages. These will now have protein coats labeled with 35S.

6. **Verification**:
- Finally, verify that the bacteriophages have the desired radioactive label on their protein coat, which can be done using techniques such as autoradiography or scintillation counting.

### Conclusion:
The correct approach to obtain T2 bacteriophages with a protein coat labeled with 35S is to grow them in a medium containing 35S-labeled amino acids.

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