Hershey and Chase's experiment was based on the principle:

Options

A. Transformation
B. Translation
C. Transduction
D. Transcription

Explanation

**Step-by-Step Solution:**

1. **Identify the Experiment**: The question refers to the Hershey and Chase experiment, which was conducted by Alfred Hershey and Martha Chase in 1952.

2. **Understand the Purpose**: The primary aim of the Hershey and Chase experiment was to determine whether DNA or protein was the genetic material in viruses, specifically the T2 bacteriophage.

3. **Principle of the Experiment**: The principle underlying the Hershey and Chase experiment is based on the concept of transduction. Transduction is a process where foreign DNA is introduced into a cell via a viral vector.

4. **Experimental Design**: In their experiment, Hershey and Chase used radioactive isotopes to label DNA and protein separately. They used phosphorus-32 (³²P) to label DNA and sulfur-35 (³⁵S) to label protein.

5. **Results**: After allowing the labeled phages to infect bacterial cells, they found that only the phosphorus-labeled DNA entered the bacteria, while the sulfur-labeled protein remained outside. This indicated that DNA, not protein, was the genetic material.

6. **Conclusion**: The conclusion drawn from the experiment was that DNA is the genetic material responsible for heredity in organisms, confirming the principle of transduction.

**Final Answer**: The principle of the Hershey and Chase experiment was based on transduction.

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