The transfer of genetic material from one bacterial cell to another bacterial cell with the help of a bacteriophage was dicovered by laderberg and Zinder. It is known as

Options

A. Mutation
B. transformation
C. transduction
D. gene flow

Answer

To solve the question regarding the transfer of genetic material from one bacterial cell to another with the help of a bacteriophage, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks about a specific method of genetic transfer between bacterial cells facilitated by bacteriophages, as discovered by Lederberg and Zinder.

2. **Identify the Options**: The options provided are:
- Mutation
- Transformation
- Transduction
- Gene flow

3. **Analyze Each Option**:
- **Mutation**: This refers to a change in the DNA sequence. It does not involve the transfer of genetic material between cells. Therefore, this option is not correct.

- **Transformation**: This is a process where a bacterial cell takes up foreign DNA from its environment. It does not involve bacteriophages. Thus, this option is also incorrect.

- **Transduction**: This is the process where genetic material is transferred from one bacterial cell to another via bacteriophages. This method was indeed discovered by Lederberg and Zinder in 1951. Therefore, this option is correct.

- **Gene Flow**: This term refers to the transfer of genetic material between populations, not specifically between bacterial cells. Hence, this option is not applicable to the question.

4. **Conclusion**: Based on the analysis, the correct answer is **Transduction**, as it specifically involves the transfer of genetic material between bacterial cells with the help of bacteriophages.

### Final Answer:
The transfer of genetic material from one bacterial cell to another bacterial cell with the help of a bacteriophage, discovered by Lederberg and Zinder, is known as **Transduction**.

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