In r-DNA technique which of the following technique is not used in introducing DNA into host cell

Options

A. Transduction
B. Conjugation
C. Transformation
D. Electroporation

Answer

**Step-by-Step Solution:**

1. **Understanding r-DNA Technique**: The recombinant DNA (r-DNA) technique involves combining DNA from different sources. A crucial part of this process is introducing the recombinant DNA into a host cell.

2. **Identifying Methods of DNA Introduction**: There are several methods used to introduce DNA into host cells, including:
- **Transduction**: This method uses viruses to transfer DNA from one organism to another.
- **Conjugation**: This is a process of sexual reproduction in bacteria where genetic material is exchanged between two bacterial cells.
- **Transformation**: This involves the uptake of naked DNA by a bacterial cell, leading to a change in its genotype.

3. **Evaluating the Options**: The question asks which of the listed techniques is NOT used to introduce DNA into a host cell.
- **Electroporation**: This is a method that uses an electric field to increase the permeability of the cell membrane, allowing DNA to enter the cell.

4. **Identifying the Incorrect Option**: Among the methods listed, transformation is the one that does not involve the introduction of DNA into a host cell in the context of r-DNA technology. Instead, it refers to the natural uptake of DNA by bacteria, which is not a method used in the r-DNA technique.

5. **Conclusion**: Therefore, the correct answer to the question is that transformation is not used in the r-DNA technique for introducing DNA into host cells.

**Final Answer**: Option number three (Transformation) is not used in introducing DNA into the host cell in the r-DNA technique.

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