The technique in which foregin DNA is precipitated over surface of metal particles for passing into target cells is

Options

A. microinjection
B. chemical-mediated gene transfer
C. particle gun
D. electroporation

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for a technique that involves the precipitation of foreign DNA onto the surface of metal particles for the purpose of transferring it into target cells.

2. **Identifying Vectorless Methods**: The techniques mentioned in the question are part of vectorless methods, which means they do not use a biological vector (like a virus or plasmid) to introduce DNA into cells.

3. **Exploring Different Techniques**: The transcript mentions several techniques:
- Microinjection: Direct injection of DNA into the nucleus of a cell.
- Chemical-mediated gene transfer: Using chemicals to facilitate DNA entry into cells.
- Electroporation: Applying an electric field to increase cell membrane permeability.
- Particle gun (also known as biolistics): This method involves coating metal particles (often gold) with DNA and then bombarding them into target cells.

4. **Focusing on the Particle Gun**: The technique that specifically involves precipitating foreign DNA onto the surface of metal particles (like gold) and then using a device to shoot these particles into cells is known as the "particle gun" method.

5. **Conclusion**: Therefore, the technique in which foreign DNA is precipitated over the surface of metal particles for passing into target cells is called the **particle gun**.

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