Which of the following is required for micro-injection method of gene transfer ?

Options

A. 1) micro-particles
B. 2) Micro-pipettes
C. 3) Divalent cations
D. 4) UV radiations

Explanation

To answer the question "Which of the following is required for micro-injection method of gene transfer?", we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Micro-injection Method**:
- Micro-injection is a technique used to transfer genetic material (like recombinant DNA) directly into the nucleus of a cell. This method is often utilized in genetic engineering and research.

2. **Identify the Tools Used in Micro-injection**:
- The primary tool used in the micro-injection method is a micropipette. This is a very fine pipette that allows for precise injection of small volumes of liquid, including DNA.

3. **Evaluate the Options**:
- **Option 1: Microparticles** - These are not specifically required for the micro-injection method.
- **Option 2: Micropipettes** - This is the correct tool used for injecting DNA into cells.
- **Option 3: Divalent cations** - While they can be used in other methods of gene transfer, they are not specifically required for micro-injection.
- **Option 4: UV radiation** - This is not a requirement for the micro-injection method.

4. **Conclude the Correct Answer**:
- Based on the evaluation, the correct answer is **Option 2: Micropipettes**.

### Final Answer:
The correct answer is **Option 2: Micropipettes**.

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