To deliver desirable genes into animals cell , one of the following vectors are commonly used .

Options

A. Ti plasmid of Agrobacterium tumifacies
B. Disarmed parthogenic organisms
C. 1 and 2
D. None of these

Answer

To deliver desirable genes into animal cells, the commonly used vector is a disarmed pathogenic organism, particularly retroviruses. Here’s a step-by-step breakdown of the solution:

### Step-by-Step Solution:

1. **Understanding Vectors**: Vectors are tools used in biotechnology to introduce foreign genetic material into a host organism. They can be plasmids, viruses, or other methods that facilitate gene transfer.

2. **Identifying the Context**: The question specifically asks about delivering genes into animal cells. It’s important to differentiate between vectors used for plants and those used for animals.

3. **Analyzing the Options**:
- **T.I. plasmid of Agrobacterium tumefaciens**: This vector is primarily used for plants, not animals. It is involved in transferring genes into plant cells.
- **Disarmed Pathogenic Organism**: This refers to modified pathogens, such as retroviruses, that have been altered so they cannot cause disease but can still deliver genetic material into animal cells.
- **First and Second**: This option is unclear without context, but it seems to imply multiple choices.
- **None of These**: This option suggests that none of the provided vectors are suitable, which is incorrect since disarmed pathogenic organisms are indeed used.

4. **Conclusion**: The most suitable vector for delivering desirable genes into animal cells is the disarmed pathogenic organism, specifically retroviruses. These viruses can integrate their genetic material into the host genome, making them effective for gene therapy applications.

### Final Answer:
The correct answer is **Disarmed Pathogenic Organism**.

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