Which one of the following vectors are used to deliver a deliver a desirable gene into animal and plant cells, respectively?

Options

A. Ti plasmid and retroviruses
B. retroviruses and Ti plasmid
C. bacteriophage and pBR322
D. pBR322 and bacteriophage

Answer

To answer the question regarding which vectors are used to deliver a desirable gene into animal and plant cells, we can break down the solution into clear steps:

### Step-by-Step Solution

1. **Understanding the Question**: The question asks for the specific vectors used to deliver genes into animal and plant cells. We need to identify these vectors correctly.

2. **Identifying the Vector for Plant Cells**:
- The most commonly used vector for delivering genes into plant cells is the **Agrobacterium tumefaciens** Ti plasmid.
- This plasmid has the ability to transfer a part of its DNA (T-DNA) into the plant genome, facilitating the integration of the desirable gene.

3. **Identifying the Vector for Animal Cells**:
- For animal cells, the most effective vector is **retroviruses**.
- Retroviruses can integrate their RNA into the host cell's DNA, often using an enzyme called reverse transcriptase to convert their RNA into DNA, which can then be integrated into the animal cell's genome.

4. **Conclusion**: Therefore, the vectors used to deliver a desirable gene into animal and plant cells are:
- **Plant Cells**: Ti plasmid from Agrobacterium
- **Animal Cells**: Retroviruses

### Final Answer
- **For Plant Cells**: Ti plasmid (from Agrobacterium)
- **For Animal Cells**: Retroviruses

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