The vector for T-DNA is :

Options

A. Thermus aquaticus
B. Salmonella typhimurium
C. Agrobacterium tumefaciens
D. Escherichia coli

Answer

**Step-by-Step Text Solution:**

1. **Understanding T-DNA**: T-DNA stands for Transfer DNA. It is a segment of DNA that is transferred from the bacterium Agrobacterium tumefaciens into the genome of a host plant cell. This transfer can lead to the formation of tumors in the plant.

2. **Identifying the Source of T-DNA**: The T-DNA is specifically associated with Agrobacterium tumefaciens, a bacterium known for its ability to transfer T-DNA to plant cells, causing tumor formation.

3. **Evaluating the Options**:
- **Thermus Aquaticus**: This is a bacterium used in PCR (Polymerase Chain Reaction) for its heat-stable DNA polymerase. It is not related to T-DNA transfer.
- **Salmonella Typhimurium**: This bacterium is known for causing foodborne illnesses and is not involved in T-DNA transfer.
- **Agrobacterium Tumefaciens**: This is the correct answer as it is the bacterium that carries T-DNA and facilitates its transfer to plant cells.
- **E. coli**: While E. coli is a common bacterium used in molecular biology, it is not associated with T-DNA transfer.

4. **Conclusion**: Based on the evaluation of the options, the vector for T-DNA is Agrobacterium tumefaciens.

**Final Answer**: The vector for T-DNA is Agrobacterium tumefaciens.

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