The Ti plasmid, is often used for making transgenic plants. This plasmid is found in

Options

A. Rhizobium of the roots of leguminous plants
B. Agrobacterium
C. Yeast as a 2 `mu`m plasmid
D. Azotobacter

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks about the Ti plasmid, which is commonly used in the creation of transgenic plants. We need to identify the organism in which this plasmid is found.

2. **Identifying the Options:**
The options provided are:
- A) Rhizobium of the roots of leguminous plants
- B) Agrobacterium
- C) Yeast (2-mu plasmid)
- D) Azotobacter

3. **Analyzing Each Option:**
- **A) Rhizobium:** This is a genus of bacteria that forms symbiotic relationships with leguminous plants, primarily involved in nitrogen fixation. It does not carry the Ti plasmid.
- **B) Agrobacterium:** This is a soil bacterium known for its ability to transfer DNA to plant cells, specifically through the Ti plasmid, which induces tumor formation in plants.
- **C) Yeast (2-mu plasmid):** Yeast is a eukaryotic organism that does not utilize the Ti plasmid for genetic engineering.
- **D) Azotobacter:** This is an aerobic soil bacterium involved in nitrogen fixation but does not carry the Ti plasmid.

4. **Conclusion:**
Based on the analysis, the correct answer is **B) Agrobacterium**, as it is the organism that contains the Ti plasmid and is used in the genetic engineering of plants.

5. **Final Answer:**
The Ti plasmid is found in **Agrobacterium**.

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