The frist transgenic tobacco plant was resistant to the weedicide glyphosate. The gene for glyphosate resistance was derived from :

Options

A. A. E.coil
B. B. Bacillus thruingiensis
C. C. Salmonella typhimurium
D. D. Salmaonella hygroscopicus

Answer

To answer the question regarding the origin of the gene for glyphosate resistance in the first transgenic tobacco plant, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Transgenic Plants**: Transgenic plants are those that have been genetically modified to express a gene from another organism. This can confer various traits, such as resistance to herbicides.

2. **Identifying the First Transgenic Tobacco Plant**: The first transgenic tobacco plant was produced in 1982. This plant was engineered to be resistant to certain herbicides, specifically glyphosate.

3. **Researching Glyphosate Resistance**: Glyphosate is a widely used herbicide, and the development of resistant plants allows for effective weed control without harming the crop.

4. **Source of Glyphosate Resistance Gene**: The gene responsible for glyphosate resistance in the first transgenic tobacco plant was derived from a specific bacterium. The options provided are:
- E. coli
- Bacillus thuringiensis
- Salmonella damperium
- Salmonella hygroscopicus

5. **Identifying the Correct Bacterium**: The correct source of the glyphosate resistance gene is **Bacillus thuringiensis**. This bacterium produces a toxin (Bt toxin) that can provide resistance to various herbicides.

6. **Conclusion**: Therefore, the gene for glyphosate resistance in the first transgenic tobacco plant was derived from **Bacillus thuringiensis**.

### Final Answer:
The gene for glyphosate resistance in the first transgenic tobacco plant was derived from **Bacillus thuringiensis**.

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