The Bt gene is isolated from the organism called :

Options

A. Brassica napus
B. Rhizobium
C. Azolla
D. Bacillus thuringiensis

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: The question asks about the source of the Bt gene. The Bt gene is known for its role in producing a specific toxin that is effective against certain insects.

2. **Recognize the Source**: The Bt gene is isolated from a bacterium. The specific bacterium known for producing this gene is called Bacillus thuringiensis.

3. **Understand the Function**: Bacillus thuringiensis produces a protein known as Bt toxin. This toxin is activated in the alkaline environment of the insect's gut, leading to the formation of pores in the gut cells, causing the cells to swell and eventually burst, which results in the death of the insect.

4. **Eliminate Incorrect Options**: The question may provide multiple-choice options. It is important to eliminate options that do not correspond to the correct organism. For example, Rhizobium and Azolla are not sources of the Bt gene.

5. **Conclude the Answer**: The correct answer to the question is that the Bt gene is isolated from Bacillus thuringiensis.

**Final Answer**: The Bt gene is isolated from the organism called Bacillus thuringiensis.

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