What is true of Bt toxin?

Options

A. The concerned bacillus has antitoxins
B. The inactive protoxin gets converted into active form in the insect gut
C. Bt protein exists as active toxin in the Bacillus
D. The activated toxin enters the ovaries of the pest sterilize it and thus prevents its multiplication

Answer

**Step-by-Step Solution:**

1. **Understanding Bt Toxin**: Bt toxin is a toxic protein produced by the bacterium Bacillus thuringiensis. It is known for its insecticidal properties.

2. **Formation of Protoxin**: In the life cycle of Bacillus thuringiensis, it produces protein crystals that are initially in an inactive form known as protoxin.

3. **Activation in Insect Gut**: When insects ingest the protoxin, it enters their gut, which has an alkaline pH (around 10). This alkaline environment is crucial for the conversion of the protoxin into its active form.

4. **Mechanism of Action**: Once activated in the gut, the Bt toxin binds to specific receptors in the gut lining of the insect, leading to the disruption of the gut cells, which ultimately kills the insect.

5. **Correct Statement**: Among the options provided, the statement that is true regarding Bt toxin is: "The inactive protoxin gets converted into active form in the insect gut."

**Final Answer**: The correct statement about Bt toxin is that "The inactive protoxin gets converted into active form in the insect gut."

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