Meaning of prefix Bt in Bt-cotton is

Options

A. Bacterial toxin
B. Biological toxin
C. Toxin released by Bacillus thuringiensis
D. Biotechnology

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the meaning of the prefix "Bt" in "Bt-cotton".

2. **Identifying the Context**: Bt-cotton is a genetically modified crop designed to be resistant to certain pests.

3. **Defining "Bt"**: The prefix "Bt" stands for "Bacillus thuringiensis", which is a type of bacteria.

4. **Function of Bacillus thuringiensis**: This bacterium produces proteins that are toxic to specific insects, such as caterpillars and beetles.

5. **Mechanism of Action**: The proteins produced by Bacillus thuringiensis are known as insecticidal proteins. When insects consume these proteins, they become active in the insect's gut, leading to the formation of pores in the gut wall, causing swelling and ultimately death of the insect.

6. **Conclusion**: Therefore, the correct interpretation of "Bt" in Bt-cotton is that it refers to the "toxin released by Bacillus thuringiensis".

**Final Answer**: The prefix "Bt" in Bt-cotton means "toxin released by Bacillus thuringiensis".

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