Amongst the following, which characteristic feature is not applicable to Bt cotton?

Options

A. Bt is the abbreviated term for botulinum toxin.
B. Such cotton is resistant to armyworms and beetles.
C. The toxin is activated in the body of the insect.
D. The toxin is coded by a gene called"cry".

Answer

**Step-by-Step Solution:**

1. **Understand Bt Cotton**: Bt cotton is a genetically modified organism (GMO) that has been engineered to be resistant to certain pests. The "Bt" stands for Bacillus thuringiensis, a bacterium that produces proteins toxic to specific insects.

2. **Identify the Features of Bt Cotton**: The key features of Bt cotton include:
- It is pest-resistant due to the incorporation of genes from Bacillus thuringiensis.
- The genes responsible for pest resistance are known as cry genes (e.g., cry1, cry2, cry3).
- The toxin produced by these genes is activated in the gut of the insect, leading to the insect's death.

3. **Analyze the Options**: The question asks for a characteristic feature that is NOT applicable to Bt cotton. The options typically include:
- A. Bt is an abbreviation for botulinum toxin.
- B. Bt cotton is resistant to armyworms and beetles.
- C. The toxin is activated in the body of the insect.
- D. The toxin is coded by the gene called cry.

4. **Evaluate Each Option**:
- **Option A**: "Bt is an abbreviation for botulinum toxin." This is incorrect because "Bt" refers to Bacillus thuringiensis, not botulinum toxin, which is produced by Clostridium botulinum.
- **Option B**: "Bt cotton is resistant to armyworms and beetles." This is correct as Bt cotton is designed to be resistant to these pests.
- **Option C**: "The toxin is activated in the body of the insect." This is also correct; the toxin becomes active in the gut of the insect.
- **Option D**: "The toxin is coded by the gene called cry." This is correct as the cry genes are responsible for producing the toxin.

5. **Conclusion**: The characteristic feature that is NOT applicable to Bt cotton is **Option A**: "Bt is an abbreviation for botulinum toxin."

**Final Answer**: Option A: "Bt is an abbreviation for botulinum toxin."

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