BT COTTON

Options

A. kill insect pests
B. contain Cry II Ac
C. provide alkaline medium for prototoxin
D. affect the yield of cotton

Answer

**Step-by-Step Solution for the Question on BT Cotton:**

1. **Understanding BT Cotton**: BT Cotton is a genetically modified organism (GMO) that has been engineered to express a specific protein that helps in pest control. It is derived from the bacterium *Bacillus thuringiensis*.

2. **The Role of *Bacillus thuringiensis***: This bacterium contains a gene known as the cry gene, which produces a protein called Cry protein. This protein is toxic to certain insect pests.

3. **Mechanism of Action**: When insects feed on BT Cotton, they ingest the Cry protein. This protein acts on the gut of the insect, causing it to swell and eventually leading to the death of the insect.

4. **Evaluating the Options**:
- **Option A: It kills the insect pest** - This is correct. The primary purpose of BT Cotton is to kill insect pests that feed on it.
- **Option B: It contains cry2ac** - This is incorrect. BT Cotton contains the cry gene, but not specifically the cry2ac variant.
- **Option C: It provides an alkaline medium for the protoxin** - This is also incorrect. The mechanism does not involve providing an alkaline medium for the protoxin.
- **Option D: It affects the yield of the cotton** - This is misleading. While it can indirectly affect yield by reducing pest damage, its primary function is not to affect yield directly.

5. **Conclusion**: The correct answer to the question is **Option A**, as BT Cotton is specifically designed to kill insect pests.

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