Cotton bollworms are controlled by certain proteins that are coded by

Options

A. crylAc.
B. crylAb and cryllAb.
C. crylAb and crylAc.
D. crylAb and crylAc.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the proteins that control cotton bollworms and the genes that code for these proteins.

2. **Identifying the Source**: The proteins that control cotton bollworms are derived from the bacterium *Bacillus thuringiensis* (Bt). This bacterium produces insecticidal proteins.

3. **Identifying the Proteins**: The specific proteins mentioned in the transcript are Cry1AC, Cry1AB, and Cry2AB. These proteins are known to be effective against various insects, including cotton bollworms.

4. **Understanding the Mechanism**: The proteins produced by *Bacillus thuringiensis* are initially inactive when produced by the bacteria. Once ingested by the target insects, they become active and form pores in the insect's gut cells, leading to cell swelling and ultimately the death of the insect.

5. **Identifying the Gene**: The gene that codes for these insecticidal proteins is referred to as the cry gene. This gene can be isolated from *Bacillus thuringiensis* and introduced into crops to provide them with resistance against pests like the cotton bollworm.

6. **Conclusion**: The proteins that control cotton bollworms are coded by the cry genes, specifically Cry1AC and Cry1AB.

**Final Answer**: The proteins that control cotton bollworms are coded by the cry genes, specifically Cry1AC and Cry1AB.

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