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

To solve the question about the proteins that control cotton bollworms, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Context**:
- Cotton bollworms are pests that affect cotton crops. To manage these pests, certain proteins produced by specific genes are utilized.

2. **Identify the Relevant Bacteria**:
- The bacteria involved in controlling cotton bollworms is *Bacillus thuringiensis* (Bt). This bacterium produces a toxin known as Bt toxin, which is insecticidal.

3. **Learn About the Bt Toxin**:
- The Bt toxin is effective against various insects, including cotton bollworms. When ingested by the insect, the toxin is activated in the gut, leading to cell lysis and ultimately the death of the insect.

4. **Identify the Cry Genes**:
- The proteins that code for the Bt toxin are controlled by specific genes known as cry genes. The main cry genes relevant to cotton bollworms are:
- **Cry1AC**
- **Cry2AB**

5. **Analyze the Options**:
- The question provides several options regarding which proteins control cotton bollworms:
- Cry1AC
- Cry1AB
- Cry2AB
- Combinations of these genes.

6. **Determine the Correct Proteins**:
- From the information:
- **Cry1AC** and **Cry2AB** are effective against cotton bollworms.
- **Cry1AB** is effective against corn borers, not cotton bollworms.

7. **Select the Correct Answer**:
- Based on the analysis, the correct proteins that control cotton bollworms are those coded by **Cry1AC** and **Cry2AB**.

### Final Answer:
The proteins that control cotton bollworms are coded by **Cry1AC and Cry2AB**.

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