Chilled ethyl alcohol is used during DNA technology for

Options

A. Precipitation of histones
B. Precipitation of DNA
C. Removal of enzymes
D. Precipitation of cell fragments .

Answer

To solve the question "Chilled ethyl alcohol is used during DNA technology for," we need to analyze the options provided and understand the role of chilled ethyl alcohol in DNA technology.

### Step-by-Step Solution:

1. **Understanding the Purpose of Chilled Ethyl Alcohol**:
- Chilled ethyl alcohol (ethanol) is commonly used in molecular biology, particularly in the process of DNA extraction and purification.

2. **Evaluating the Options**:
- **Option 1: Precipitation of Histones**:
- This option is incorrect. Histones can be precipitated using a phenol-chloroform mixture, not chilled ethyl alcohol.

- **Option 2: Precipitation of DNA**:
- This is the correct option. Chilled ethyl alcohol is used to precipitate DNA from a solution. When DNA is mixed with chilled alcohol, it becomes insoluble and precipitates out of the solution, allowing for its collection.

- **Option 3: Removal of Enzymes**:
- This option is incorrect. While chilled alcohol may help stabilize DNA, it does not directly remove enzymes.

- **Option 4: Precipitation of Cell Fragments**:
- This option is also incorrect. Chilled ethyl alcohol is not primarily used for precipitating cell fragments.

3. **Conclusion**:
- Based on the analysis, the correct answer is **Option 2: Precipitation of DNA**. Chilled ethyl alcohol is effective in precipitating DNA due to its low temperature, which reduces the activity of enzymes that could degrade the DNA.

### Final Answer:
Chilled ethyl alcohol is used during DNA technology for **Precipitation of DNA**.