Which one of the following is not a protein ?

Options

A. Wool
B. Nail
C. Hair
D. DNA

Answer

To determine which of the following options is not a protein, we need to analyze each option provided:

1. **Wool**: Wool is primarily composed of a protein called alpha keratin. Alpha keratin is a fibrous protein that serves as a structural component in various biological materials.

2. **Nail**: Nails are also made up of alpha keratin. Like wool, nails are structural parts of the body and consist of this protein.

3. **Hair**: Hair is similarly composed of alpha keratin. It is another structural component of the body, made up of the same protein as wool and nails.

4. **DNA**: DNA (deoxyribonucleic acid) is a nucleic acid, not a protein. It serves as the genetic material in living organisms and is responsible for the transmission of genetic information.

Now, let's summarize the findings:

- Wool, nails, and hair are all composed of alpha keratin, which is a type of protein.
- DNA is a nucleic acid and does not fall under the category of proteins.

**Conclusion**: The option that is not a protein is **DNA**.

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