Prions are viruses that have only

Options

A. protein coat and no nucleic acid
B. core of nucleic acid
C. lipoprotein coat
D. few genes

Answer

**Step-by-Step Solution:**

1. **Understanding Prions**: Begin by defining what prions are. Prions are infectious agents that are smaller than viruses and are solely composed of proteins.

2. **Composition of Prions**: Highlight that prions do not contain any nucleic acids, meaning they lack both DNA and RNA. This is a key characteristic that differentiates them from traditional viruses.

3. **Replication Mechanism**: Explain that prions are capable of replicating without nucleic acids. They induce abnormal folding of normal cellular proteins, which are referred to as prion proteins.

4. **Function of Prions**: Discuss the role of prions in causing diseases. They are abnormal pathogenic agents that can lead to neurodegenerative diseases by inducing the misfolding of normal proteins in the brain.

5. **Analyzing Options**: Now, look at the options provided in the question:
- Option A: Protein coat and no nucleic acid (Correct)
- Option B: Core of nucleic acid (Incorrect, as prions do not have nucleic acids)
- Option C: Lipoprotein coat (Incorrect, prions do not have a lipoprotein coat)
- Option D: Fugenes (Incorrect, this term does not relate to prions)

6. **Conclusion**: Based on the analysis, the correct answer is that prions are viruses that have only a protein coat and no nucleic acid.

**Final Answer**: Prions are viruses that have only a protein coat and no nucleic acid.

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