Which of the following statement is incorrect about viruses ?

Options

A. Viruses contain either RNA or DNA
B. Viruses do not have their own metabolic
C. Bacteriophages are usually double stranded DNA viruses
D. TMV contains both RNA and DNA as their genetic material

Answer

To determine which statement about viruses is incorrect, we will analyze each statement one by one based on our understanding of viruses.

### Step-by-Step Solution:

1. **Understanding the Nature of Viruses**:
- Viruses are non-cellular entities that require a host to replicate and carry out metabolic activities. They consist of genetic material (either DNA or RNA) enclosed in a protein coat.

2. **Analyzing the Statements**:
- **Statement 1**: "Viruses contain either DNA or RNA."
- This statement is correct. Viruses can have either DNA or RNA as their genetic material, but not both.

- **Statement 2**: "Viruses do not have their own metabolic activities."
- This statement is also correct. Viruses do not possess metabolic machinery and rely on a host cell for replication and metabolic processes.

- **Statement 3**: "Bacteriophages are usually double-stranded DNA viruses."
- This statement is correct as well. Bacteriophages, which are viruses that infect bacteria, often have double-stranded DNA.

- **Statement 4**: "TMV contains both RNA and DNA as their genetic material."
- This statement is incorrect. TMV (Tobacco Mosaic Virus) contains only RNA as its genetic material, not both DNA and RNA.

3. **Conclusion**:
- The incorrect statement about viruses is **Statement 4**: "TMV contains both RNA and DNA as their genetic material."

### Final Answer:
The incorrect statement about viruses is: **"TMV contains both RNA and DNA as their genetic material."**

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