TMV is

Options

A. ds Ribovirus
B. ds Deoxyvirus
C. ss Ribovirus
D. Ribovirus with 6400 capsomeres

Answer

**Step-by-Step Solution:**

1. **Identify TMV**: TMV stands for Tobacco Mosaic Virus. It is important to recognize what TMV refers to in the context of biological classification.

2. **Classification of TMV**: TMV is classified as a virus that specifically affects plants, making it a phytopathogen. This means it is a pathogen that causes diseases in plants.

3. **Disease Caused by TMV**: The virus is known to cause the tobacco mosaic disease, which affects the leaves of tobacco plants, leading to a characteristic mottled appearance.

4. **Size of TMV**: The dimensions of TMV are approximately 300 nm in length and 17.5 nm in diameter. Understanding the size helps in the classification and study of viruses.

5. **Type of Virus**: TMV is classified as a ribovirus, which means it has RNA as its genetic material. Specifically, TMV contains single-stranded RNA.

6. **Comparison with Other Viruses**: It's important to differentiate TMV from other types of viruses. Viruses can be classified based on their genetic material; those with RNA are called riboviruses, while those with DNA are called deoxyriboviruses.

7. **Structure of TMV**: TMV has a protein coat known as a capsid, which is made up of smaller units called capsomeres. The genetic material (RNA) is enclosed within this protein structure.

8. **Conclusion**: Based on the above information, TMV is best described as a single-stranded ribovirus.

**Final Answer**: TMV is a single-stranded ribovirus.

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