Question

Which of the following statements is true?

• A. TMV has a double stranded RNA molecule
• B. Most plant viruses are RNA viruses.
• C. Bacteriophage has a double stranded RNA molecule.
• D. Most animal viruses are RNA viruses.

Answer 1

The correct option is B Most plant viruses are RNA viruses.

TMV (Tobacco Mosaic Virus) is a rod-shaped virus. The rod has a core which contains helically coiled single stranded RNA. There is a protective covering of protein called capsid around the infective part. Capsid consists of small subunits called capsomeres and has antigenic property. In general, viruses that infect plants have single stranded RNA and viruses that infect animals have either single or double stranded RNA or double stranded DNA.
Bacterial viruses or bacteriophages (viruses that infect the bacteria) are usually double stranded DNA viruses.