2018 · Q36
Which one of the following statements explains higher mutation rate and faster evolution found in RNA virus ?
General KnowledgeBiology
- ARNA is relatively unstable compared to DNA.
- BVirus can multiply only within the living cell of a host.
- CMetabolic processes are absent in virus.
- DVirus can remain latent for a long period.
Explanation
RNA is chemically less stable than DNA (the 2'-hydroxyl group makes it prone to hydrolysis), and RNA-dependent RNA polymerases lack the proofreading function of DNA polymerases. As a result, replication errors accumulate rapidly in RNA viruses, producing higher mutation rates and faster evolution. The other statements about viruses are true in general but do not explain the elevated mutation rate. Hence RNA's relative instability is the explanation.