Write salient features of viruses.

Explanation

Salient features of viruses are listed below :
1. Viruses are non-cellular, ultra-microscopic, infectious particles.
2. They are perfect obligate parasities (i.e., parasitic at the gene level) and can not be grown on artificial culture medium. They are inert outside the host cells.
3. They can be precipitated from suspensions and can be crystallised in the form of crystals.
4. Viruses are regarded as intermediate between non-living entities and living organisms.
5. They are highly pathogenic and cause infectious disease in animals and plants.
6. All viruses are nucleoproteins. The nucleic acid is protected by protein coat against attack by nuclease enzyme.