Why Viruses Aren't Living — NEET Biology

Correct answer: C — S2, S3 and S4 only

The core concept tested is why viruses are not part of Whittaker's five-kingdom classification. S1: Incorrect. NCERT states, 'In the five kingdom classification of Whittaker there is no mention of lichens and some acellular organisms like viruses, viroids and prions.' Viruses were not included in any kingdom. S2: Correct. NCERT states, 'The viruses are non-cellular organisms that are characterised by having an inert crystalline structure outside the living cell.' S3: Correct. NCERT states, 'Once they infect a cell, they take over the machinery of the host cell to replicate themselves, killing the host. ... Viruses are obligate parasites.' S4: Correct. NCERT states, 'Viruses did not find a place in classification since they are not considered truly ‘living’, if we understand living as those organisms that have a cell structure.' The lack of cell structure and dependency on host machinery implies absence of independent metabolism. S5: Incorrect. Viruses are obligate intracellular parasites and cannot reproduce autonomously outside host cells, nor do they exhibit independent metabolism. They are inert outside a host. Therefore, statements S2, S3, and S4 are correct.