Question

Which of the following is the largest virus?
A) Penicillium virus
B) Wound tumour virus
C) Pox virus
D) None of the above

Answer 1

Viruses are not considered true cells. They are called particles as they are inanimate unless inside a host cell. These particles may contain molecules of DNA or RNA which could be single or double stranded.

Complete answer:
The correct answer to this question is C. The pox virus is an oval, double stranded DNA virus, with a size of 240 x 300 nm. These viruses can infect humans very efficiently. Naturally released viruses also contain an outer membrane which is added as they leave the host cells.

Option A is incorrect. Penicillium is not a virus, but a mould, or in layman terms, a fungus. It is very famous for the accidental discovery of penicillin’s antibacterial properties by Alexander Fleming.

The wound tumour virus is a virus that infects plants and invertebrates. It is an RNA virus and is much smaller in size than the Pox virus. Option B is incorrect.

Option D is not the right answer as option C is correct.
The most well-known Pox virus is the one that is responsible for smallpox Variola, and the related virus, cowpox. It causes a very serious disease characterised by skin lesions that was often fatal. Due to intensive vaccination against the disease, smallpox was officially declared to be eradicated in 1980.

Hence the correct answer is OPTION(C)

Note: Vaccination against smallpox was a major step in immunisation. This was done by Edward Jenner who took samples from cowpox sores and injected them into healthy individuals and then infected them with small pox after a few days.