NEETBotanyBiological Classification
How are viruses smaller than bacteria?
Options
- AThey can pass through bacteria-proof filters
- BThey are not as small as bacteria
- CThey are larger than bacteria
- DNone of the above
Correct answer
A. They can pass through bacteria-proof filters
Step-by-step solution
Virus means venom or poisonous fluid. Dmitri Ivanowsky (1892) recognised certain microbes as causal organism of the mosaic disease of tobacco. These were found to be smaller than bacteria because they passed through bacteria-proof filters. M.W. Beijerinek(1898) demonstrated that the extract of the infected plants of tobacco could cause infection in healthy plants and named the new pathogen “virus” and called the fluid as Contagium vivum fluidum (infectious living fluid). W.M. Stanley (1935) showed that viruses coul