Why a virus is not being considered as true microorganism?

Dear Student!

Viruses are considered to be on the borderline between living and non living organisms. Viruses are non-living when they are alone but when they infect any normal cell they begin their activity and start dividing. In a way, we can say that they are parasites and require host to survive and without the host they become dormant. Hence, it is not considered as true microorganism.

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