What do viruses require for their growth and reproduction?

Viruses are unique entities that cannot replicate or grow independently. They rely entirely on living cells for their growth and reproduction. Unlike bacteria and other microorganisms, viruses do not have the necessary cellular machinery to carry out metabolic processes on their own. Instead, they must invade a living host cell and hijack the host's cellular machinery to reproduce. The virus attaches to the surface of the living cell, injects its genetic material, and then uses the cell's resources to synthesize new viral particles.

This reliance on living cells distinguishes viruses from other microorganisms that can thrive in dead or artificial environments. Understanding this concept is crucial in microbiology, particularly in fields like mortuary science, where the interaction between microorganisms and living tissue can influence decomposition and preservation methods.