"There are some characteristics of viruses that put them on the borderline [of being alive] - they have genetic material: DNA or RNA. It's not the same thing as a rock, but it's clearly not the same thing as even bacteria, in terms of that self-sustaining and self-generated action."Are viruses the basic unit of life?
So the idea of an organism as the basic unit of life is likely to have had its day. Viruses are alive, if only because life is a widespread system of evolving chemistry. Not everyone agrees with this distinction, based on the fact that, like rocks, viruses do not have self-generated or self-sustaining actions.Why are viruses considered non-living things?
Many people say they are non-living because they cannot reproduce without the aid of a host. Viruses also do not metabolize food into energy or have organized cells, which are usually characteristics of living things. They do not have an organized cell structure.How big is a virus?
When you consider that viruses range in size from around 20 to 800 nanometres, there must be a lot of them! And yet, for something so widespread on our planet, there's actually quite a lot we don't often hear about viruses.