because none of them is capable of replicating itself outside the host
viruses are considered parasites (obligate parasites) because they cannot exist on their own. they need the host cell's machinery to reproduce so they cannot "survive" (technically not living) outside the cell.
parasitic mode of nutrition
Parasites can carry and transmit viruses, but they do not "cause" them.
They are obligate paracites.They cannot multiply without another living cell
Viruses
Tapeworms, fleas, leeches, and most viruses, and some bacteria all fall under the label of parasites. Parasites benefit from another organism at that organism's expense.
No; viruses are sub-Cellular 'virons', while parasites are frequently multi-cellular organisms.
Yes because all the viruses uses host cell mechanisms to reproduce and then at the end of the reproduction process it destroy the host cell.Therefore there is no non-parasitic viruses.All viruses are parasitic.
Because they are obligate parasites
bacteria, viruses, fungi and parasites
These are called intracellular parasites. All viruses are in this group. Obligate bacteria types include Rickettisae and Chlamydia. Also there are a few that are considered to be non-obligate:Mycobacterium and Brucella.
They both destroy the cells that they attack.