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A virus has either a DNA or an RNA genome and is called a DNA virus or an RNA virus, respectively. The vast majority of viruses have RNA genomes. Plant viruses tend to have single-stranded RNA genomes and bacteriophages tend to have double-stranded DNA genomes.
They both contain genetic material (RNA OR DNA), and they both reproduce. A virus is a small infectious agent that can replicate only inside the living cells of other organis â¦ ms. Viruses infect all types of organisms, from animals and plants to bacteria and archaea.iruses do not behave like other living cells. For one, they can only reproduce within other organisms. And essentially that is about all they do. Granted there are negative r â¦ eprocussions for the host organism, but the virus itself simply multiplies.