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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.
Bacteria contain RNA and DNA in their cell that contain genetic code. They can live independently and can reproduce. Viruses on the other hand are intracellular organisms that require a living host such as a plant or an animal to multiply. They penetrate the cells of a host and live inside the cells.