There are a number of similarities between viruses and cells. Both are too small to be seen with naked eyes and require a microscope for observation. Both contain genetic material, in the form of DNA and/or RNA. Both of them can replicate, that is, produce more organisms similar to themselves. Both of them are capable of causing diseases to other life forms.
The differences between the two far outweigh the similarities. For example, bacteria contain both DNA and RNA, while the viruses contain either DNA or RNA. Bacteria can replicate on their own and are capable of performing all the functions of living organisms. In comparison, viruses are not even considered living organisms. They require a host cell to carry out life processes, such as replication and carrying out genetic instructions, etc. Bacteria are relatively bigger in size than viruses.
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