How are viruses and cells similar?

Viruses and cells are similar in a number of ways. Both are too tiny to be visible with the naked eye. The only way scientists can study their general structure and morphology is by using a microscope. Both viruses and cells contain genetic material in the form of DNA and/or RNA and both can evolve and replicate to produce more organisms similar to themselves. Both are disease-causing organisms, capable of causing diseases in other life forms.