Bacteria and viruses
ScienceDefinition
Bacteria are single-celled prokaryotic organisms that can reproduce independently, while viruses are non-living particles made of genetic material (DNA or RNA) enclosed in a protein coat that can only replicate inside a host cell. Both can cause disease, but they differ fundamentally in structure, reproduction, and treatment.
Examples
- Strep throat is caused by Streptococcus bacteria and can be treated with antibiotics
- Influenza is caused by a virus and cannot be treated with antibiotics—only antivirals or vaccines help
- E. coli bacteria in your gut are mostly beneficial, aiding digestion and producing vitamin K
Key Fact
Antibiotics treat bacterial infections; they do NOT work against viruses.
Study This Concept
Practice bacteria and viruses with free review games in these units: