Lesson · S.2.5
Microorganisms and disease
Bacteria, viruses, fungi, and protozoa: what sets each pathogen apart and how that difference shapes treatment.
ObjectiveS.2.5Read2 minExam weightBiology ≈ 20% of Science
This lesson is part of the full Study Guide
Unlock every lesson, unit, and quiz across all four subjects. The Science biology unit is included.
See editions and pricing →What you will be able to do
- Sort a pathogen into bacteria, virus, fungus, or protozoan.
- Explain why antibiotics work on bacteria but not viruses.
- Match each pathogen type to its typical treatment.
What the lesson concludes
- Bacteria are complete cells and can be targeted directly by antibiotics.
- Viruses are not cells; they hijack a host cell to reproduce, so antibiotics do not work on them.
- Fungal infections are treated with antifungal medication, not antibiotics.
- Protozoa are more complex single-celled organisms; malaria is a common example.
- Sort the pathogen type first, then reason about treatment and spread.