♻️ap environmental science review

Pathogens and Infectious Diseases

Written by the Fiveable Content Team • Last updated September 2025
Verified for the 2026 exam
Verified for the 2026 examWritten by the Fiveable Content Team • Last updated September 2025

Definition

Pathogens are microorganisms, such as bacteria, viruses, or fungi, that can cause diseases in humans, animals, or plants. Infectious diseases are illnesses caused by these pathogens that can be transmitted from one organism to another.

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