key term - Pathogens

Definition

Pathogens are microorganisms, such as viruses and bacteria, that can cause disease in living organisms. They invade the body and disrupt normal bodily functions, leading to illness.

Related terms

Viruses:

Viruses are tiny infectious agents that can only replicate inside living cells. They hijack the host cell's machinery to reproduce and spread.

Bacteria:

Bacteria are single-celled microorganisms that can be found almost everywhere. While some bacteria are harmless or even beneficial, others can cause infections and diseases.

Parasites: Parasites are organisms that live on or inside another organism (the host) and rely on it for survival. They harm the host by taking nutrients or causing damage to tissues.