# The Immune System

Know that the body has an immune system that protects against illness: the skin acts as a barrier, white blood cells identify and destroy germs (bacteria and viruses), and vaccines train the immune system to recognise specific diseases before they cause illness

Builds on: Cells, Tissues & Organs (hard, https://ai.page/c/cells-tissues-and-organs/en.md)

Concept id: the-immune-system. Subject: science. Licence: CC BY-SA 4.0.

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