Human Defence Systems & Vaccination

3 min read · part of the full Exam Guide

Non-specific defences

These stop pathogens getting in at all, and work against any pathogen

Defence	How it works
Skin	a physical barrier; produces antimicrobial secretions; scabs seal wounds
Nose	hairs and mucus trap particles and pathogens
Trachea and bronchi	mucus traps pathogens; cilia (tiny hairs) waft the mucus up to the throat to be swallowed
Stomach	hydrochloric acid kills pathogens in food and drink

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Non-specific defences
The immune system
Vaccination

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