Human Defence Systems - Non-Specific Defences
Biology: AQA GCSE Higher, topic 3.1.9
Non-Specific Defences
The human body has non-specific defences. They are designed to prevent any pathogens from entering the body and causing harm.
Skin
- Skin is a waterproof barrier that pathogens cannot pass through.
- Good bacteria live permanently on our skin, covering the surface and preventing pathogens from growing on our skin.
Stomach acid
- Glands in the stomach wall produce hydrochloric acid, which destroys any pathogens that enter the stomach.
Tears
- Tears contain enzymes that destroy any pathogens that make contact with our eye.
Mucus
- Mucus is produced in the respiratory system and traps the particles and bacteria entering our airways.
Test yourself on Human Defence Systems - Non-Specific Defences
Why does mucus help defend the airways against pathogens?
What two structures in the lining of the nose and throat help produce and clear mucus?