Non-specific defences

• Non-specific human defences:

  • Skin
  • Nose
  • Stomach
  • Trachea and bronchi
• Skin (as a defence system) :

  • acts as a physical barrier
  • produces antimicrobial secretions to kill pathogens
  • skin flora (good microorganisms) compete with bad microorganisms for space and nutrients
• Nose (as a defence system):

  • hairs and mucus trap particles and pathogens
• Trachea and Bronchi (as a defence system):

  • mucus traps pathogens
  • cilia move mucus to be swallowed
• Stomach (as a defence system):

  • hydrochloric acid kills pathogens