Non-Specific Defence Systems

• What are the two main defense systems of the human body against pathogens?

  Nonspecific defense system and immune system
• What is the primary function of the nonspecific defense system?

  • Prevent pathogens from entering the human body
• Name a few diseases caused by pathogens.

  Salmonella food poisoning, HIV, malaria, measles
• What are the four main parts of the nonspecific defense system?

  • Skin
  • Nose
  • Trachea and bronchi
  • Stomach
• How does the skin protect the body from pathogens?

  The skin forms a protective layer and produces sebum that kills bacteria.
• What is sebum?

  Sebum is an oily substance produced by the skin that can kill bacteria.
• What happens when the skin is damaged?

  • The skin scabs over to prevent pathogens from entering the body.
• What are some openings in the body that are not covered by skin?

  Nostrils and mouth
• How does the nose help prevent pathogens from entering the body?

  The nose contains hair and mucus that trap pathogens.
• What role do cilia play in the respiratory system?

  Cilia move mucus upwards towards the throat to trap and expel pathogens.
• How does the stomach defend against pathogens?

  The stomach contains hydrochloric acid that kills pathogens.
• Why can pathogens still enter the human body despite nonspecific defense systems?

  Pathogens can bypass nonspecific defenses and cause disease.
• What is the relationship between the nonspecific defense system and the immune system?

  • The nonspecific defense system prevents pathogens from entering.
  • The immune system provides additional protection against pathogens that enter.