The immune system

• Immune system


  Protects us against pathogens
• Immune system


  • Destroys pathogens and any toxins they produce
  • Protects us in case the same type of pathogen invades us again in the future
• White blood cells


  Involved in the immune system
• How white blood cells destroy pathogens

  1. Detect chemicals released from pathogen

  2. Ingest pathogen

  3. Use enzymes to destroy pathogen
• Phagocytosis


  The process of white blood cells ingesting and destroying pathogens
• How white blood cells destroy pathogens using antibodies

  1. White blood cells produce antibodies

  2. Antibodies stick to pathogens

  3. This triggers the pathogens to be destroyed
• Antibodies


  • Extremely specific to one type of pathogen
  • Can remain in the blood for a long time to protect against future infection
• How white blood cells protect against toxins

  1. White blood cells produce antitoxins

  2. Antitoxins stick to toxin molecules

  3. Prevents toxins from damaging cells