Antigens

• Antigen


  Substance that triggers an immune response
• Pathogen enters the body

  1. Pathogen secretes antigens

  2. White blood cells detect antigens

  3. White blood cells destroy the pathogen
• White blood cells destroy the pathogen
• The immune system tries to ingest the pathogen
• The immune system becomes immune to the pathogen
• Antibodies


  Proteins produced in response to an antigen to neutralize or destroy it
• Antibodies are produced


  1. In vaccines

  2. Passively transferred from mother to child
• Artificial immunity


  Deliberate exposure to antigens to trigger an immune response
• Active immunity


  • Triggers an immune response
  • Provides long-term protection for the individual
• Passive immunity


  • Provides short-term protection
  • Does not trigger an immune response
• Vaccines trigger an immune response
• Antibodies have a short lifespan, the body doesn't maintain them permanently
• Enough people need to have immunity for the whole population to be protected
• Vaccines can have new or limited side effects
• Vaccines protect those who might otherwise get ill
• Vaccines can prevent illnesses from recurring