Guide

    Cards (14)

    • Immune system
      Protects the body from infection
    • Natural barriers that reduce the risk of infection
      • Skin
      • Blood clotting to seal wounds
      • Inflammation to localise breaks in the barrier
      • Phagocytosis to destroy invading microbes
      • Ciliated mucous membranes that trap microbes in inhaled air
    • Phagocytosis
      Process of destroying invading microbes
    • Receptors
      Detect antigens as foreign to the body
    • Phagocytosis
      1. Microbe taken up
      2. Phagosome formed
      3. Lysosome fuses with phagosome
      4. Phagolysosomes digest microbe
    • Lysozyme
      Kills bacteria in tears, saliva and stomach acid
    • Exocytosis
      Process of releasing substances from a cell
    • Cell-mediated immune response
      Involves detection of specific antigens, production of T lymphocytes, and activation of phagocytes and cytotoxic T cells
    • Humoral response
      Involves B lymphocytes detecting specific antigens, producing plasma cells and memory cells, and antibodies that bind to and inactivate antigens
    • Antibodies
      Proteins that bind to and inactivate antigens
    • Antigen-antibody complex

      Increases the rate of engulfment by phagocytes
    • Invading pathogens
      • Bacteria
      • Viruses
    • Memory cells remain in the circulation ready to divide if the same antigen is encountered again
    • Antibodies circulate in blood and tissue fluid in readiness to respond to a future infection by the same pathogen