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• Which of the following is most associated with bacterial food poisoning?

  High protein, moist foods
• Which of the following leukocytes are found resident in tissues?

  Macrophages, neutrophils, mast cells
• Which of the following statements about the immune system is correct?

  The innate immune system is immediate, non-specific and humoral-mediated
• Which of the following statements about the processes of repair and regeneration is correct?

  Regeneration requires re-initiation of developmental programmes
• Which of the following T cells is grouped with the innate immune system?

  Natural killer cell
• Which of the following statements about eosinophils is NOT correct?

  They attack and destroy cancer cells
• Name one of the chemo-attractants that will attract monocytes to the source of the chemo-attractant (1 mark)

  Chemokines
• Identify four (4) locations where immune cells are found in the human body (4 marks)?

  Bone marrow, lymph nodes, spleen, mucosal surfaces (such as in the gut)
• What pathogens are the main target of neutrophils (2 marks)?

  Bacteria and fungi
• Identify and briefly describe the three (3) lines of defense of the immune response (6 marks).

  1. Physical barriers: Skin, mucous membranes, and other barriers that prevent pathogens from entering the body.
  2. Innate immune response: Immediate, non-specific response involving phagocytes, natural killer cells, and inflammation.
  3. Adaptive immune response: Specific response involving B cells and T cells that recognize and attack specific pathogens
• Identify three mechanisms by which the immune system screens out “self” recognizing antibody-producing cells

  1. Negative selection in the bone marrow and thymus.
  2. Regulatory T cells (Tregs) suppressing auto-reactive cells.
  3. Peripheral tolerance mechanisms, such as anergy and deletion of autoreactive cells.
• Briefly describe the two main roles of Natural Killer T cells (2 marks)

  1. Recognizing and eliminating cells infected with certain viruses or other pathogens.
  2. Modulating immune responses by producing cytokines.