Humoral response

• What type of lymphocytes are involved in the cell mediated response?

  T lymphocytes
• What is the role of T lymphocytes in the immune response?

  They are involved in the specific immune response
• Where are all lymphocytes made?

  In the bone marrow
• Why are T cells called T cells?

  They mature in the thymus
• What does the term "cell mediated response" refer to?

  The response of T cells to antigens
• What are antigen presenting cells (APCs)?

  Cells that present non-self antigens
• What types of cells can act as antigen presenting cells?

  Infected body cells, macrophages, and cancer cells
• How do antigen presenting cells trigger B cell responses?

  By presenting antigens to T cells
• Why is the response called "cell mediated"?

  Because T cells respond to presented antigens
• What happens after a pathogen is engulfed by phagocytosis?

  Antigens are placed on the surface of APCs
• What do helper T cells do when they bind to antigens?

  They activate and start dividing by mitosis
• What is the result of helper T cells dividing by mitosis?

  Large numbers of helper T cells are produced
• What can helper T cells differentiate into?

  Memory cells, cytotoxic T cells, and stimulate B cells
• What do cytotoxic T cells do?

  They destroy abnormal or infected cells
• What protein do cytotoxic T cells release to kill infected cells?

  Perforin
• What is the function of perforin?

  It creates pores in infected cell membranes
• What happens to a cell when perforin creates pores in its membrane?

  The cell can no longer maintain homeostasis
• Why do cytotoxic T cells destroy infected cells during a cold?

  To prevent the virus from replicating
• What is the summary of the cell-mediated response?

  • Involves T lymphocytes responding to antigens
  • Antigen presenting cells include:
  • Phagocytes
  • Abnormal self cells
  • Non-self cells
  • Helper T cells divide and stimulate:
  • B cells
  • Phagocytes
  • Memory cells
  • Cytotoxic T cells
  • Cytotoxic T cells kill infected cells using perforin
• What is the outcome of cytotoxic T cells releasing perforin?

  Cell death occurs
• What happens to cells when they are destroyed by cytotoxic T cells?

  They shrivel or lyse