cell mediated 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 do T cells mature?

  In the thymus
• What is the second line of defense after a pathogen enters the bloodstream?

  The specific immune response
• What are antigen presenting cells (APCs)?

  Cells that present non-self antigens on their surface
• What does APC stand for?

  Antigen presenting cell
• What types of cells can act as antigen presenting cells?

  Infected body cells, macrophages, and cancer cells
• Why is the response called "cell mediated"?

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

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

  They become activated and divide by mitosis
• What is the result of the activation of helper T cells?

  They replicate to make large numbers of cells
• What can activated 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 embeds in its membrane?

  It causes the cell to die
• How do cytotoxic T cells help during a viral infection?

  They destroy infected cells to prevent replication
• What is the summary of the cell-mediated response?

  • Involves T lymphocytes responding to antigens
  • Antigen presenting cells include phagocytes and abnormal cells
  • Helper T cells divide and stimulate B cells or become memory cells
  • Cytotoxic T cells kill infected cells using perforin
• What causes a sore throat during a cold?

  Cytotoxic T cells destroying infected cells
• What is the role of memory cells in the immune response?

  They store memory of specific antigens
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