As the human body enters its senior years, its ability to fight off infection and other health problems diminishes significantly.

Immune System (March 2001) Introduction Fluid Systems of the Body The Blood System The Lymph System Innate Immunity Surface Barriers or Mucosal Immunity Normal Flora Phagocytes Adaptive or Acquired Immunity Cell-mediated Immunity Humoral Immunity Summary Objectives Terms the student should know are in blue. Introduction The human immune system is a truly amazing constellation of responses to ...