Final Exam Study Guide AP III Essay questions to know • What are innate and adaptive immune systems, how they work and how they interact. Adaptive immunity is the ability of the body to defend itself against specific invading agents ▪ Antigens are substances recognized as foreign that provoke immune responses Adaptive immunity has both specificity and memory and is divided into 2 types 1 Cell-mediated 2 An tibodymediated In cellmediated immunity: ▪ An antigen is recognized and bound ▪ A small number of T cells proliferate and differentiate into a clone of effector cells ▪ The antigen is eliminated In antibodymediated immunity: ▪ An antigen is recognized and bound ▪ Helper T cells costimulate the B cell so the B cell can proliferate and differentiate into a clone of effector cells that produce antibodies ▪ The antigen is eliminated Innate immunity refers to a variety of body responses that serve to protect us against invasion of a wide variety of pathogens and their toxins. ▪ We are born with this kind of immunity ▪ Two lines of defense: Nonspecific disease resistance fight a wide variety of invaders. 1 st: Skin and mucous membranes: barriers, antimicrobial substances 2 nd: Internal defenses (cellular defenses), inflammation, and fever • Describe the anatomy and functions of the spleen.