BIOL 3120 Lecture Notes - Lecture 1: Gnathostomata, B Cell, Clonal Selection
Document Summary
Le(cid:272)ture (cid:1005) ch (cid:1005) o(cid:448)er(cid:448)ie(cid:449) of the i(cid:373)(cid:373)u(cid:374)e syste(cid:373) Immunity = a state of protection against foreign pathogens or substances (antigens) Responses are tailored to the type of organism involved. Immune system has tolerance which prevents host damage --- self/non-self discrimination. Two branches: innate and adaptive adaptive immune responses generate memory. Innate: first line of defense use germline-encoded recognition molecules. Recognize evolutionarily preserved pathogens limited subsets; fixed; all humans recognize same pathogens. No two people are same; generate new receptors all the time. Becomes better and better after days = adaptive. Activation of innate response produces signals that stimulate adaptive response. Innate reacts fast and reaches the maximum fast, but always gives the same response. Adaptive is slower, and its primary response is weaker, but upon secondary exposure, it ramps up fast, and the magnitude increases, and recognition molecules have higher affinity and better responses. Highly specific only would be fast for antigen a in this case.
