BIO 311C Lecture Notes - Lecture 12: B Cell, Macrophage, Antigen
Document Summary
Immune system: pathogens are anything that"s foreign: bacterium, fungus, virus, we have cells and proteins that combat them. Innate immunity present when we are born. Prevent entry via barrier defenses (skin, mucous membranes, body fluids) skin has low ph, mucous membrane trap, saliva tears and mucus have lysozymes. Destroy via phagocytosis surface proteins detect unique features of bacteria fungus and viruses: macrophage found in tissues/organs can engulf foreign substances and destroy them. Acquired immunity is what we acquire later on in life not specific. Antigens are the pathogens that elicit a response from a t or b cell. Antigen receptors allow t or b cells to bind to antigens. B cell antigen receptors recognize an antigen on a pathogen and they release antibodies that mark the pathogen for destruction. When you are first exposed to a pathogen your body takes a few weeks to respond if you are exposed a second time, your body reacts way faster (half the time)
