BIOL 2051 Study Guide - Passive Immunity, Exotoxin, Formaldehyde
Document Summary
Immunity: ability of an organism to resist infection. All cells involved in immunity originate from common stem cells in bone marrow. Immune system: protects against foreign cells and macromolecules: antigen/immunogen: foreign cells or macromolecules that induce immune system. Types of immunity: naturally acquired immunity, artificially acquired immunity. Naturally acquired immunity: can be classified as active or passive. Naturally acquired active immunity: host produces antibodies and t cells in response to an infection. Naturally acquired passive immunity: occurs when antibodies are passed from one host to another, ex. Antibodies pass through placenta from mother to fetus (or through breast milk) These circulate in infants system for several months after birth. Artificially acquired immunity: can be classified as active or passive immunity. Artificially acquired active immunity: result of vaccination, host makes antibodies that can last for years. To reduce risks, vaccines contain inactivated pathogens or their products: toxoid: chemically modified exotoxin retains antigenicity but loses toxicity.
