title: The immune system: its development and functions.
mesh_terms: D000818:Animals; D000917:Antibody Formation; D001402:B-Lymphocytes / Q000502:physiology; D002645:Chickens / Q000276:immunology; D006801:Humans; D007109:Immunity; D007111:Immunity, Cellular; D007112:Immunity, Maternally-Acquired; D007070:Immunoglobulin A; D007072:Immunoglobulin D; D007073:Immunoglobulin E; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007153:Immunologic Deficiency Syndromes / Q000209:etiology; D008213:Lymphocyte Activation; D013601:T-Lymphocytes / Q000502:physiology
chemical_list: D007070:Immunoglobulin A; D007072:Immunoglobulin D; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007073:Immunoglobulin E