BIOL 103 Chapter Notes -Immunoglobulin M, Immunoglobulin D, Immunoglobulin G
Document Summary
Mammals have five classes: igm, ige, iga, igi, igd. Some vertebrates have only some of the other five classes and also express unique immunoglobin not found in mammals. They have proteins containing ig-domains (ig-folds) w/ sequences that are similar to those of immunoglobins. Ancestral to immunoglobulins; may carry out immune activity. Most abundant immunoglobin in mammals: igm and igg. Provides most of the specific immunity against bacteria and viruses. Ige: defense against multicellular parasites and mediates allergic responses. Mast cell ige binds to antigen-->mast cell secretes histamine into extracellular fluid-- >causes vasodilation + contributes to the allergic response. Iga: secreted by plasma cells in linings of gi, respiratory, and genitourinary tracts, tear ducts, and salivary glands. Acts locally in these linings, or on the surface. Secretes by mammary glands of mammals shortly after birth; major antibody in milk. Igd: f"n unclear; on surface of b-cells and in blood.