Pentamerle lgN malecules bind to antigene igG molscul山bind t地anilgens on becterlal surface and adopt etaple'lom on bect恤rlal aurfac Fig. 9.36 C1g binds to a single IgM molecule Clg binde to a least two IgG molecules BIndlng of Clg to Immunoglobulln aclvatea Cir,whkch cleava ad氯Ga88e88Pute87g