complement

(kom’ple-ment). A_ thermolabile, ferment-like body existing in many serums and normally in cell-protoplasm. The complement is the active element in lysis, but can act only in conjunction with the amboceptor, which serves as am intermediary for fastening the complement to the cell on which it acts. The complement is made up of two groups, a haptophore group, by which it is attached to the complement, and a foxophore, which is the active portion of the complement. The complement is called also alexin, cytase, and end-body. See Ehrlich's side-chain theory, under theery. c. deflection, c. deviation, c. fixation. See fixation of the complement. domimant c., that one of several complements which exerts the specific action.