<prompt> When two different chemical set on two different receptors and their response is opposite to each other on the same cell,this is called asPhysiological antagonismChemical antagonismReversible antagonismCompetitive antagonism  <response>: Ref-KDT 6e p56 Physiological agonism describes the action of a substance which ultimately produces the same effects in the body as another substance--as if they were both agonists at the same receptor--without actually binding to the same receptor 