(4)Different cells can respond differently to the same extracellular signal molecule IC)skeletal muscle cell A heart muscle cell (B》 salivary gland cell receptor … secreTION acetylcholine DECREASED RATE AND CONTR FORCE OF CONTRACTION Various responses induced by neurotransmitter acetylcholine(4) Different cells can respond differently to the same extracellular signal molecule Various responses induced by neurotramsmitter acetylcholine