( ( Signal Transduction ) ( ( Receptors ( ( ( The ( primary mechanism ) ) ( ( by which ) ( ( a ( cell senses ) ) ( ( ( extracellular stimuli ) and ) ( consequently ( evokes ( ( an intracellular ) ( signaling cascade ) ) ) ) ) ) ) ) ( is ( through ( membrane receptors ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Signal) (NNP Transduction)) (VP (VBZ Receptors) (SBAR (S (NP (NP (DT The) (JJ primary) (NN mechanism)) (SBAR (WHPP (IN by) (WHNP (WDT which))) (S (NP (DT a) (NN cell) (NNS senses)) (VP (VP (VBP extracellular) (NP (NNS stimuli))) (CC and) (VP (ADVP (RB consequently)) (VBZ evokes) (NP (NP (DT an) (NN intracellular)) (VP (VBG signaling) (NP (NN cascade))))))))) (VP (VBZ is) (PP (IN through) (NP (JJ membrane) (NNS receptors))))))) (. .)))
Signal Transduction Receptors The primary mechanism by which a cell senses extracellular stimuli and consequently evokes an intracellular signaling cascade is through membrane receptors.
(ROOT (S (NP (JJ Enzymatic) (NNS cascades)) (VP (VBP help) (VP (VB amplify) (NP (NP (DT the) (NNS effects)) (PP (IN of) (NP (NN extracellular) (NNS signals)))))) (. .)))