( ( ( ( Membrane Excitability ) and ) ( Ion Channels ) ) ; )
(ROOT (NP (NP (NP (NNP Membrane) (NNP Excitability)) (CC and) (NP (NNP Ion) (NNP Channels))) (: ;)))
Membrane Excitability and Ion Channels;
(ROOT (NP (NP (NP (NNP Ion) (NNP channels) (NNP facilitate)) (PRN (-LRB- -LRB-) (PRP s) (-RRB- -RRB-))) (NP (NP (DT the) (NN diffusion)) (PP (IN of) (NP (NP (NNS ions)) (PP (IN across) (NP (DT a) (NN membrane)))))) (. .)))