( ( The ions ) ( then ( ( ( diffuse away ) ( from ( the ( membrane III ) ) ) ) . ) ) )
(ROOT (S (NP (DT The) (NNS ions)) (ADVP (RB then)) (VP (VBP diffuse) (PRT (RP away)) (PP (IN from) (NP (DT the) (NNP membrane) (NNP III)))) (. .)))
The ions then diffuse away from the membrane III.
(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)))))) (. .)))