( ( Cell membranes ) ( ( ( ( are ( naturally ( permeable ( to ( some molecules ) ) ) ) ) and ) ( ( have ( cell ( surface ( receptors ( and ( pore proteins ) ) ) ) ) ) ( for ( ( ( ( active or ) passive ) transport ) ( of others ) ) ) ) ) . ) )
(ROOT (S (NP (JJ Cell) (NNS membranes)) (VP (VP (VBP are) (ADJP (RB naturally) (JJ permeable) (PP (TO to) (NP (DT some) (NNS molecules))))) (CC and) (VP (VBP have) (NP (NN cell) (NN surface) (NNS receptors) (CC and) (NN pore) (NNS proteins)) (PP (IN for) (NP (NP (ADJP (JJ active) (CC or) (JJ passive)) (NN transport)) (PP (IN of) (NP (NNS others))))))) (. .)))
Cell membranes are naturally permeable to some molecules and have cell surface receptors and pore proteins for active or passive transport of others.
(ROOT (S (NP (PRP You)) (VP (VBP call) (NP (NP (DT the) (NN movement)) (PP (IN of) (NP (NP (NNS molecules)) (PP (IN across) (NP (DT a) (ADJP (JJ membrane) (PP (IN without) (NP (NP (DT the) (NN input)) (PP (IN of) (NP (NN energy)))))) (JJ passive) (NN transport))))))) (. .)))