( ( Particles ( that ( ( ( are ( required ( for ( cellular function ) ) ) ) but ) ( are ( unable ( to ( ( diffuse freely ) ( across ( a membrane ) ) ) ) ) ) ) ) ) ( ( ( ( enter ( through ( a ( membrane ( transport protein ) ) ) ) ) or ) ( are ( taken ( in ( by ( means ( of ( ( endocytosis , ) ( where ( ( the membrane ) ( allows ( for ( a ( vacuole ( to ( ( ( join ( onto it ) ) and ) ( ( push ( its contents ) ) ( into ( the cell ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (NNS Particles)) (SBAR (WHNP (WDT that)) (S (VP (VP (VBP are) (VP (VBN required) (PP (IN for) (NP (JJ cellular) (NN function))))) (CC but) (VP (VBP are) (ADJP (JJ unable) (S (VP (TO to) (VP (VB diffuse) (ADVP (RB freely)) (PP (IN across) (NP (DT a) (NN membrane)))))))))))) (VP (VP (VBP enter) (PP (IN through) (NP (DT a) (JJ membrane) (NN transport) (NN protein)))) (CC or) (VP (VBP are) (VP (VBN taken) (PP (IN in) (IN by) (NP (NP (NNS means)) (PP (IN of) (NP (NP (NNS endocytosis)) (, ,) (SBAR (WHADVP (WRB where)) (S (NP (DT the) (NN membrane)) (VP (VBZ allows) (PP (IN for) (NP (DT a) (NN vacuole) (S (VP (TO to) (VP (VP (VB join) (PP (IN onto) (NP (PRP it)))) (CC and) (VP (VB push) (NP (PRP$ its) (NNS contents)) (PP (IN into) (NP (DT the) (NN cell))))))))))))))))))) (. .)))
Particles that are required for cellular function but are unable to diffuse freely across a membrane enter through a membrane transport protein or are taken in by means of endocytosis, where the membrane allows for a vacuole to join onto it and push its contents into the cell.
(ROOT (S (NP (NP (DT The) (NN name)) (PP (IN for) (NP (NP (JJ membrane-bound) (NNS sacs)) (SBAR (WHNP (WDT that)) (S (VP (VBP function) (PP (IN in) (NP (NN storage) (CC and) (NN transport))))))))) (VP (VBZ is) (ADJP (JJ vacuoles))) (. .)))