( ( Animal cells ) ( ( lack ( ( the ( cellulose ( cells walls ) ) ) ( of ( plant cells ) ) ) ) . ) )
(ROOT (S (NP (NNP Animal) (NNS cells)) (VP (VBP lack) (NP (NP (DT the) (NN cellulose) (NNS cells) (NNS walls)) (PP (IN of) (NP (NN plant) (NNS cells))))) (. .)))
Animal cells lack the cellulose cells walls of plant cells.
(ROOT (S (NP (NNP Plant) (NNS cells)) (VP (VBP have) (NP (NP (NNS structures)) (SBAR (WHNP (WDT that) (NN animal) (NNS cells)) (S (VP (VBP lack)))))) (. .)))