( ( Animal ( ( cells and ) protozoans ) ) ( ( lack ( cell walls ) ) . ) )
(ROOT (S (NP (JJ Animal) (NNS cells) (CC and) (NNS protozoans)) (VP (VBP lack) (NP (NN cell) (NNS walls))) (. .)))
Animal cells and protozoans lack cell walls.
(ROOT (S (NP (DT A) (NN cell) (NN wall)) (VP (VBZ is) (RB not) (ADJP (JJ present) (PP (IN in) (NP (NN animal) (NNS cells))))) (. .)))