( ( These organisms ) ( usually ( ( have ( ( thick ( cell walls ) ) ( that ( ( ( ( prevent dehydration ) and ) generally ) ( divide slowly ) ) ) ) ) . ) ) )
(ROOT (S (NP (DT These) (NNS organisms)) (ADVP (RB usually)) (VP (VBP have) (NP (NP (JJ thick) (NN cell) (NNS walls)) (SBAR (WHNP (WDT that)) (S (VP (VP (VBP prevent) (NP (NN dehydration))) (CC and) (ADVP (RB generally)) (VP (VBP divide) (ADVP (RB slowly)))))))) (. .)))
These organisms usually have thick cell walls that prevent dehydration and generally divide slowly.
(ROOT (S (NP (DT The) (NN cell) (NN wall) (NNS acts)) (VP (VP (PP (IN as) (NP (NP (DT an) (JJ extra) (NN layer)) (PP (IN of) (NP (NN protection))))) (, ,) (VBZ helps) (NP (DT the) (NN cell)) (VP (VB maintain) (NP (PRP$ its) (NN shape)))) (, ,) (CC and) (VP (VBZ prevents) (NP (NN dehydration)))) (. .)))