( ( Benthos ( ( The ( plant ( and ( animal organisms ) ) ) ) ( that ( live ( on ( the ( sea floor ) ) ) ) ) ) ) . )
(ROOT (S (VP (VB Benthos) (NP (NP (DT The) (NN plant) (CC and) (NN animal) (NNS organisms)) (SBAR (WHNP (WDT that)) (S (VP (VBP live) (PP (IN on) (NP (DT the) (NN sea) (NN floor)))))))) (. .)))
Benthos The plant and animal organisms that live on the sea floor.
(ROOT (S (NP (NP (VBG Living) (NNS things)) (PP (IN on) (NP (DT the) (NN ocean) (NN floor)))) (VP (VBP are) (VP (VBN known) (PP (IN as) (NP (NNS benthos))))) (. .)))
Living things on the ocean floor are known as benthos.