( ( A protein ) ( ( is ( ( an ( organic compound ) ) ( ( made up ) ( of ( ( small molecules ) ( called ( amino acids ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT A) (NN protein)) (VP (VBZ is) (NP (NP (DT an) (JJ organic) (NN compound)) (VP (VBN made) (PRT (RP up)) (PP (IN of) (NP (NP (JJ small) (NNS molecules)) (VP (VBN called) (NP (JJ amino) (NNS acids)))))))) (. .)))
A protein is an organic compound made up of small molecules called amino acids .
(ROOT (S (NP (DT A) (NN protein)) (VP (VBZ is) (NP (NP (DT an) (JJ organic) (NN compound)) (VP (VBN made) (PRT (RP up)) (PP (IN of) (NP (NP (JJ small) (NNS molecules)) (VP (VBN called) (NP (JJ amino) (NNS acids)))))))) (. .)))