( Proteins ( ( are ( made ( by ( ( chaining together ) ( ( small molecules ) ( called ( amino acids ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNPS Proteins)) (VP (VBP are) (VP (VBN made) (PP (IN by) (S (VP (VBG chaining) (PRT (RP together)) (NP (NP (JJ small) (NNS molecules)) (VP (VBN called) (NP (JJ amino) (NNS acids))))))))) (. .)))
Proteins are made by chaining together 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)))))))) (. .)))