( ( A protein ) ( ( is ( ( a sequence ) ( of ( ( ( amino acids ) , ) ( which ( ( organic chemists ) ( call residues ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT A) (NN protein)) (VP (VBZ is) (NP (NP (DT a) (NN sequence)) (PP (IN of) (NP (NP (JJ amino) (NNS acids)) (, ,) (SBAR (WHNP (WDT which)) (S (NP (JJ organic) (NNS chemists)) (VP (VBP call) (NP (NNS residues))))))))) (. .)))
A protein is a sequence of amino acids, which organic chemists call residues.
(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)))))))) (. .)))