( ( ( ( ( ( ( The rate ) ( of ( most ( chemical reactions ) ) ) ) ( can ( be ( ( speeded up ) ( by ( substances ( called catalysts ) ) ) ) ) ) ) , ) and ) ( ( ( the catalysts ) ( that ( are ( produced ( by ( living organisms ) ) ) ) ) ) ( are ( called enzymes ) ) ) ) . )
(ROOT (S (S (NP (NP (DT The) (NN rate)) (PP (IN of) (NP (JJS most) (NN chemical) (NNS reactions)))) (VP (MD can) (VP (VB be) (VP (VBN speeded) (PRT (RP up)) (PP (IN by) (NP (NP (NNS substances)) (VP (VBN called) (NP (NNS catalysts))))))))) (, ,) (CC and) (S (NP (NP (DT the) (NNS catalysts)) (SBAR (WHNP (WDT that)) (S (VP (VBP are) (VP (VBN produced) (PP (IN by) (NP (VBG living) (NNS organisms)))))))) (VP (VBP are) (VP (VBN called) (NP (NNS enzymes))))) (. .)))
The rate of most chemical reactions can be speeded up by substances called catalysts , and the catalysts that are produced by living organisms are called enzymes .
(ROOT (S (NP (PRP You)) (VP (VBP call) (NP (NP (NNS catalysts)) (SBAR (WHNP (WDT that)) (S (VP (VBP are) (VP (VBN found) (ADVP (RB inside)) (PP (IN of) (S (VP (VBG living) (NP (NNS things) (NNS enzymes))))))))))) (. .)))