( ( In ( order ( for ( a ( chemical ( to ( affect ( the brain ) ) ) ) ) ) ) ) ( it ( ( must ( bind ( to ( ( a ( receptor site ) ) ( capable ( of ( receiving it ) ) ) ) ) ) ) . ) ) )
(ROOT (S (PP (IN In) (NP (NP (NN order)) (PP (IN for) (NP (DT a) (NN chemical) (S (VP (TO to) (VP (VB affect) (NP (DT the) (NN brain))))))))) (NP (PRP it)) (VP (MD must) (VP (VB bind) (PP (TO to) (NP (NP (DT a) (NN receptor) (NN site)) (ADJP (JJ capable) (PP (IN of) (S (VP (VBG receiving) (NP (PRP it)))))))))) (. .)))
In order for a chemical to affect the brain it must bind to a receptor site capable of receiving it.
(ROOT (S (NP (NNP Addiction)) (VP (VBZ affects) (NP (NP (DT the) (JJ dopamine) (NNS receptors)) (PP (IN within) (NP (DT the) (NN brain))))) (. .)))