( respiratory ( ( ( center ( The ( ( structure or ) portion ) ) ) ( of ( the brain ) ) ) ( ( stem ( that ( regulates ( ( the ( ( depth and ) rate ) ) ( of breathing ) ) ) ) ) . ) ) )
(ROOT (S (ADVP (RB respiratory)) (NP (NP (RB center) (DT The) (NN structure) (CC or) (NN portion)) (PP (IN of) (NP (DT the) (NN brain)))) (VP (VBP stem) (SBAR (IN that) (S (VP (VBZ regulates) (NP (NP (DT the) (NN depth) (CC and) (NN rate)) (PP (IN of) (NP (NN breathing)))))))) (. .)))
respiratory center The structure or portion of the brain stem that regulates the depth and rate of breathing.
(ROOT (S (NP (DT The) (NN brain) (NN stem)) (VP (VBZ regulates) (NP (NP (DT the) (NN rate)) (PP (IN of) (NP (NN breathing))))) (. .)))