( ( ( ( ( The ( porcine heart ) ) , ) ( like ( a ( human heart ) ) ) ) , ) ( ( has ( ( ( four chambers ) and ) ( four valves ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (JJ porcine) (NN heart)) (, ,) (PP (IN like) (NP (DT a) (JJ human) (NN heart))) (, ,)) (VP (VBZ has) (NP (NP (CD four) (NNS chambers)) (CC and) (NP (CD four) (NNS valves)))) (. .)))
The porcine heart, like a human heart, has four chambers and four valves .
(ROOT (S (NP (EX There)) (VP (VBP are) (NP (NP (CD four) (NNS valves)) (PP (IN in) (NP (DT the) (NN heart))))) (. .)))