( ( The ( hormone progesterone ) ) ( ( is ( produced ( by ( ( a structure ) ( called ( ( ( the ( corpus luteum ) ) , ) ( located ( on ( the ovary ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NN hormone) (NN progesterone)) (VP (VBZ is) (VP (VBN produced) (PP (IN by) (NP (NP (DT a) (NN structure)) (VP (VBN called) (NP (NP (DT the) (NN corpus) (NN luteum)) (, ,) (VP (VBN located) (PP (IN on) (NP (DT the) (NN ovary)))))))))) (. .)))
The hormone progesterone is produced by a structure called the corpus luteum, located on the ovary.
(ROOT (S (NP (NP (DT The) (NNS cells)) (PP (IN in) (NP (DT the) (NN follicle)))) (VP (VP (VBP undergo) (NP (JJ physical) (NNS changes))) (CC and) (VP (VBP produce) (SBAR (S (NP (DT a) (NN structure)) (VP (VBD called) (NP (DT a) (NN corpus) (NN luteum))))))) (. .)))