( ( In males ) ( , ( estrogen ( ( ( ( is ( produced ( from testosterone ) ) ) and ) ( is ( thought ( to ( be ( involved ( in ( ( the formation ) ( of sperm ) ) ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN In) (NP (NNS males))) (, ,) (NP (NN estrogen)) (VP (VP (VBZ is) (VP (VBN produced) (PP (IN from) (NP (NN testosterone))))) (CC and) (VP (VBZ is) (VP (VBN thought) (S (VP (TO to) (VP (VB be) (VP (VBN involved) (PP (IN in) (NP (NP (DT the) (NN formation)) (PP (IN of) (NP (NN sperm)))))))))))) (. .)))
In males, estrogen is produced from testosterone and is thought to be involved in the formation of sperm.
(ROOT (S (NP (DT The) (JJ male) (JJ reproductive) (NN system)) (VP (VBZ consists) (PP (IN of) (NP (NP (NNS structures)) (SBAR (WHNP (WDT that)) (S (VP (VBP produce) (NP (NN sperm) (CC and) (NN secrete) (NN testosterone)))))))) (. .)))