( ( ( Photosynthesis -- ) ( ( ( produces oxygen ) , ) ( ( some ( of which ) ) ( eventually ( forms ( ( ozone high ) ( in ( the atmosphere ) ) ) ) ) ) ) ) ; )
(ROOT (NP (NP (NP (NNS Photosynthesis)) (: --) (NP (NP (JJ produces) (NN oxygen)) (, ,) (SBAR (WHNP (NP (DT some)) (WHPP (IN of) (WHNP (WDT which)))) (S (ADVP (RB eventually)) (VP (VBZ forms) (NP (NP (NN ozone) (NN high)) (PP (IN in) (NP (DT the) (NN atmosphere))))))))) (: ;)))
Photosynthesis -- produces oxygen, some of which eventually forms ozone high in the atmosphere;
(ROOT (S (NP (NP (DT The) (NN process)) (ADJP (JJ responsible) (PP (IN for) (NP (NP (DT the) (NN presence)) (PP (IN of) (NP (NP (NN oxygen)) (PP (IN in) (NP (PRP$ our) (NN atmosphere))))))))) (VP (VBZ is) (NP (NN photosynthesis))) (. .)))