( ( ( ( ( ( The anode ) ( is ( ( the electrode ) ( ( at which ) ( oxidation occurs ) ) ) ) ) , ) and ) ( ( the cathode ) ( is ( ( the electrode ) ( ( at which ) ( reduction occurs ) ) ) ) ) ) . )
(ROOT (S (S (NP (DT The) (NN anode)) (VP (VBZ is) (NP (NP (DT the) (NN electrode)) (SBAR (WHPP (IN at) (WHNP (WDT which))) (S (NP (NN oxidation)) (VP (VBZ occurs))))))) (, ,) (CC and) (S (NP (DT the) (NN cathode)) (VP (VBZ is) (NP (NP (DT the) (NN electrode)) (SBAR (WHPP (IN at) (WHNP (WDT which))) (S (NP (NN reduction)) (VP (VBZ occurs))))))) (. .)))
The anode is the electrode at which oxidation occurs, and the cathode is the electrode at which reduction occurs.
(ROOT (S (NP (NP (DT The) (NN electrode)) (SBAR (WHPP (IN at) (WHNP (WDT which))) (S (NP (NN reduction)) (VP (VBZ occurs))))) (VP (VBZ is) (VP (VBN called) (NP (DT the) (NN cathode)))) (. .)))