( ( S-phase ( -LRB- ( ( synthesis phase ) -RRB- ) ) ) ( ( is ( ( ( ( the part ) ( of ( ( the ( cell cycle ) ) ( ( in which ) ( DNA ( is replicated ) ) ) ) ) ) , ) ( occurring ( between ( G1 ( phase ( and ( G2 phase ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (NNP S-phase)) (PRN (-LRB- -LRB-) (NP (NN synthesis) (NN phase)) (-RRB- -RRB-))) (VP (VBZ is) (NP (NP (DT the) (NN part)) (PP (IN of) (NP (NP (DT the) (NN cell) (NN cycle)) (SBAR (WHPP (IN in) (WHNP (WDT which))) (S (NP (NNP DNA)) (VP (VBZ is) (VP (VBN replicated))))))) (, ,) (VP (VBG occurring) (PP (IN between) (NP (JJ G1) (NN phase) (CC and) (NN G2) (NN phase)))))) (. .)))
S-phase (synthesis phase) is the part of the cell cycle in which DNA is replicated, occurring between G1 phase and G2 phase.
(ROOT (S (PP (IN During) (NP (NP (DT the) (NN synthesis) (NN phase)) (PP (IN in) (NP (DT the) (NN cell) (NN cycle))))) (, ,) (NP (NN dna) (NN replication)) (VP (VBZ occurs)) (. .)))