( ( ( ( ( Cell division ) ( ( occurs ( after ( ( a ( ( ( male and ) female ) ( sex cell ) ) ) ( have united ) ) ) ) ( -LRB- ( fertilization -RRB- ) ) ) ) and ) ( ( the ( resulting zygote ) ) ( divides ( into ( two cells ) ) ) ) ) . )
(ROOT (S (S (NP (JJ Cell) (NN division)) (VP (VBZ occurs) (SBAR (IN after) (S (NP (DT a) (ADJP (NN male) (CC and) (JJ female)) (NN sex) (NN cell)) (VP (VBP have) (VP (VBN united))))) (PRN (-LRB- -LRB-) (VB fertilization) (-RRB- -RRB-)))) (CC and) (S (NP (DT the) (VBG resulting) (NN zygote)) (VP (VBZ divides) (PP (IN into) (NP (CD two) (NNS cells))))) (. .)))
Cell division occurs after a male and female sex cell have united (fertilization) and the resulting zygote divides into two cells.
(ROOT (S (PP (IN After) (NP (NN fertilization))) (, ,) (NP (DT a) (NN zygote)) (VP (VBZ forms) (PP (IN into) (NP (CD two) (NNS cells)))) (. .)))