( ( ( ( A ( haploid ( germ cell ) ) ) , ) ( ( ( ( either maternal ) ( -LRB- ( ovum -RRB- ) ) ) or ) ( paternal ( -LRB- ( sperm -RRB- ) ) ) ) ) . )
(ROOT (NP (NP (DT A) (JJ haploid) (NN germ) (NN cell)) (, ,) (NP (NP (NP (DT either) (NN maternal)) (PRN (-LRB- -LRB-) (NP (NNP ovum)) (-RRB- -RRB-))) (CC or) (NP (NP (NN paternal)) (PRN (-LRB- -LRB-) (NP (NN sperm)) (-RRB- -RRB-)))) (. .)))
A haploid germ cell, either maternal (ovum) or paternal (sperm).
(ROOT (S (SBAR (IN While) (S (NP (NNS spermatogenesis)) (VP (VBZ produces) (NP (CD four) (JJ haploid) (NN sperm) (NNS cells))))) (, ,) (NP (NNS oogenesis)) (VP (VBZ produces) (NP (CD one) (JJ mature) (NN ovum))) (. .)))