( ( ( ( ( Spermatogenesis results ) ( in ( ( the production ) ( from ( each spermato ) ) ) ) ) - ) ( gonium ( of ( ( ( four ( similar ( sperm cells ) ) ) , ) ( ( all ( of which ) ) ( ( ( are functional ) , ) ( while ( oogenesis ( results ( in ( ( the formation ) ( ( ( from ( ( each oogonium ) ( of ( ( ( ( only ( one ( large cell ) ) ) , ) ( the ( egg cell ) ) ) , ) ) ) ) and ) ( of ( ( ( three ( small ( nonfunctional cells ) ) ) or ) ( polar bodies ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) . )
(ROOT (NP (NP (NP (JJ Spermatogenesis) (NNS results)) (PP (IN in) (NP (NP (DT the) (NN production)) (PP (IN from) (NP (DT each) (NN spermato)))))) (: -) (NP (NP (NN gonium)) (PP (IN of) (NP (NP (CD four) (JJ similar) (NN sperm) (NNS cells)) (, ,) (SBAR (WHNP (DT all) (WHPP (IN of) (WHNP (WDT which)))) (S (VP (VBP are) (ADJP (JJ functional)) (, ,) (SBAR (IN while) (S (NP (NNS oogenesis)) (VP (VBZ results) (PP (IN in) (NP (NP (DT the) (NN formation)) (PP (PP (IN from) (NP (NP (DT each) (NN oogonium)) (PP (IN of) (NP (NP (RB only) (CD one) (JJ large) (NN cell)) (, ,) (NP (DT the) (NN egg) (NN cell)) (, ,))))) (CC and) (PP (IN of) (NP (NP (CD three) (JJ small) (JJ nonfunctional) (NNS cells)) (CC or) (NP (JJ polar) (NNS bodies)))))))))))))))) (. .)))
Spermatogenesis results in the production from each spermato-  gonium of four similar sperm cells, all of which are functional, while  oogenesis results in the formation from each oogonium of only one large  cell, the egg cell, and of three small nonfunctional cells or polar  bodies.
(ROOT (S (NP (CD One) (JJ large) (NNS eggs)) (VP (VBP are) (VP (VBN generated) (PP (IN during) (NP (NNS oogenesis))))) (. .)))