( ( ( The result ) ( of oogenesis ) ) ( , ( therefore ( , ( ( is ( to ( ( produce ( ( ( one ( ( large ( , functional ) ) ( egg cell ) ) ) and ) ( ( either ( ( two or ) three ) ) ( polar bodies ) ) ) ) ( ( depending upon ) ( ( ( whether or ) not ) ( ( the ( first ( polar body ) ) ) ( undergoes division ) ) ) ) ) ) ) . ) ) ) ) )
(ROOT (S (NP (NP (DT The) (NN result)) (PP (IN of) (NP (NNS oogenesis)))) (, ,) (ADVP (RB therefore)) (, ,) (VP (VBZ is) (S (VP (TO to) (VP (VB produce) (NP (NP (NP (CD one)) (NP (ADJP (JJ large) (, ,) (JJ functional)) (NN egg) (NN cell))) (CC and) (NP (NP (CC either) (CD two) (CC or) (CD three)) (NP (JJ polar) (NNS bodies)))) (S (VP (VBG depending) (PRT (RP upon)) (SBAR (IN whether) (CC or) (RB not) (S (NP (DT the) (JJ first) (JJ polar) (NN body)) (VP (VBZ undergoes) (NP (NN division))))))))))) (. .)))
The result of oogenesis, therefore, is to produce one large,  functional egg cell and either two or three polar bodies depending upon whether or not the first polar body undergoes division.
(ROOT (S (NP (CD One) (JJ large) (NNS eggs)) (VP (VBP are) (VP (VBN generated) (PP (IN during) (NP (NNS oogenesis))))) (. .)))