( ( ( Sexual reproduction ) ( with ( ( gametes and ) fertilization ) ) ) ( ( produces ( a ( diploid ( sporophyte generation ) ) ) ) . ) )
(ROOT (S (NP (NP (JJ Sexual) (NN reproduction)) (PP (IN with) (NP (NNS gametes) (CC and) (NN fertilization)))) (VP (VBZ produces) (NP (DT a) (JJ diploid) (NN sporophyte) (NN generation))) (. .)))
Sexual reproduction with gametes and  fertilization produces a diploid sporophyte generation.
(ROOT (S (NP (NP (JJ Sexual) (NN reproduction)) (PP (IN with) (NP (NNS gametes) (CC and) (NN fertilization)))) (VP (VBZ produces) (NP (JJ diploid) (NN sporophyte))) (. .)))