( Gametophytes ( ( ( ( produce ( gametes ( , ( ( egg and ) sperm ) ) ) ) , ) ( by mitosis ) ) . ) )
(ROOT (S (NP (NNS Gametophytes)) (VP (VBP produce) (NP (NNS gametes) (, ,) (NN egg) (CC and) (NN sperm)) (, ,) (PP (IN by) (NP (NNS mitosis)))) (. .)))
Gametophytes produce gametes, egg and sperm, by mitosis.
(ROOT (S (NP (DT The) (JJ haploid) (NN gametophyte)) (VP (VBZ produces) (NP (NNS gametes)) (PP (IN through) (NP (NNS mitosis)))) (. .)))