( ( ( ( ( All ( flowering plants ) ) ( produce flowers ) ) and ) ( ( if ( they ( are ( sexually reproductive ) ) ) ) ( , ( they ( produce ( a ( diploid ( ( ( zygote and ) triploid ) endosperm ) ) ) ) ) ) ) ) . )
(ROOT (S (S (NP (DT All) (VBG flowering) (NNS plants)) (VP (VBP produce) (NP (NNS flowers)))) (CC and) (S (SBAR (IN if) (S (NP (PRP they)) (VP (VBP are) (NP (RB sexually) (JJ reproductive))))) (, ,) (NP (PRP they)) (VP (VBP produce) (NP (DT a) (JJ diploid) (ADJP (JJ zygote) (CC and) (JJ triploid)) (NN endosperm)))) (. .)))
All flowering plants produce flowers and if they are sexually reproductive, they produce a diploid zygote and triploid endosperm .
(ROOT (S (NP (NP (DT A) (NN method)) (PP (IN of) (NP (NP (JJ sexual) (NN reproduction)) (SBAR (WHNP (WDT that)) (S (VP (VBZ occurs) (PP (IN in) (NP (NNS plants))))))))) (VP (MD can) (VP (VB be) (VP (VBN described) (SBAR (IN as) (S (NP (NNS seeds)) (VP (VBP are) (VP (VBN produced) (PP (IN from) (NP (NP (DT the) (NN flower)) (PP (IN of) (NP (DT the) (NN plant)))))))))))) (. .)))