( Prokaryotes ( ( are ( ( single-celled organisms ) ( that ( ( ( lack ( a ( membrane-bound nucleus ) ) ) and ) ( usually ( lack ( ( membrane-bound organelles ) ( -LRB- ( ( ( mitochondria , ) chloroplasts ) -RRB- ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNS Prokaryotes)) (VP (VBP are) (NP (NP (JJ single-celled) (NNS organisms)) (SBAR (WHNP (WDT that)) (S (VP (VP (VBP lack) (NP (DT a) (JJ membrane-bound) (NN nucleus))) (CC and) (VP (ADVP (RB usually)) (VBP lack) (NP (NP (JJ membrane-bound) (NNS organelles)) (PRN (-LRB- -LRB-) (NP (NP (NN mitochondria)) (, ,) (NP (NNS chloroplasts))) (-RRB- -RRB-))))))))) (. .)))
Prokaryotes are single-celled organisms that lack a membrane-bound nucleus and usually lack membrane-bound organelles (mitochondria, chloroplasts).
(ROOT (S (NP (NNS Prokaryotes)) (VP (VBP are) (NP (NP (JJ single-celled) (CC or) (JJ colonial) (NNS organisms)) (SBAR (WHNP (WDT that)) (S (VP (VBP do) (RB not) (VP (VB have) (VP (VBN membranebound) (NP (NNS nuclei))))))))) (. .)))