( ( ( Membrane-bound organelles ) ( once autonomous ) ) ( prokaryotes . ) )
(ROOT (S (NP (NP (JJ Membrane-bound) (NNS organelles)) (ADJP (RB once) (JJ autonomous))) (VP (VBZ prokaryotes)) (. .)))
Membrane-bound organelles once autonomous prokaryotes.
(ROOT (S (NP (NP (JJ Prokaryotic) (NNS cells) (POS ')) (NNS organelles)) (ADVP (RB because) (RB not)) (VP (VBD membrane-bound)) (. .)))