( ( ( The ( various shapes ) ) ( of cells ) ) ( ( are ( controlled ( by ( the cytoskeleton ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (JJ various) (NNS shapes)) (PP (IN of) (NP (NNS cells)))) (VP (VBP are) (VP (VBN controlled) (PP (IN by) (NP (DT the) (NN cytoskeleton))))) (. .)))
The various shapes of cells        are controlled by the cytoskeleton.
(ROOT (S (NP (DT The) (NN cytoskeleton)) (VP (VBZ is) (NP (NP (DT the) (NN skeleton)) (PP (IN of) (NP (DT the) (NN cell))))) (. .)))