( ( ( The ( last part ) ) ( of ( sperm development ) ) ) ( ( ( involves transformation ) ( into ( ( ( ( ( a cell ) ( with ( ( ( a head ) , ) ( which ( contains ( the ( ( nucleus and ) DNA ) ) ) ) ) ) ) , ) and ) ( ( ( a ( filamentous tail ) ) , ) ( which ( ( propels ( the sperm ) ) forward ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (JJ last) (NN part)) (PP (IN of) (NP (NN sperm) (NN development)))) (VP (VBZ involves) (NP (NN transformation)) (PP (IN into) (NP (NP (NP (DT a) (NN cell)) (PP (IN with) (NP (NP (DT a) (NN head)) (, ,) (SBAR (WHNP (WDT which)) (S (VP (VBZ contains) (NP (DT the) (NN nucleus) (CC and) (NN DNA)))))))) (, ,) (CC and) (NP (NP (DT a) (JJ filamentous) (NN tail)) (, ,) (SBAR (WHNP (WDT which)) (S (VP (VBZ propels) (NP (DT the) (NN sperm)) (ADVP (RB forward))))))))) (. .)))
The last part of sperm development involves transformation into a cell with a head, which contains the nucleus and DNA, and a filamentous tail, which propels the sperm forward.
(ROOT (S (NP (NP (DT The) (NN head)) (PP (IN of) (NP (DT the) (NN sperm)))) (VP (VBZ contains) (NP (DT the) (NN nucleus))) (. .)))
The head of the sperm contains the nucleus.