( ( The ( human cell ) ) ( ( ( ( contains ( ( 23 pairs ) ( of chromosomes ) ) ) , ) ( with ( ( each parent ) ( ( contributing ( one chromosome ) ) ( to ( each pair ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (JJ human) (NN cell)) (VP (VBZ contains) (NP (NP (CD 23) (NNS pairs)) (PP (IN of) (NP (NNS chromosomes)))) (, ,) (PP (IN with) (NP (NP (DT each) (NN parent)) (VP (VBG contributing) (NP (CD one) (NN chromosome)) (PP (TO to) (NP (DT each) (NN pair))))))) (. .)))
The human cell contains 23 pairs of chromosomes, with each parent contributing one chromosome to each pair.
(ROOT (S (NP (DT A) (JJ normal) (JJ human) (NN liver) (NN cell)) (VP (VBZ has) (NP (NP (CD 23) (NNS pairs)) (PP (IN of) (NP (NNS chromosomes))))) (. .)))