( ( Cells ( propagate ( by ( repeating ( ( ( these ( four phases ) ) and ) ( this ( 4-phase cycle ) ) ) ) ) ) ) ( ( is ( ( ( called ` ) ( Cell Cycle ) ) ' ) ) . ) )
(ROOT (S (NP (NP (NNS Cells)) (ADJP (JJ propagate) (PP (IN by) (S (VP (VBG repeating) (NP (NP (DT these) (CD four) (NNS phases)) (CC and) (NP (DT this) (JJ 4-phase) (NN cycle)))))))) (VP (VBZ is) (VP (VBN called) (`` `) (NP (NNP Cell) (NNP Cycle)) ('' '))) (. .)))
Cells propagate by repeating these four phases and this 4-phase cycle is called 'Cell Cycle'.
(ROOT (S (NP (NNS Cells)) (VP (VBP have) (NP (CD four) (NNS cycles))) (. .)))