( ( ( ( CROSSING OVER ) ( ( The exchange ) ( of ( corresponding segments ) ) ) ) ( between ( chromatids ( of ( paired ( ( -LRB- ( homologous -RRB- ) ) chromosomes ) ) ) ) ) ) ; )
(ROOT (NP (NP (NNP CROSSING) (NNP OVER)) (NP (NP (DT The) (NN exchange)) (PP (IN of) (NP (JJ corresponding) (NNS segments)))) (PP (IN between) (NP (NP (NNS chromatids)) (PP (IN of) (NP (JJ paired) (PRN (-LRB- -LRB-) (NP (NNP homologous)) (-RRB- -RRB-)) (NNS chromosomes))))) (: ;)))
CROSSING OVER The exchange of corresponding segments between chromatids of paired (homologous) chromosomes;
(ROOT (S (NP (NNP Crossing-over)) (VP (VBZ is) (NP (NP (DT the) (NN term)) (PP (IN for) (NP (NP (DT the) (NN exchange)) (PP (IN of) (NP (NP (JJ genetic) (NN material)) (PP (IN between) (NP (NP (JJ non-sister) (NNS chromatids)) (PP (IN of) (NP (JJ homologous) (NNS chromosomes))))))))))) (. .)))