( ( ( ( ( Circadian rhythms ) , ) ( like ( ( the ( sleep-wake cycles ) ) ( discussed later ) ) ) ) , ) ( ( are ( generated ( by ( ( an ( internal clock ) ) ( that ( is ( ( synchronized ( to ( light-dark cycles ) ) ) ( in ( ( ( the environment ) and ) ( other ( daily cues ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (NN Circadian) (NNS rhythms)) (, ,) (PP (IN like) (NP (NP (DT the) (JJ sleep-wake) (NNS cycles)) (VP (VBN discussed) (ADVP (RB later))))) (, ,)) (VP (VBP are) (VP (VBN generated) (PP (IN by) (NP (NP (DT an) (JJ internal) (NN clock)) (SBAR (WHNP (WDT that)) (S (VP (VBZ is) (VP (VBN synchronized) (PP (TO to) (NP (JJ light-dark) (NNS cycles))) (PP (IN in) (NP (NP (DT the) (NN environment)) (CC and) (NP (JJ other) (JJ daily) (NNS cues)))))))))))) (. .)))
Circadian rhythms, like the sleep-wake cycles discussed later, are generated by an internal clock that is synchronized to light-dark cycles in the environment and other daily cues.
(ROOT (S (NP (NN Circadian) (NNS rhythms)) (VP (VBZ is) (NP (NP (DT the) (NN term)) (PP (IN for) (NP (NP (JJ daily) (NNS cycles)) (PP (IN of) (NP (NN behavior)))))) (, ,) (PP (IN like) (NP (DT the) (JJ sleep-wake) (NN cycle)))) (. .)))