( ( This ( internal clock ) ) ( ( controls ( ( a variety ) ( of ( ( ( daily ( biochemical ( and ( behavioral cycles ) ) ) ) ( -- ( ( including ( fluctuations ( in ( ( sleep and ) wakefulness ) ) ) ) -- ) ) ) ( that ( ( are collectively ) ( called ( circadian rhythms ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT This) (JJ internal) (NN clock)) (VP (VBZ controls) (NP (NP (DT a) (NN variety)) (PP (IN of) (NP (NP (JJ daily) (NN biochemical) (CC and) (JJ behavioral) (NNS cycles)) (PRN (: --) (PP (VBG including) (NP (NP (NNS fluctuations)) (PP (IN in) (NP (NN sleep) (CC and) (NNS wakefulness))))) (: --)) (SBAR (WHNP (WDT that)) (S (VP (VBP are) (ADVP (RB collectively)) (VP (VBN called) (NP (NN circadian) (NNS rhythms)))))))))) (. .)))
This internal clock controls a variety of daily biochemical and behavioral cycles -- including fluctuations in sleep and wakefulness -- that are collectively called circadian rhythms.
(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)))) (. .)))