That controls sleep and wakefulness. It is the body's natural clock. It is a biological rhythm or cycle of approximately 24 hours.
Circadian Rhythm.
Circadian
Circadian
Each 24-hour cycle of and night is called a(n) zeitgebers!
It is called the Circadian Rhythm.
circadian rhythm
the circadian rhythm
Probably your circadian rhythm prevents you. Circadian rhythm is a person's biological clock; regular bodily rhythms (for example temperature or in your example wakefullness and tiredness) that occur on a 24 hour cycle.
http://www.answers.com/topic/body-rhythm-physiology
A daily cycle is a "circadian rhythm" that's 15 letters and one space.
The term circadian comes from the Latin words circa which means "around" and dies which means "day". The term circadian rhythm refers to the biochemical processes of an organism that occur over the duration of 24 hours. A circadian rhythm disorder is any disruption in a person's circadian rhythm.
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