circadian rhythm

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circadian rhythm:

see rhythm, biologicalrhythm, biological,
or biorhythm,
cyclic pattern of physiological changes or changes in activity in living organisms, most often synchronized with daily, monthly, or annual cyclical changes in the environment.
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circadian rhythm

[sər′kād·ē·ən ′rith·əm]
A self-sustained cycle of physiological changes that occurs over an approximately 24-hour cycle, generally synchronized to light-dark cycles in an organism's environment.
References in periodicals archive ?
In his study, he turned off all the internal clocks in a group of mice.
Also avoid large meals before going to sleep, since your metabolism's processing of the food will throw off your internal clock. And while alcohol is a depressant that can make you fall asleep, the metabolizing of the alcohol can lead to disruptions of the important second half of your sleep cycle.
This strongly suggests there is some internal clock mechanism keeping the roosters crowing on time -- otherwise, one would expect the roosters kept in 24-hour dim light conditions to crow erratically.
Most mice sleep, eat, and exercise on a predictable 24-hour cycle, thanks to their precise internal clocks. But mice fed a fatty diet have trouble sticking to their schedule, new research shows.
Inhibiting photosynthesis, for example, slowed the plants internal clock by between 2 and 3 hours.
Johnson and other scientists want to look at the effects of circadian rhythm disruption in human subjects before dishing out authoritative tips on how to eat in harmony with one's internal clock.
People who have a hard time waking in the morning because their bodies' internal clocks are out of syne with their sleep schedules are said to have "social jet lag" Researchers in Europe have determined that the phenomenon strongly correlates with smoking.
He diagnosed her with delayed sleepphase syndrome, a condition in which the body's internal clock fails to synchronize appropriately with Earth's day-night cycle, which changes a few minutes each day.
To make this discovery, Coomans and colleagues exposed mice to constant light, which disturbed their normal internal clock function, and observed a gradual degradation of their bodies' internal clocks until it reached a level that normally occurs when aging.
One theory has it that such long-term growth cycles operate on an internal clock that's independent of the seasons or temperature.
Washington, January 18 ( ANI ): New research has shown how the fruit fly's internal clock is affected by the daily changes in temperature.
That was your internal clock jolting you awake just when you wished you could crawl under the covers.

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