Internal clock

circadian rhythm

A daily rhythmic activity cycle, based on 24-hour intervals, that is exhibited by many organisms.

circadian rhythm (s

r-k

A daily cycle of biological activity based on a 24-hour period and influenced by regular variations in the environment, such as the alternation of night and day. Circadian rhythms include sleeping and waking in animals, flower closing and opening in angiosperms, and tissue growth and differentiation in fungi. See also biological clock.

A Closer Look The circadian rhythm, present in humans and most other animals, is generated by an internal clock that is synchronized to light-dark cycles and other cues in an organism's environment. This internal clock accounts for waking up at the same time every day even without an alarm clock. It also causes nocturnal animals to function at night when diurnal creatures are at rest. Circadian rhythms can be disrupted by changes in daily schedule. Biologists have observed that birds exposed to artificial light for a long time sometimes build nests in the fall instead of the spring. While the process underlying circadian rhythm is still being investigated, it is known to be controlled mainly by the release of hormones. In humans, the internal clock is located within the brain's hypothalamus and pineal gland, which releases melatonin in response to the information it receives from photoreceptors in the retina. Nighttime causes melatonin secretion to rise, while daylight inhibits it. Even when light cues are absent, melatonin is still released in a cyclical manner.

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biological clock biological time biorhythm circadian fatigue jet lag photoreceptor pineal gland scotophil tiredness weariness			So circadian refers to the 24 hour internal clock that everyone has. Get A Good Night?s Sleep with Auto Circadian Meditation by Susan Masters / Self Improvement community So if you are missing something from your daily routine like smoking or excessive food, your biorhythms or internal clock will let you know. Circadian Meditation Curbs Nicotine Cravings by Susan Masters / Food/cooking/nutrition community There is a bug in the internal clock driver causing the 30GB device to improperly handle the last day of a leap year," Microsoft said. Leap year bug zaps Zune music players by AFP / AFP American Edition			intermodal intermodal support equipment intermodal systems Intermodillion intermodulation intermolecular intermontane intermountain Intermundane Intermundian Intermural Intermure Intermuscular Intermutation Intermutual intern internal internal angle Internal angles internal audience internal auditor internal auditory artery internal auditory vein internal carotid artery internal cerebral vein Internal clock internal combustion internal control internal defense and development internal drive internal ear internal energy Internal gear internal iliac artery internal iliac vein internal information internal jugular vein internal market internal maxillary artery internal medicine internal organ internal radiation internal rate of return internal representation internal resistance internal respiration internal revenue internal revenue agent Internal Revenue Service internal rhyme internal secretion			internal carotid artery internal carotid artery arteritis internal carotid artery arteritis internal carotid artery arteritis internal carotid artery arteritis Internal Carotid Artery Blood Flow Internal Carotid Back Pressure Internal Carotid Blood Flow Internal Carotid Diastolic Velocity Internal Carotid Flow Velocity internal carotid nerve internal carotid nerve Internal carotid nerve plexus Internal Carotid Ophthalmic Artery Internal Carotid Peak Systolic Velocity internal carotid plexus Internal Carotid Systolic Velocity internal cast Internal Cerebral Artery internal cerebral vein internal cerebral vein Internal cerebral veins Internal cerebral veins internal cervical os Internal Change Control Board Internal Change Review Board Internal Channel Service Unit Internal Character Encoding Internal Civil Rights Branch Internal Class Implementation Internal clock internal clocking internal cloud Internal Clutter Motion Internal coat Internal coat internal combustion internal combustion internal combustion Internal combustion engine Internal combustion engine Internal combustion engine Internal Combustion Engine Division Internal Combustion Engine Powered Materiel Internal Combustion Engine Repair Ship Internal Combustion Engine Research Group Internal Combustion Engine Vehicle Internal combustion engines Internal Combustion Reciprocating Piston Engines internal command Internal Commercial Intrusion Detection System Internal communication Internal Communication Assessment Group Internal Communication Circuit Internal communications Internal communications Internal Communications Coordinator Internal Communications Management System Internal Communications Processor Internal Communications Workgroup Internal compiler error

circadian rhythm (redirected from Internal clock)

circadian rhythm
(redirected from Internal clock)