Other Definitions
biological clock (dict)
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Biological ClockA biological clock, also known as the circadian clock, enables an organism to anticipate periodical changes in their environment. Biological clocks generate biological rhythms on every biological level from gene expression to complex behaviour. Everyone who uses a computer knows that it contains a time mechanism, which has a fixed clock frequency. Following that way the human brain has also such a mechanism. It works at variable frequencies, between 20 and 180 Hz, depending of psychical state we have. Did you ever happened to wait for someone that is defering? Did you feel that time is drag on? Or in an exam, when the supervisor announced that you have only two minutes to finish your work, and you had something to write, didn't you fell that time passed too fast? Or didn't happened to you to impose yourself to wake in the morning at a precise time and to get down from bed some seconds before the clock buzzed? All that things, and temporal orientation of our body in the environment we live are the duty of Suprachiasmatic nucleii, which are located in anterior part of hypothalamus. Even if the Suprachiasmatic nucleii (SNC) cells are isolated from body they can maintain an independent circadian rhythm, beside the fact that SNC are controlled by hormenes, such as melathonine. See also: circadian clock
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