Zeitgeber (from German German (Deutsch, [ˈdɔʏtʃ] ) is a West Germanic language, thus related to and classified alongside English and Dutch. It is one of the world's major languages and the most widely spoken first language in the European Union. Globally, German is spoken by approximately 120 million native speakers and also by about 80 million non-native speakers for "time giver", synchronizer) is any exogenous (external) cue that synchronizes an organism's endogenous (internal) time-keeping system (clock) to the earth's 24-hour light/dark cycle. The strongest zeitgeber, for both plants and animals, is light. Other, non-photic, zeitgebers include temperature, social interactions, pharmacological manipulation and eating/drinking patterns. To maintain clock-environment synchrony, zeitgebers induce changes in the concentrations of the molecular components of the clock to levels consistent with the appropriate stage in the 24-hour cycle, a process termed entrainment In chronobiology, entrainment of a circadian system is the alignment of its own period and phase to the period and phase of an external rhythm. A common example is the entrainment of endogenous circadian rhythms to the daily light-dark cycle. Of the several possible cues, called zeitgeber (German for time-giver, synchronizer), which can contribute.[1]
The German term Zeitgeber came into the English language when Jürgen Aschoff, one of the founders of the field of chronobiology Chronobiology is a field of biology that examines periodic phenomena in living organisms and their adaptation to solar and lunar related rhythms. These cycles are known as biological rhythms. "Chrono" pertains to time and "biology" pertains to the study, or science, of life. The related terms chronomics and chronome have been, used it in the 1960s. It is now in common use in the scientific literature in this field.
See also
- Phase response curve A phase response curve illustrates the relationship between the timing and the effect of a treatment designed to affect circadian rhythms. Normally, the various rhythms will be in synchrony within an individual (human or animal), and sleep-wake is the most obvious of these rhythms. For humans, a treatment designed to affect circadian rhythms will
- Circadian rhythm A circadian rhythm is a roughly 24-hour cycle in the biochemical, physiological, or behavioural processes of living entities, including plants, animals, fungi and cyanobacteria . The term "circadian" comes from the Latin circa, "around", and diem or dies, "day", meaning literally "approximately one day". The
- Infradian rhythm
- Ultradian
- Melatonin Melatonin (pronounced /ˌmɛləˈtoʊnɪn/ ), also known chemically as N-acetyl-5-methoxytryptamine, is a naturally occurring compound found in animals, plants, and microbes. In animals, circulating levels of melatonin vary in a daily cycle, thereby regulating the circadian rhythms of several biological functions. Many biological effects of
- Suprachiasmatic nucleus The suprachiasmatic nucleus or nuclei, abbreviated SCN, is a tiny region on the brain's midline, situated directly above the optic chiasm. It is responsible for controlling circadian rhythms. The neuronal and hormonal activities it generates regulate many different body functions in a 24-hour cycle, using around 20,000 neurons or nuclei (SCN)
References
- ^ Toh, Kong Leong (August 2008). "Basic Science Review on Circadian Rhythm Biology and Circadian Sleep Disorders" (Review, Full Text, PDF). Annals Academy Med Singapore 37 (8): 662–8. http://www.annals.edu.sg/PDF/37VolNo8Aug2008/V37N8p662.pdf. Retrieved 2009-08-15.
Literature
- Aschoff J (1965) The phase-angle difference in circadian periodicity.In "Circadian Clocks" (J. Aschoff, ed.). North Holland Press, Amsterdam, p 262–278.
| This biology Biology is a natural science concerned with the study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy article is a stub. You can help Wikipedia by expanding it. |
Categories: Circadian rhythms | Sleep physiology Categories: Sleep | Physiology | Neurophysiology | German words and phrases Categories: Words and phrases by language | German language |
