A circadian rhythm ( /sɜrˈkeɪdiən/) is any biological process that displays an endogenous, entrainable oscillation of about 24 hours. These rhythms are driven by a circadian clock, and rhythms have been widely observed in plants, animals, fungi and cyanobacteria. The term circadian comes from the Latin circa, meaning "around" (or "approximately"), and diem or dies, meaning "day". The formal study of biological temporal rhythms, such as daily, tidal, weekly, seasonal, and annual rhythms, is called chronobiology. Although circadian rhythms are endogenous ("built-in", self-sustained), they are adjusted (entrained) to the local environment by external cues called zeitgebers, commonly the most important of which is daylight.
Read more about Circadian Rhythm: History, Criteria, Origin, Importance in Animals, In Plants, Biological Clock in Mammals, Light and The Biological Clock, Enforced Longer Cycles, Human Health
Famous quotes containing the word rhythm:
“Who among us has not, in moments of ambition, dreamt of the miracle of a form of poetic prose, musical but without rhythm and rhyme, both supple and staccato enough to adapt itself to the lyrical movements of our souls, the undulating movements of our reveries, and the convulsive movements of our consciences? This obsessive ideal springs above all from frequent contact with enormous cities, from the junction of their innumerable connections.”
—Charles Baudelaire (1821–1867)