Definition
The sequence of molecular, biochemical, physiological and behavioral changes that occur over the course of a single near-24 h period within an organism.
Characteristics
A circadian cycle defines the sequence of molecular, biochemical, physiological and behavioral changes that occur over the course of a single near-24 h period within an organism. Presumably, these characteristic near-24 h temporal programs represent an adaptation to existence on a planet where the repetitive cycle of light and darkness may well be the most ancient and most persistent event under which all life has evolved. The fundamental nature of these 24-h rhythms is evident from their wide range of expression; they are present in organisms across all phyla. Circadian oscillations in organismic physiology and behavior allow anticipation of daily environmental change. The capacity to anticipate, and subsequently, to prepare for change promotes reproductive fitness, thereby enhancing survival of the species.
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References
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© 2009 Springer-Verlag GmbH Berlin Heidelberg
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Tischkau, S. (2009). Circadian Cycle. In: Binder, M.D., Hirokawa, N., Windhorst, U. (eds) Encyclopedia of Neuroscience. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-29678-2_1046
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DOI: https://doi.org/10.1007/978-3-540-29678-2_1046
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Publisher Name: Springer, Berlin, Heidelberg
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