Circadian cycles: the rhythms of life.
There are numerous biological cycles, such as life and death and seasonal variations, called circannual rhythms. The skin's behavior also correlates with these biological rhythms. Circadian and other variations may have important implications for skin treatment and future research.
D002468:Cell Physiological Phenomena; D002940:Circadian Rhythm / Q000502:physiology*; D006801:Humans; D012867:Skin / Q000166:cytology; D012879:Skin Physiological Phenomena