What is the Origin of Endogenous Biological Clock?

The term originates from chronobiology, combining endogenous (originating within the organism) and biological clock (a mechanism for time measurement). The master clock is anatomically located in the suprachiasmatic nucleus (SCN) of the hypothalamus. This neural structure utilizes a molecular feedback loop involving clock genes to maintain its rhythmicity.

What is the Mechanism of Endogenous Biological Clock?

At the molecular level, the SCN operates via an autoregulatory transcriptional-translational feedback loop involving core clock genes like Period (Per) and Cryptochrome (Cry). The cyclical expression and degradation of the proteins encoded by these genes generate the 24-hour oscillation. This central rhythm is then transmitted through neural and hormonal pathways to synchronize peripheral clocks in tissues like the liver and adrenal glands, thereby governing systemic hormone release patterns.

Endogenous Biological Clock ∞ Area

Endogenous Biological Clock

Meaning

The endogenous biological clock, formally known as the circadian system, is a self-sustaining internal timekeeping mechanism that regulates nearly all physiological and behavioral rhythms over an approximate 24-hour cycle. This central pacemaker coordinates sleep-wake cycles, hormone secretion, metabolic activity, and core body temperature. Its proper function is foundational to hormonal health, longevity, and disease prevention.