What is the Origin of Physiological Chronometer?

The term synthesizes "physiological," relating to the normal functions of an organism, and "chronometer," a device for measuring time, derived from the Greek chronos (time) and metron (measure). It is a descriptive concept central to chronobiology, highlighting the body's intrinsic, genetically encoded timekeeping system.

What is the Mechanism of Physiological Chronometer?

The chronometer is based on a set of 'clock genes' and their protein products that operate in a self-sustaining transcriptional-translational feedback loop within individual cells. Environmental cues, primarily light, reset the master SCN clock, which then transmits signals via neural and hormonal pathways to synchronize the timing of sleep-wake cycles, core body temperature, and the diurnal secretion of hormones like cortisol and melatonin.

Physiological Chronometer ∞ Area

Physiological Chronometer

Meaning

A conceptual and functional term referring to the aggregate of internal biological timing mechanisms that regulate the cyclical, rhythmic expression of virtually all physiological processes in the human body. The Suprachiasmatic Nucleus (SCN) in the hypothalamus acts as the master clock, coordinating peripheral clocks in organs to maintain circadian and other rhythms. This chronometer is the foundation of health, ensuring that metabolic and hormonal events occur at the optimal time of day.