Dictionary > Zeitgeber

Zeitgeber

Definition
noun, plural: zeitgebers
An external or environmental cue that helps regulate biological clock that drives biological rhythms
Supplement
Biological rhythms such as circadian rhythms, diurnal rhythms, ultradian rhythms, and infradian rhythms pertain to the synchronized cyclic pattern demonstrated by an organism as its response to a particular stimulus. Biological clock that synchronizes with biological rhythm may be endogenous or exogenous. An endogenous type is one in which the internal biological clock is the one that controls it. An exogenous type is one that which involves an external cue (i.e. zeitgeber).1 The term zeitgeber was coined by Jürgen Aschoff, a chronobiologist. He demonstrated how the internal biological clock drives biological rhythms.
Some of the examples of zeitgebers are light, temperature, eating or drinking patterns, etc. These external cues help the internal biological clock to be consistent with the rhythmic cycle. This process wherein the rhythmic events match the period to an environmental oscillation is called entrainment. For example, exposure to daylight (or blue light) at the wrong time may disrupt the quality of sleep since melatonin is produced usually at night (darkness). The duration of melatonin production is affected by the differing duration of nighttime. Melatonin is a hormone involved in sleep-wake timing and many other physiological mechanisms such as blood pressure regulation, seasonal reproduction, etc.
Word origin: German zeit ‎(“time”) + geber ‎(“giver”)
See also:

Reference(s):

1 Hedge, A. (2013). Biological Rhythms. Retrieved from ://ergo.human.cornell.edu/studentdownloads/dea3250pdfs/biorhythms.pdf


You will also like...

Control of body movement
Control of Body Movement

Some of the body movements can be controlled at will, others cannot. The body has a motor program, which is the pattern ..

Independent Assortment and Crossing Over
Independent Assortment and Crossing Over

This tutorial describes the independent assortment of chromosomes and crossing over as important events in meiosis. Read..

An artist depiction of a Precambrian multicellular life form.
The Evolution of Cell Organelles

The nucleus containing the genetic material, DNA, and the mitochondria, well-identified as the "powerhouse of the cell",..

A sperm cell fertilizing an ovum
Human Reproduction and Fertilization

For human species to obviate extinction, reproductive mature adults should be producing viable offspring in order to con..

Endemic Flora of New Zealand
New Zealand’s Unique Flora

If New Zealand has lots of unique animals, it's also got a whole lot of unique plants. Find out more about some of them,..

Flowers and tiny fruits of the pomegranate plant
Fruits, Flowers, and Seeds

This tutorial deals with the structure and function of flowers, fruits, and seeds. Also included here are the types of f..

Related Articles...

No related articles found

See all Related Topics