Dictionary > Ultradian rhythm

Ultradian rhythm

Definition
noun, plural: ultradian rhythms
A biological rhythm that is repeated throughout a 24-hour circadian day and therefore has a shorter period and higher frequency than a circadian rhythm
Supplement
Biological 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). There are the different types of biological rhythms: circadian rhythms, diurnal rhythms, ultradian rhythms, and infradian rhythms.1
An ultradian rhythm has a shorter period and higher frequency than a circadian rhythm. The cycle is repeated throughout a 24-hour circadian day. This is in contrast to the infradian rhythm wherein the recurrent period occurs longer than a day. In ultradian rhythm, the cycle has a period shorter than a day but longer than an hour.2 Examples of ultradian rhythms are blood circulation, pulse, heart rate, thermoregulation, blinking, micturition, appetite, arousal, etc.
See also:

Reference(s):

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

2 “Ultradian, adj.” Oxford English Dictionary. Retrieved from ://www.oed.com.


You will also like...

Gene Pool and Speciation
The Gene Pool and Population Genetics

According to Charles Darwin's theory of natural selection, preferable genes are favored by nature in the gene pool, and ..

primitive arthropods
Arthropods

The arthropods were assumed to be the first taxon of species to possess jointed limbs and exoskeleton, exhibit more adva..

Disturbance on a still water
Abiotic Factors – Water Conditions

A still body of water may be disturbed by a variety of factors. One of them is wind. In fact, it is considered as the pr..

Bryophytes
Bryophytes

Bryophytes (nonvascular plants) are a plant group characterized by lacking vascular tissues. They include the mosses, th..

Mātauranga Māori and Science Collaboration
Mātauranga Māori and Science

Mātauranga Māori is the living knowledge system of the indigenous people of New Zealand, including the relationships t..

Human Neurology
Human Neurology

Human Neurology deals essentially with the nervous system of humans. It also features the various theories put forward b..