BI 230 - L15(Biological Rhythms)

Diurnal

Active during the day.

Nocturnal

Active during the night.

Crepuscular

Active at dawn and dusk.

Jet lag

Physiological and behavioral responses to jet travel across time zones.

Chronobiology

The scientific study of biological clocks and their associated rhythms.

Zeitgeber

An external or environmental cue that helps regulate the biological rhythms of an organism.

Endogenous biological clocks

Internal biological mechanisms that generate rhythms regardless of external cues.

Exogenous factors

External stimuli that influence biological rhythms.

Circadian rhythms

Biological rhythms that cycle approximately every 24 hours.

Ultradian rhythms

Biological rhythms that occur more than once within a 24-hour cycle.

Infradian rhythms

Biological rhythms that occur less than once a day.

Adaptive function

The role biological clocks play in synchronizing activities of animals with their environment.

SCN (Suprachiasmatic Nuclei)

The brain region critical for circadian rhythm generation in mammals.

Melatonin

A hormone with strong circadian rhythms of secretion, influenced by light exposure.

Circannual rhythms

Biological processes aligned with annual cycles, often influenced by seasonal changes.

Phase-response curves

Graphic representations illustrating how a zeitgeber affects biological rhythm timing based on phase.

Entrainment

The synchronization of endogenous biological rhythms with environmental cues.

Hibernation

A state of significantly decreased metabolic activity during winter months, often regulated by circannual rhythms.

Hormonal modulation

The influence of hormones on the timing and stability of biological rhythms.

Photoperiodism

The physiological reaction of organisms to the length of day or night.

Neuroendocrine

Referring to the interactions between the nervous system and the endocrine system.