Please join StudyMode to read the full document. Discuss the role of endogenous pacemakers and exogenous zeitgebers in biological rhythms A rhythm is something that is regularly repeated e. These rhythms are repeated over different intervals and they are governed by both internal endogenous and external exogenous factors. The Suprachiasmitic Nucleus SCN is a small group of cells in the hypothalamus; it lies just above the optic chasm so it can gain input directly from the eyes, and therefore the rhythm can be reset by the amount of light entering the eye.
Discuss the Role of Endogenous Pacemakers and Exogenous Zeitgebers. Essay Example
Describe and Evaluate Circadian Rhythms Example | Graduateway
Please join StudyMode to read the full document. Endogenous pacemakers and exogenous zeitgebers are used to control biological rhythms. Biological rhythms are controlled by environmental factors such as light, temperature and food availability; these are known as exogenous external zeitgebers. However biological organisms are complex systems, where many different processes are taking place.
Please join StudyMode to read the full document. Describe in detail endogenous pacemakers - suprachiasmatic nucleus SCN in the hypothalamus, SCN obtains information about light from the eye via the optic nerve, happens even when eyes are shut, as light penetrates the eyelids. If endogenous clock is running slowly, morning light automatically shifts the clock ahead, making the rhythm correct with the world outside again. SCN- pair of structures- one in each hemisphere of the brain, and each of these is divided into a ventral and dorsal SCN.
Endogenous pacemakers are internal mechanisms that govern biological rhythms, in particular, the circadian sleep-wake cycle. Although endogenous pacemakers are internal biological clocks, they can be altered and affected by the environment. For example, although the circadian sleep-wave cycle will continue to function without natural cues from light, research suggests that light is required to reset the cycle every 24 hours. The suprachiasmatic nucleus SCN , which lies in the hypothalamus , is the main endogenous pacemaker or master clock. It controls other biological rhythms, as it links to other areas of the brain responsible for sleep and arousal.