Homeostasis: Feedback and Body

1616 WordsAug 3, 20107 Pages
Homeostasis is a simple term which holds a large significance in the functionality of the human body. This essay will discuss and define this term. Explanation as to why homeostasis is important to be maintained and two examples of homeostasis relevant to its control mechanism will be stated in this essay as well. The word homeostasis was first introduced by Walter B. Cannon, an American physiologist, to describe the body’s ability to maintain relative stability of its internal conditions even though there were constant changes in the surroundings outside. (Marieb & Hoehn, 2007). Thus, homeostasis is utterly defined as “the condition of equilibrium in the body’s internal environment due to the constant interaction of the body’s many…show more content…
The regulation of body temperature is one such mechanism to restore homeostasis. The human body temperature is controlled by the thermoregulatory centre in the hypothalamus which is located in the middle of the brain. Inputs are received form two sets of thermo-receptors. The first is the receptors in the hypothalamus itself which monitors the temperature of blood passing through the brain - the core temperature, and the second is the receptors in the skin which monitors external temperature. Both sets of the information are vital and are received alongside each other so that the appropriate adjustments can be made by the body. The thermoregulatory center sends impulses to several different effectors so body temperature can be adjusted swiftly. In the case of body temperature increasing (e.g. exercising or hot weather), the heat loss centre in the hypothalamus is triggered. The thermostat in the hypothalamus activates cooling mechanisms. Output is send to the effectors such as the smooth muscles (arterioles in the skin), and the sweat glands. Muscles relax causing vasodilatation – skin blood vessels dilate. Additional heat is carried from the core to the surface, where it is dissipated by convection and radiation. That is why the skin has a reddish appearance to it. Glands secrete sweat onto surface of the skin, which later evaporates. As water have a high latent heat of evaporation, meaning that extra energy is needed to aid the process of evaporation,
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