What is Homeostasis?
In the mid- nineteenth century, French physiologist Claude Bernard (1813-1878) showed that control of body temperature in warm- blooded animals resides in the nervous system. He also developed the concept of homeostasis as he demonstrated that animals could maintain constant body temperature and blood glucose concentration in spite of varying external conditions (Ochoa, 2007, page 38). Homeostasis provides cells within the body with a relatively constant environment, so the physiological processes can proceed at optimum rates, no matter what is going on outside the body. Due to this the body is constantly monitoring and adjusting body thermoregulation, osmoregulation, and blood glucose (Jones, 1997, page 323). It involves monitoring changes in the external and internal environment by means of receptors and adjusting the composition of the body fluids accordingly (Oxford, 2004).
A process which aims to keep a potentially fluctuating feature within narrow parameters uses negative feedback mechanisms. In any feedback system there must be a detector to measure the value of the feature to be controlled. The detector will measure if a value is higher or lower than that required and will then effect a change to bring the value back to its correct level. This is called the effector. The effector will continue making its changes until perhaps the level of the value might dip into the ‘too low’ parameter and then the effector will make other changes to accommodate that problem. The feedback is called ‘negative’ as it stops the effector from doing its usual job and stimulates it to do the opposite.
Specialised cells in humans are detectors, such as the brain and some organs such as the pancreas. Different organs act as effectors e.g. the skin in temperature regulation or the kidneys in water content. The information is passed from detectors to effectors via nerves or blood as chemicals called hormones (Jones, Mary and Geoff 1997).
Specialised cells in humans are detectors, such as the brain and some organs such as the pancreas. Different organs act as effectors e.g. the skin in temperature regulation or the kidneys in water content. The information is passed from detectors to effectors via nerves or blood as chemicals called hormones (Jones, Mary and Geoff 1997).