What is an example of a homeostatic feedback mechanism?

Answer 1

There are numerous examples of homeostatic mechanisms. One of the best examples is found in warm blooded animals, which have a system to maintain their internal temperature. Essentially, they sweat to release heat, and constrict their blood vessels to preserve heat.

Answer 2

When a change of variable occurs, there are two main types of feedback to which the system reacts:

Negative feedback is a reaction in which the system responds in such a way as to reverse the direction of change. Since this tends to keep things constant, it allows the maintenance of homeostasis. For instance, when the concentration of carbon dioxide in the human body increases, the lungs are signaled to increase their activity and expel more carbon dioxide. Thermoregulation is another example of negative feedback. When body temperature rises (or falls), receptors in the skin and the hypothalamus sense a change, triggering a command from the brain. This command, in turn, effects the correct response, in this case a decrease in body temperature.

*In positive feedback, the response is to amplify the change in the variable. This has a destabilizing effect, so does not result in homeostasis. Positive feedback is less common in naturally occurring systems than negative feedback, but it has its applications. For example, in nerves, a threshold electric potential triggers the generation of a much larger action potential. Two exceptions, (See also leverage points.) Blood clotting and events in childbirth are other types of positive feedback.

Sustainable systems require combinations of both kinds of feedback. Generally with the recognition of divergence from the homeostatic condition positive feedbacks are called into play, whereas once the homeostatic condition is approached, negative feedback is used for "fine tuning" responses. This creates a situation of "metastability", in which homeostatic conditions are maintained within fixed limits, but once these limits are exceeded, the system can shift wildly to a wholly new (and possibly less desirable) situation of homeostasis. Such catastrophic shifts may occur with increasing nutrient load in clear rivers suddenly producing a homeostatic condition of high eutrophication and turbidity, for instance.

Answer 3

Homeostatis is the maintenance of constant conditions in the internal environment of the body despite large swings in the external environment. For example, when the external temperature drops, the body's mechanisms create body heat in an attempt to keep the internal temperature within a suitable range.

Answer 4

Shivering that occurs as body temperature drops. ( Anatomy & Phys)