Category: 

What Is the Relationship Between Positive Feedback and Homeostasis?

Article Details
  • Written By: Alex Paul
  • Edited By: Angela B.
  • Last Modified Date: 18 September 2014
  • Copyright Protected:
    2003-2014
    Conjecture Corporation
  • Print this Article
Free Widgets for your Site/Blog
The seahorse is among the only animals on Earth which has males bear the young.  more...

September 30 ,  1949 :  The Berlin Air Lift ended.  more...

Homeostasis, which is the body’s ability to maintain physiological factors such as acid levels and blood sugar within safe ranges, is essential for a healthy body. Positive feedback and homeostasis occur in certain situations, such as during childbirth, when a runaway effect is required. The greater the measurement of a certain level in the body during positive feedback and homeostasis, the more it increases. Negative feedback, which is far more common in the body, involves the body acting to keep levels within a certain range.

The body has a number of systems and characteristics that need to be accurately controlled for it to function effectively. If, for example, the amount of blood sugar in a person’s body is too high, then there are systems to reduce the amount quickly and efficiently. When the body regulates itself to maintain a constant dynamic environment, it is known as homeostasis. Homeostasis is so important that almost all diseases can be attributed to a breakdown in homeostasis processes, or homeostatic imbalance.

There are two types of homeostasis — positive feedback and negative feedback. Positive feedback and homeostasis is far less common than negative feedback. When negative feedback occurs, the body senses that a certain level is too high or too low and acts so the level moves in the opposite direction. If, for example, the pH level that measures acidity is too high, then negative feedback will act to reduce the level of acid. Regulation of blood sugar levels is another example of negative feedback.

Ad

Positive feedback and homeostasis mean the body acts to accelerate or increase the level of an event that has already been started. While negative feedback usually acts to keep a physiological measurement within a certain safe range, positive feedback is only used when the body needs to move outside regular ranges. For example, if positive feedback were used for blood glucose levels, then the body would act as sugar levels increased to increase them further, which would have disastrous consequences. This means these processes are only useful in very specific cases in which a runaway effect is required.

An example of positive feedback and homeostasis is when a person has a cut or damage to a blood vessel. To stop bleeding, a positive feedback response is initiated in which platelets in the blood accumulate and clot around the wound. This relatively quickly stops the cut from bleeding. Another example is during childbirth, when chemicals are released to make contractions become stronger as labor continues.

Ad

More from Wisegeek

You might also Like

Discuss this Article

MrsPramm
Post 2

@Ana1234 - I always think of it in terms of what it can do for me psychologically. I think kinds of "good addiction" can go under this kind of feedback. So, if you exercise in a way that releases endorphins and makes you feel good, you're more likely to want to do it again and again. Then, the more you do, the more you'll want to do.

Of course, it only works to a certain point though, because most people don't end up exercising all day every day. But I guess that means that addiction to drugs probably works through a positive feedback loop as well. In that case you aren't able to stabilize it because the reaction to the drugs gets weaker, so you keep wanting to take more and more of them.

Ana1234
Post 1

I know that climate change is often associated with positive feedback mechanisms, but I'd never thought of the body that way. I guess it's just a general scientific term used for any reaction.

I suppose if there is a positive feedback happening in the body it requires something to stop it when it's served it's purpose. For example, the labor pains will have to stop after the baby is born, so there must be something that stopped the positive feedback mechanism that's causing that reaction to increase.

Post your comments

Post Anonymously

Login

username
password
forgot password?

Register

username
password
confirm
email