Negative and Positive Feedback Loops

Feedback loops are important in allowing living organisms to maintain homeostasis. Items such as Ph, fluids, and temperature need to be kept in balance and feedback loops help. There are negative and positive feedback loops,

With a negative feedback loop you move above or below a set target. An example found at your house is your thermostat. If it is set at 70 degrees fahrenheit,and the temperature  gets above this the air conditioner will turn on in order to cool the house, and when it falls below 70 degrees it will turn off. It will continue to repeat this process. 

An example in the human body is if your glucose levels get to high then insulin will be released to lower it and if your glucose levels get to low then glucagon is released which will raise glucose levels.

negative feedback loop

With A positive feedback loop or amplification you move away from a target set point.  For example, if the speed limit is 55 mph a positive feedback would see this speed limit as a challenge and would try to go much faster than the limit of 55 mph. It would amplify the speed.

During childbirth contractions are triggered by pressure from the head of the baby on the cervix, the contractions increase the pressure on the cervix which causes more contractions, which in turn causes more pressure and more contractions. The contractions are amplified with this positive feedback.

So in summary, feedback loops help organisms maintain homeostasis. Homeostasis is the process by which an organism maintains a stable internal environment despite changes in the external environment. This in turn keeps the internal environment in balance and keeps the organism alive.