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Unit 4

4.5 Feedback

2 min readโ€ขmay 30, 2020

Annika Tekumulla


Homeostasis

Based upon the environment around the organism, the timing, and coordination, there can be either a positive or negative feedback. Organisms use feedback to maintain homeostasis as well as respond to the environment.ย 

โŽย Negative Feedback Loops

Negative feedback loops are the response of reactions and leads to a decrease in those reactions. Negative loops also maintain homeostasis by creating optimal internal environments. Negative loops are also able to return a system back to target homeostasis.

An example of negative feedback loops is blood sugar regulation. When you eat food, blood glucose levels rise. This causes a response by the pancreas to release insulin, which then causes the blood glucose levels to decrease making it a negative feedback loop.

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Image courtesy of Lumen Learning.

Diabetes would disrupt the negative feedback loop of blood sugar regulation. Diabetes is a condition that can be caused by an imbalance of insulin. There can be either too little insulin or a resistance to insulin. When there is a problem in the negative feedback loop, it can lead to high blood glucose levels that can lead to adverse health effects.ย 

โœ… Positive Feedback Loops

Positive feedback loops are used to increase the change in the cell by amplifying or speeding up the process. Positive feedback loops can also be called โ€œsnowballingโ€ effects. It is also important to remember that without a stop or counterbalance, the positive feedback loop can not be controlled.

An example of a positive feedback loop is childbirth. During labor, a chemical called oxytocin is released. Labor is a positive feedback loop because oxytocin causes a response for contractions to intensify and occur quicker. After the birth, the loop is interrupted, stretching and contractions end, and the loop is finished.

https://firebasestorage.googleapis.com/v0/b/fiveable-92889.appspot.com/o/images%2F106_Pregnancy-Positive_Feedback.jpg?alt=media&token=eb96eec7-5c62-451e-a4cd-fdf0da3514ac

Image courtesy of BCcampus.

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