What are positive and negative feedback loops?

Positive and negative feedback loops are mechanisms that regulate biological processes in the body.

Positive feedback loops amplify or increase the output of a process. In other words, the output of the process leads to a further increase in the output. A classic example of a positive feedback loop is the process of childbirth. As the baby moves down the birth canal, pressure on the cervix increases, which stimulates the release of the hormone oxytocin. Oxytocin causes the uterus to contract, which further increases pressure on the cervix, leading to even more oxytocin release and stronger contractions.

Negative feedback loops, on the other hand, dampen or decrease the output of a process. In other words, the output of the process leads to a decrease in the output. A classic example of a negative feedback loop is the regulation of blood glucose levels. When blood glucose levels rise, the pancreas releases insulin, which causes cells to take up glucose from the blood. As glucose levels decrease, the pancreas stops releasing insulin, allowing glucose levels to stabilize.

Both positive and negative feedback loops are important in maintaining homeostasis, the body’s internal balance. However, excessive positive or negative feedback can lead to pathological conditions and disease.