Question

When is a positive feedback system useful in the body and provide one example?

1) During blood clotting to amplify the clotting process
2) During childbirth to increase the intensity of contractions
3) During digestion to enhance the release of digestive enzymes
4)uring breathing to increase the rate of respiration

Answer 1

Positive feedback loops in the body are designed to rapidly intensify a response until a definitive endpoint is reached, such as 2) during childbirth with the increased production of oxytocin leading to stronger contractions, or during the blood clotting process to quickly halt bleeding.

Step-by-step explanation:

Positive feedback systems are useful in the body when a rapid completion of a process is critical and when there is a definite end point. A classic example of a positive feedback loop in action is during childbirth, where the release of the hormone oxytocin leads to increased intensity of uterine contractions. This results in pain that is sensed by the nervous system, which instead of dampening the contractions, leads to the production of more oxytocin. This cycle continues until the baby is born, which is the definite end point in this physiological process.

Another occurrence of positive feedback can be seen during the process of blood clotting. As a clotting factor is activated in response to a bleed, it triggers the activation of the next factor in the cascade, amplifying the clotting response until a stable fibrin clot is formed. This feedback loop ensures that bleeding is rapidly controlled and only occurs when necessary, like childbirth, to solve a critical event.