Check your understanding: What type of feedback, positive or negative, is illustrated below? How do you know? Explain your thinking.
Uterine stretch Brain sends Oxytocin causes More and stronger
receptors are > Signals to release > the Uterine > Contractions until
activated Oxytocin Muscles to contract Birth
The feedback illustrated above is positive feedback. I can determine this because the series of events shown in the illustration results in an amplification or increase in the initial stimulus, which is the contractions of the uterine muscles. The activation of uterine stretch receptors signals the brain to release oxytocin, which then causes the uterine muscles to contract. These contractions lead to even more and stronger contractions until birth, indicating a positive feedback loop.
The feedback illustrated above is positive feedback. This can be determined by the following reasons:
1. The initial stimulus (uterine stretch) triggers a chain of events that amplifies the response.
2. The signal sent from the brain to release oxytocin further enhances the uterine contractions.
3. The increased contractions caused by oxytocin lead to even stronger contractions.
4. This cycle continues until birth occurs, further reinforcing the positive feedback loop.
In positive feedback, the response reinforces and increases the stimulus, resulting in a self-amplifying chain of events.
Based on the information provided, the feedback illustrated is positive feedback.
Positive feedback occurs when a system responds to a change or stimulus by amplifying or reinforcing that change.
In this case, the process described is the contraction of the uterine muscles during childbirth. The activation of uterine stretch receptors sends signals to the brain, which then releases oxytocin. Oxytocin causes the uterine muscles to contract. As a result, these contractions become more frequent and stronger until birth occurs.
The key to identifying this as positive feedback lies in the fact that the initial stimulus (activation of uterine stretch receptors) leads to an amplification or increase in the response (more and stronger contractions). The process continues in a self-reinforcing loop until the desired outcome is achieved (i.e., the birth of the baby). This is characteristic of positive feedback systems.