Answer:
An example of a positive feedback loop in the body is the delivery of a baby.
Explanation:
Positive feedback implies the response that an organism provides when there is an alteration or change, promoting such change and not necessarily in relation to homeostasis.
Delivery of a baby is an example of positive feedback in humans. During childbirth, contractions of the maternal uterus cause the fetus to descend and its head to exert pressure on the cervix. The stimulation of the cervical nerves produces:
- An afferent signal that reaches the brain
.
- The brain, control center, sends a signal to the pituitary gland to release oxytocin.
- Oxytocin reaches the uterus and increases uterine contractions, thereby promoting the output of the fetus from the uterus.
Another example of positive feedback is blood clotting.
For the other options:
<em>Restoring oxygen levels to muscles after exercise, restoring body temperature or thermoregulation and increased excretion of urine due to increased fluid volume are mechanisms to recover homeostasis and are more related to negative feedback, for example, the inhibition of antidiuretic hormone promotes urine excretion.</em>
