Question

activity 1/2
ers: feedback loops
multiple - choice question
why is birthing a baby an example of positive feedback?
the contractions reduce the pressure on the cervix and reduce the amount of
hormones.
pressure from the baby releases hormones which stop the baby from being
born.
pressure from the baby releases hormones that causes contractions, which
intensify the pressure and cause more contractions.

Explanation:

In a positive feedback loop, a change leads to an amplification of that change. During childbirth, pressure from the baby on the cervix releases hormones (like oxytocin). These hormones cause contractions. The contractions then intensify the pressure on the cervix (due to the baby moving down further as the uterus contracts), which in turn causes more hormone release and more contractions. This cycle of increasing contractions (amplification of the initial change - pressure on the cervix) is characteristic of a positive feedback loop. The first option is incorrect as it describes a reduction (which would be negative feedback if it were maintaining a set - point, but even then the description of reduction in pressure and hormones is not in line with childbirth). The second option is wrong because the hormones do not stop the baby from being born; they facilitate the birth process.

Answer:

Pressure from the baby releases hormones that causes contractions, which intensify the pressure and cause more contractions.