Question

progressive enhancement of uterine contractions during labor are necessary for childbirth to occur. this progressive increase in contraction strength is due to which of the following? a.) stimulus b.) positive feedback loop c.) control center d.) negative feedback loop

Explanation:

• Stimulus: A stimulus is a change in the environment that can trigger a response. While stimuli are involved in various biological processes, it does not specifically explain the progressive increase in contraction strength during labor.
• Positive feedback loop: In a positive feedback loop, the response reinforces the stimulus, leading to an amplification of the effect. During labor, the stretching of the cervix (stimulus) triggers the release of oxytocin. Oxytocin then causes stronger uterine contractions, which further stretch the cervix, leading to more oxytocin release. This cycle of increasing contraction strength is a classic example of a positive feedback loop.
• Control center: The control center is a component of a feedback loop that receives information from sensors and initiates a response. While the control center (such as the brain or endocrine glands) is involved in regulating many physiological processes, it does not directly explain the mechanism of increasing contraction strength during labor.
• Negative feedback loop: In a negative feedback loop, the response counteracts the stimulus, leading to a stabilization of the system. This is the opposite of what happens during labor, where the response (uterine contractions) amplifies the stimulus (cervical stretching).

Answer:

B. Positive feedback loop