Question

quick check: fill in the blank using word bank
another example of a positive feedback loop in the body is birth. when it is time for a baby to be born,
__________, in the mothers body stimulate the hypothalamus in her brain. the hypothalamus acts as
a__________, signaling cells in her pituitary to release the hormone oxytocin. oxytocin acts on the
muscles in her uterus, causing contractions. oxytocin also acts on the placenta to cause the release of
prostaglandins, which stimulate more uterine contractions. this process causes the hypothalamus to signal the
pituitary gland to release_________________ oxytocin, causing muscle contractions and prostaglandin
production to_________________. labor ends when the baby has been born and the placenta has been
expelled.

Explanation:

• Receptors: In the context of the body's feedback loop during birth, receptors in the mother's body detect the appropriate signals (like the baby being ready to be born) and stimulate the hypothalamus.
• Control center: The hypothalamus is known as a control center in the body's regulatory systems. It receives input (from receptors) and then signals other parts (like the pituitary gland) to take appropriate action (release oxytocin in this case).
• More: As the positive - feedback loop of labor progresses, the hypothalamus signals the pituitary gland to release more oxytocin. This is because in a positive - feedback loop, the response (uterine contractions) further stimulates the release of the hormone (oxytocin).
• Increase: The release of more oxytocin and prostaglandins (which are also stimulated by oxytocin) causes muscle contractions and prostaglandin production to increase. This intensifies the labor contractions until the baby and placenta are expelled.

Answer:

1. receptors
2. control center
3. more
4. increase