ANATOMY

Detailed explanation-1: -Positive feedback mechanisms are rare. It amplifies changes rather than reversing them. The release of oxytocin from the posterior pituitary gland during labor is an example of positive feedback mechanism. Oxytocin stimulates the muscle contractions that push the baby through the birth canal.

Detailed explanation-2: -Positive feedback loops enhance or amplify changes; this tends to move a system away from its equilibrium state and make it more unstable. Negative feedbacks tend to dampen or buffer changes; this tends to hold a system to some equilibrium state making it more stable.

Detailed explanation-3: -Oxytocin is one of the few hormones regulated by a positive feedback mechanism. In both childbirth and breastfeeding, oxytocin is released and causes additional release of oxytocin.

Detailed explanation-4: -Positive feedback occurs when a product feeds back to increase its own production. This causes conditions to become increasingly extreme. An example of positive feedback is milk production by a mother for her baby. As the baby suckles, nerve messages from the nipple cause the pituitary gland to secrete prolactin.

Detailed explanation-5: -Hormone production and release are primarily controlled by negative feedback. In negative feedback systems, a stimulus causes the release of a substance whose effects then inhibit further release. In this way, the concentration of hormones in blood is maintained within a narrow range.