ANATOMY

Detailed explanation-1: -When you get cut, your skin cells release hormones that signal platelets to come and stop the bleeding. Platelets then release more hormones that signal even more platelets to help stop bleeding. The hormone signals continue until the cut is closed.

Detailed explanation-2: -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-3: -Baroreceptor exerts control of mean arterial pressure as a negative feedback loop. Nerve impulses from arterial baroreceptors are tonically active; increases in arterial blood pressure will result in an increased rate of impulse firing.

Detailed explanation-4: -Answer and Explanation: The correct answer: The one option that is true for positive feedback systems is a. They operate in such a way that the initial stimulus is enhanced and increased.