Which of the following is an example of negative feedback in the endocrine system?

a. when the amount of a hormone reaches a certain level, the endocrine system stops releasing that hormone.
b. when a hormone travels through the bloodstream, it will interact only with its target cells.
c. after age 40 or so, people’s muscle strength begins to decrease and their skin starts to wrinkle.
d. when people are startled by a frightening event, their hearts beat faster and their breathing increases.

A. When the amount of a hormone reaches a certain level, the endocrine system stops releasing that hormone.

The answer would be c (set)hope this ! (:

20 times a minute is usually the average respritory rate of an adult. additionally the patient is breathing on his own, is clearly maintaining his airway, and is intaking a sufficient amount of air. you shouldn't use a bag valve mask, cpap, or other form of positive pressure ventilation, unless the patient has lost control of his airway, and is not breathing (apneic) or has rapid breathing or slow and shallow respirations. this patient would most likely and should be put on an non-rebreather mask or nrb attached to 100% high flow oxygen at 15 l/min. don't use a nasal cannula, as the amount of oxygen it provides is limited with a rate of 6 l/min.