In an effort to bring mean arterial pressure back to normal after a hemorrhage, total peripheral resistance because the blood flow to most organs however, blood flow to the and is maintained because these organs are not greatly influenced by the baroreceptor reflex.

In an effort to bring mean arterial pressure back to normal after a hemorrhage, total peripheral resistance increases because the blood flow to most organs decreases. However, blood flow to the brain and heart is maintained because these organs are not greatly influenced by the baroreceptor reflex. 
Baroreceptor reflex is one of the body's homeostatic mechanisms that helps to maintain blood pressure at nearly constant levels. They are mechanoreceptors located in the carotid sinus and in the aortic arch. They function to sense pressure changes by responding to change in the tension of the arterial wall. 

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