The arcuate arteries are small curved branches of arteries supplying the |brain| with fresh ~blood~. ~Blood~ supply to the |brain|, about 250 milliliters every second, is constant. The |brain| is more sensitive to lack of oxygen than any other organs in the body. |Brain| cells suffer permanent damage if their ~blood~ supply stops for more than two minutes. For this reason, the body has developed a safety system, called autoregulation, by which various ~nerves~ act to maintain the flow of ~blood~ to the |brain| even if the flow to the rest of the body falls dramatically, as in the case of a severe hemorrhage.
