Watch this animation (http://openstaxcollege.org/l/ bloodflow1) to see how blood flows
Chapter 13, Problem 7(choose chapter or problem)
Watch this animation (http://openstaxcollege.org/l/ bloodflow1) to see how blood flows to the brain and passes through the circle of Willis before being distributed through the cerebrum. The circle of Willis is a specialized arrangement of arteries that ensure constant perfusion of the cerebrum even in the event of a blockage of one of the arteries in the circle. The animation shows the normal direction of flow through the circle of Willis to the middle cerebral artery. Where would the blood come from if there were a blockage just posterior to the middle cerebral artery on the left?
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