MCAT Question A Day - 8/6/14 - Answer!
Cardiac output, which is the product of the heart rate and the stroke volume (the amount of blood pumped per contraction by either the left or the right ventricle) would most likely be:
A. greater if measured using the stroke volume of the left ventricle.
B. greater if measured using the stroke volume of the right ventricle.
C. the same regardless of which stroke volume is used.
D. dependent on the viscosity of the blood.
C is correct. Stroke volume must be the same for both ventricles. If it weren't, we'd have a never-ending backlog of blood in one or the other circulations, ending with the faster circulation running dry. To keep the whole system running smoothly, both halves of the circulation must pump the same quantity of blood with each stroke.
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C is correct. Stroke volume must be the same for both ventricles. If it weren't, we'd have a never-ending backlog of blood in one or the other circulations, ending with the faster circulation running dry. To keep the whole system running smoothly, both halves of the circulation must pump the same quantity of blood with each stroke.
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