Standing still and at attention for long periods can result in inadequate venous return. The effects of this can be seen when even young and healthy soldiers sometimes faint when standing at attention for long periods. Which of the following is NOT occurring to promote return of blood from the venous system in this situation?

A. one way flow in the venous system due to valves
B. sympathetic activation of smooth muscle in large veins
C. skeletal muscle activity compressing veins and forcing blood flow
D. ventricular contraction


Answer: C

Biology & Microbiology

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What will be an ideal response?

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