As you are walking home from studying at the library late one evening, you get startled by a strange sound behind you. This activates your sympathetic nervous system. What affect does this change have on stroke volume

It has a positive change in stroke volume.

Explanation:

The amount of blood pumped out of the left ventricle of the heart during each systolic cardiac contraction is referred to as stroke volume. During systolic contraction, the heart pumps blood into circulation.

Sympathetic nerves also innervate or stimulate the middle muscular layer of the heart wall. Therefore, an increase of activity in the sympathetic nervous system will trigger an increase in the force of contraction of the heart and, therefore, increase stroke volume. An increase in stroke volume also translates to the pressure of blood being pumped through the arteries.

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