The volume in the pump when the pump piston is all the way down represents the _______.

The volume in the pump when the pump piston is all the way down represents the _______.

• A. End diastolic volume
• B. Stroke volume
• C. End systolic volume
• D. Residual volume

Answer: (C)

End systolic volume is the volume left in the ventricle after it has finished contracting and ejected blood. In the pump model, the piston at the bottom represents the chamber in a contracted state with the smallest volume, which corresponds to the volume remaining after systole. That remaining volume is exactly the end-systolic volume. End diastolic volume would be the largest volume just before contraction, when the ventricle is filled. Stroke volume is the amount ejected during systole, equal to end diastolic minus end systolic volumes. Residual volume isn’t the standard term used to describe this state in the ventricle.

End systolic volume is the volume left in the ventricle after it has finished contracting and ejected blood. In the pump model, the piston at the bottom represents the chamber in a contracted state with the smallest volume, which corresponds to the volume remaining after systole. That remaining volume is exactly the end-systolic volume.

End diastolic volume would be the largest volume just before contraction, when the ventricle is filled. Stroke volume is the amount ejected during systole, equal to end diastolic minus end systolic volumes. Residual volume isn’t the standard term used to describe this state in the ventricle.