Which statement best defines stroke volume?

Which statement best defines stroke volume?

• A. The amount of blood ejected by the ventricle in one contraction
• B. The amount of blood remaining after systole
• C. The volume of blood in the ventricle at end diastole
• D. The total blood pumped per minute

Answer: (A)

Stroke volume is the amount of blood ejected from a ventricle with a single heartbeat. After the ventricle fills during diastole, a contraction pushes out a portion of that blood into the aorta or pulmonary artery, and the quantity that leaves is the stroke volume. The other terms describe related but distinct quantities: end-diastolic volume is the blood in the ventricle at the end of diastole, end-systolic volume is what remains after contraction, and cardiac output is the total blood pumped per minute (stroke volume multiplied by heart rate). Thus, the best definition is the amount of blood ejected by the ventricle in one contraction.

Stroke volume is the amount of blood ejected from a ventricle with a single heartbeat. After the ventricle fills during diastole, a contraction pushes out a portion of that blood into the aorta or pulmonary artery, and the quantity that leaves is the stroke volume. The other terms describe related but distinct quantities: end-diastolic volume is the blood in the ventricle at the end of diastole, end-systolic volume is what remains after contraction, and cardiac output is the total blood pumped per minute (stroke volume multiplied by heart rate). Thus, the best definition is the amount of blood ejected by the ventricle in one contraction.