Final answer:
Stroke volume is the amount of blood pumped by the left ventricle of the heart with each beat, usually about 70-80 milliliters. It's a key component in calculating cardiac output as well as the ejection fraction, a percentage measure of blood volume ejected with each heartbeat.
Step-by-step explanation:
Stroke volume (SV) is defined as the quantity of blood that is pumped out of the left ventricle of the heart during each systolic cardiac contraction. Typically, this volume is in the range of 70–80 milliliters. Stroke volume, when multiplied by heart rate (HR), determines the cardiac output (CO), which is the total volume of blood the heart pumps per minute.
During the ventricular ejection phase of ventricular systole, the heart's contraction raises the pressure in the ventricle higher than in the aorta and pulmonary artery, causing blood to be pumped through the open pulmonary and aortic valves. The end systolic volume (ESV) is the volume of blood remaining in the ventricle after contraction, typically 50–60 mL. Stroke volume also plays a role in calculating ejection fraction, representing the percentage of blood ejected from the heart with each beat.