Final answer:
Stroke volume is the quantity of blood pumped by each ventricle per heart beat (option 4) , normally between 70-80 mL, with about 50-60 mL remaining as end systolic volume after ventricular contraction. Both ventricles pump the same amount of blood despite different pressures, which is critical for calculating cardiac output.
Step-by-step explanation:
The stroke volume is defined as the amount of blood pumped by each ventricle of the heart per beat. During the ventricular ejection phase of ventricular systole, the ventricles contract, raising the internal pressure and forcing blood out through the semilunar valves into the pulmonary trunk and aorta. The stroke volume normally ranges between 70-80 mL, and after the contraction, there is an end systolic volume (ESV) of 50-60 mL of blood remaining in the ventricles.
The left ventricle generates a higher pressure due to the higher resistance in the systemic circulation compared to the pulmonary circulation, yet both ventricles pump the equivalent volume of blood. These cardiac dynamics are essential for maintaining proper cardiac output, which is the volume of blood each ventricle pumps out of the heart in one minute, calculated by stroke volume multiplied by the heart rate.