Define a cardiac cycle and the cardiac output.
Cardiac Cycle: The cardiac cycle refers to the sequential events in the heart which are cyclically repeated. It consists of systole and diastole of both the atria and ventricles. A healthy person shows 72 such cycles per minute, and the duration of a cardiac cycle is 0.8 seconds.
Cardiac Output: The cardiac output is defined as the volume of blood pumped out by each ventricle per minute. It is calculated by multiplying the stroke volume (approximately 70 mL of blood pumped out by each ventricle during a cardiac cycle) by the heart rate. The cardiac output averages 5000 mL or 5 litres in a healthy individual.
Explanation
The answer directly defines both terms using the textbook context. The cardiac cycle is explained as the repeating sequence of systole and diastole in atria and ventricles, with quantitative details (72 cycles/min, 0.8 seconds duration). Cardiac output is defined as blood volume pumped per ventricle per minute, derived from stroke volume × heart rate, with the average value of 5 litres. Both definitions are complete and exam-ready.