Q.42 A healthy individual has the cardiac output of 5.5 L and heart rate of 72 beats per minute.
The stroke volume of the individual is _________ mL.
The stroke volume for this healthy individual is approximately 76 mL. This value is calculated using the standard physiological formula for cardiac output.
Calculation Method
Cardiac output (CO) equals stroke volume (SV) multiplied by heart rate (HR), so SV = CO / HR. Here, CO measures 5.5 L (or 5500 mL) per minute, and HR is 72 beats per minute. Dividing 5500 mL by 72 yields 76.39 mL, typically rounded to 76 mL in such problems [code_execution].
Physiological Context
Stroke volume represents blood ejected per heartbeat from the left ventricle, normally ranging 50-100 mL in healthy adults at rest. Values around 70-80 mL align with typical resting conditions for cardiac output near 5-6 L/min. This individual’s parameters fall within normal limits, reflecting efficient heart function.
Introduction to Stroke Volume Cardiac Output 5.5 L Heart Rate 72
Stroke volume cardiac output 5.5 L heart rate 72 beats per minute is a classic calculation in cardiovascular physiology, vital for CSIR NET life sciences aspirants. This query tests understanding of how the heart pumps blood efficiently at rest. The stroke volume emerges as 76 mL, showcasing normal heart function.
Step-by-Step Stroke Volume Formula
The core equation is CO = SV × HR, rearranged to SV = CO / HR. Convert 5.5 L to 5500 mL, then divide by 72: 5500 ÷ 72 = 76.39 mL (rounded to 76 mL) [code_execution]. No options are listed, but common MCQ choices might include 70 mL (underestimate), 80 mL (close), or errors like 396 mL (unrealistic without unit conversion).
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Option Analysis (Typical MCQs): If options were 70 mL, 76 mL, 80 mL, 100 mL: 70 mL assumes standard 5 L CO (too low here); 76 mL matches exact math; 80 mL overestimates slightly; 100 mL ignores precise division.
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Heart rate stays constant at 72 bpm, a resting norm.
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Ensures unit consistency: L/min to mL/beat.
Clinical Significance
Stroke volume cardiac output 5.5 L heart rate 72 indicates healthy ejection, influenced by preload, contractility, and afterload. In exams like CSIR NET, such problems link to Frank-Starling law and exercise adaptations. Abnormal values signal issues like heart failure.
