NEET Biology: cardiac output Practice Questions
14 free multiple-choice questions on cardiac output (Human Physiology) for NEET Biology, each with the correct answer and a step-by-step explanation. Attempt a question, then reveal the solution to check your reasoning.
Practice thousands more NEET questions in the app →Q1. If the heart rate of a person increases while the stroke volume remains constant, what happens to the overall cardiac output?
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Correct answer: C — Cardiac output increases
Since Cardiac Output (CO) = Heart Rate (HR) × Stroke Volume (SV), if HR increases and SV is constant, the total Cardiac Output will increase proportionally.
Q2. The cardiac output (CO) of the human body is fundamentally determined by which two main physiological parameters?
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Correct answer: B — Heart Rate and Stroke Volume
Cardiac Output (CO) is calculated as the product of Heart Rate (HR) and Stroke Volume (SV). Therefore, these two parameters are the fundamental determinants of CO.
Q3. If the heart rate remains constant, an increase in Stroke Volume (SV) will lead to an increase in Cardiac Output (CO). This statement is based on the fundamental relationship where CO is directly proportional to which factor?
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Correct answer: C — Heart Rate
Since CO = SV × HR, if HR is constant, an increase in SV directly results in an increase in CO.
Q4. Which of the following is NOT considered a direct component used in calculating the Cardiac Output?
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Correct answer: B — Peripheral Resistance
Cardiac Output is calculated using Heart Rate and Stroke Volume. Peripheral Resistance and Blood flow rate are related to systemic circulation but are not direct components of the CO calculation formula.
Q5. Cardiac output (CO) is fundamentally calculated by which of the following formulas?
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Correct answer: D — Stroke Volume × Heart Rate
Cardiac Output (CO) is the volume of blood pumped by the heart per minute. It is calculated by multiplying the Heart Rate (beats per minute) by the Stroke Volume (volume pumped per beat).
Q6. Which component of Cardiac Output represents the volume of blood contained in the ventricles just before contraction (the stretch on the muscle)?
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Correct answer: C — Preload
Preload is the degree of stretch on the ventricular muscle fibers at the end of diastole (filling phase) and directly influences Stroke Volume.
Q7. The Cardiac Output (CO) is mathematically determined by the product of which two primary physiological parameters?
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Correct answer: A — Heart Rate and Stroke Volume
Cardiac Output (CO) is calculated as Heart Rate (HR) multiplied by Stroke Volume (SV).
Q8. A patient experiencing severe anemia (low hemoglobin) will likely have a reduced oxygen-carrying capacity of the blood. How does this generally impact the overall Cardiac Output (CO) required for the body to maintain adequate oxygen delivery?
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Correct answer: B — CO will decrease
To compensate for reduced oxygen carrying capacity (due to anemia), the body often attempts to maintain adequate oxygen delivery by increasing the Cardiac Output (CO), usually by increasing heart rate and/or stroke volume.
Q9. Which factor most directly influences the amount of blood pumped out by the heart with each beat (Stroke Volume)?
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Correct answer: C — Preload
Stroke Volume is highly dependent on the ventricular filling (Preload) and the resistance the blood must overcome to exit the ventricle (Afterload).
Q10. If a patient's heart rate remains constant, but the stroke volume (SV) significantly increases, what happens to the Cardiac Output (CO)?
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Correct answer: A — CO increases
Since CO = HR × SV, if HR is constant and SV increases, the Cardiac Output must increase proportionally.
Q11. Cardiac Output (CO) is the volume of blood pumped by the heart per minute. Which of the following factors directly influences the regulation of Cardiac Output?
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Correct answer: C — Stroke Volume
Cardiac Output (CO) is mathematically calculated as Heart Rate (HR) multiplied by Stroke Volume (SV). While all listed factors are related to cardiovascular function, Stroke Volume (the volume pumped per beat) is a primary determinant of the output volume, along with Heart Rate.
Q12. During strenuous physical exercise, the body increases Cardiac Output primarily to meet the heightened metabolic demands of the active muscles. This increase is achieved by increasing which component of the CO equation?
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Correct answer: D — Increasing both Heart Rate and Stroke Volume
During exercise, CO increases significantly, usually by increasing both Heart Rate (HR) and Stroke Volume (SV) to deliver more oxygenated blood to the working tissues.
Q13. If a patient experiences an increase in venous return (preload) while maintaining a constant heart rate, how is the cardiac output likely to be affected, assuming stroke volume remains unchanged?
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Correct answer: B — It will increase
Cardiac Output (CO) is directly dependent on Stroke Volume (SV). According to the Frank-Starling mechanism, increased venous return (preload) stretches the ventricular muscle fibers, leading to an increased volume of blood filling the ventricle, thus increasing the Stroke Volume (SV). If SV increases while HR is constant, CO will increase.
Q14. In a healthy adult at rest, the typical resting Cardiac Output is approximately how many liters per minute?
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Correct answer: C — 4.0 L/min
The typical resting Cardiac Output for an adult is around 5 L/min to 6 L/min, and 4.0 L/min is the closest standard option reflecting a healthy resting state.
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