Free medical quiz
The Cardiac Cycle Quiz
Focused SBA-style practice, followed by the answer and explanation for every question.
- Free now
- 5 questions
- Full bank
- 21 questions
- Answers
- Explained
Free question
Try one with the answer
A question from this quiz. Answer it to see the explanation students get.
Which statement best defines stroke volume in cardiac physiology?
- A The proportion of ventricular blood volume ejected during systole You picked ✕
- B The volume of blood ejected by one ventricle during a single cardiac cycle You picked ✓
- C The volume of blood pumped by the heart per minute You picked ✕
- D The amount of blood remaining in the ventricle after systole You picked ✕
- E The volume within one ventricle at the end of diastole You picked ✕
Correct!
Incorrect
The answer is B: The volume of blood ejected by one ventricle during a single cardiac cycle
Explanation
Why B is correct
See Systole and Diastole. Option B is correct. During diastole the ventricle fills with blood, and the volume it holds at the end of filling is the end-diastolic volume (EDV). During systole the ventricle contracts and ejects part of this blood into the aorta or the pulmonary trunk, but it does not empty completely. The volume left behind is the end-systolic volume (ESV). The stroke volume (SV) is the volume of blood ejected by one ventricle in one cardiac cycle, which is the difference between the two: SV = EDV minus ESV. At rest an average adult has a stroke volume of about 70 mL, and the normal range is roughly 55 to 100 mL. Stroke volume is one of the two determinants of cardiac output, the volume pumped per minute, which equals heart rate multiplied by stroke volume. The ejection fraction is the stroke volume expressed as a proportion of the end-diastolic volume. A good way to keep these terms apart is to remember that stroke volume is what leaves with each beat.
- Definition: Stroke volume is the volume of blood ejected by one ventricle in one cardiac cycle.
- Calculation: Stroke volume equals end-diastolic volume minus end-systolic volume.
- Normal value: About 70 mL at rest, with a range of roughly 55 to 100 mL.
- Cardiac output: Heart rate multiplied by stroke volume.
Why the other options are incorrect
- A. The proportion of ventricular blood volume ejected during systole: The fraction of the ventricular blood volume ejected during systole is the ejection fraction, which is expressed as a percentage. It describes the efficiency of the ventricle, not the volume ejected. Your answer
- C. The volume of blood pumped by the heart per minute: The volume of blood pumped by the heart each minute is the cardiac output. It is the stroke volume multiplied by the heart rate. This option combines stroke volume with heart rate. Your answer
- D. The amount of blood remaining in the ventricle after systole: The blood left in the ventricle after systole is the end-systolic volume. It stays behind and is not ejected. Stroke volume is the difference between the volume before contraction and the volume left behind. Your answer
- E. The volume within one ventricle at the end of diastole: The volume in the ventricle at the end of diastole is the end-diastolic volume, which is the amount of blood present before contraction. It is not the volume ejected. It is one of the two values needed to calculate stroke volume. Your answer
With Premium, questions you miss become Revision Coach flashcards, scheduled for review.
Question preview
What you will practise
More questions from this set. Start the quiz to answer them and see each explanation.
-
1
In the cardiac cycle, which event is directly responsible for the first heart sound (S1) heard on auscultation?
-
2
During a normal cardiac cycle at rest, which statement best describes the contribution of atrial contraction to ventricular filling?
Revise before you test
Review SimpleMed's doctor-written article, then return here to check recall.
Read the topic articleNeed wider coverage?
Explore every Cardiovascular System topic set, or build a tailored mixed session.
Browse subject quizzes