Home › DHA Medical Licensing Exam › Physiology › Cardiac Cycle and Output › What closes the tricuspid and mitral valves earl…
What closes the tricuspid and mitral valves early in ventricular systole?
ABlood pushing back to the atria
BPapillary muscles pulling hard
CThe semilunar valves opening
DAtrial systole restarting
Answer & Solution
Correct answer: A. Blood pushing back to the atria
1. As the ventricle contracts its pressure quickly exceeds that of the relaxed atria.
2. This causes blood to flow back toward the atria, which closes the tricuspid and mitral valves.
3. The semilunar valves are still shut at this stage, so no blood leaves yet.
_Source: OpenStax Anatomy and Physiology (CC BY 4.0), Ch 19 "The Cardiovascular System: The Heart", section 19.3 | Cardiac Cycle_
Related questions
What is the mean stroke volume for a resting 70 kg individual?Roughly how long does atrial systole last?Why does the left ventricle generate a higher pressure than the right during ejection?What produces the dicrotic notch seen on a blood pressure tracing?Roughly how long does ventricular diastole last?Roughly how long does ventricular systole last in total?Which principle links ventricular stretch to the force of contraction?How is stroke volume calculated from echocardiogram measurements?