Which of these statements correctly applies to the cardiac muscle?
A)It extracts oxygen and nutrients from the blood within its chambers.
B)It receives its blood supply primarily during ventricular systole when blood is forced into the vessels supplying the heart.
C) It receives its blood supply as the blood returning to the heart from the lung passes through the cardiac circulation before being pumped to the systemic circulation.
D) It receives most of its blood supply during ventricular diastole by means of the coronary circulation.

Question

Quizplus · Accepted Answer

The cardiac muscle receives most of its blood supply during ventricular diastole by means of the coronary circulation. During systole, the myocardium contracts and compresses the coronary blood vessels, reducing blood flow. However, during diastole, the vessels dilate and blood flow to the cardiac muscle increases.

Which of These Statements Correctly Applies to the Cardiac Muscle