The pulse is created by which mechanism?

The pulse is created by which mechanism?

• A. Relaxation of ventricles
• B. The forceful pumping of blood out of the left ventricle into the major arteries
• C. Blood returning to the heart via veins
• D. The contraction of the left atrium

Answer: (B)

The pulse comes from the surge of blood that occurs when the heart contracts and ejects blood into the arterial system. When the left ventricle contracts (systole), it pushes a bolus of blood into the aorta and other major arteries. This rapid ejection raises arterial pressure and stretches the elastic walls of these vessels. As the pressure wave travels through the arteries, it is felt as the palpable pulse in peripheral arteries. The other actions—relaxation of the ventricles, venous return, or contraction of the left atrium—contribute to circulation in other ways but do not generate the main pressure wave that creates the pulse.

The pulse comes from the surge of blood that occurs when the heart contracts and ejects blood into the arterial system. When the left ventricle contracts (systole), it pushes a bolus of blood into the aorta and other major arteries. This rapid ejection raises arterial pressure and stretches the elastic walls of these vessels. As the pressure wave travels through the arteries, it is felt as the palpable pulse in peripheral arteries. The other actions—relaxation of the ventricles, venous return, or contraction of the left atrium—contribute to circulation in other ways but do not generate the main pressure wave that creates the pulse.