In the Cardiac Cycle,which Statement Is True

question 212

Multiple Choice

In the cardiac cycle,which statement is true?

• A)All blood is actively pumped from the ventricles.
• B)Most blood is actively pumped from the atria.
• C)All blood is actively pumped into the ventricles.
• D)Most blood is actively pumped into the atria.

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Definitions:

Precapillary Sphincter

A band of smooth muscle that regulates blood flow into the capillaries, largely controlling the microcirculation.

Action Potentials

Electrical impulses that travel along the membrane of a nerve or muscle fiber, initiating activity or movement.

Coronary Sinus

Short trunk that receives most of the veins of the heart and empties into the right atrium.

Cardiac Veins

Blood vessels that return deoxygenated blood from the myocardium (heart muscle) to the right atrium.