The Cardiac Electrical Impulse Normally Begins Spontaneously in the SA

question 7

Multiple Choice

The cardiac electrical impulse normally begins spontaneously in the SA node because

• A) of the superior location of the SA node in the right atrium.
• B) the SA node is the only area of the heart capable of spontaneous depolarization.
• C) of the rich sympathetic innervation of the SA node.
• D) this area produces action potentials more rapidly than any other portion of the conduction system.
• E) of action potentials from the cardioregulatory center.

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Definitions:

Basilic

Often related to the basilic vein, which is a large vein on the upper arm that helps drain parts of the hand and forearm.

Vertebral Artery

The vertebral artery is one of the major arteries of the neck that supplies blood to the brain, particularly the posterior portion, including the cerebellum and the brainstem.

Posterior Cerebral Artery

A blood vessel that supplies blood to the occipital lobe of the brain, important for vision.

Innominate Artery

Another term for the brachiocephalic artery, which is a major blood vessel that supplies blood to the right arm and the right side of the head and neck.