As the Impulse from the SA Node Spreads Across the Atria

question 47

Multiple Choice

As the impulse from the SA node spreads across the atria, it is prevented from stimulating the ventricles

• A) SA node.
• B) AV node.
• C) tricuspid and bicuspid valves.
• D) semilunar valves.
• E) by the fibrous cardiac skeleton.

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Definitions:

Exchange

The process of trading or swapping substances or values, which in a biological context often refers to the transfer of gases or nutrients between cells and their environment.

Endothelium

Layer of flat cells lining blood and lymphatic vessels and the chambers of the heart.

Precapillary Sphincters

Circular muscular valves located at the entrance of capillaries, regulating blood flow into the capillary beds according to the body's needs.

Tunica Media

Middle, usually muscular, coat of an artery or another tubular structure.