Solve the Following Proportion

question 140

Multiple Choice

Solve the following proportion.

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Definitions:

AV Node

The atrioventricular node is an element of the heart's conduction system that regulates heart rate by decelerating the electrical impulse prior to its transfer from the atria to the ventricles.

Action Potential

Change in membrane potential in an excitable tissue that acts as an electric signal and is propagated in an all-or-none fashion.

Atria Contract

refers to the phase in the cardiac cycle when the atria (upper chambers of the heart) contract to push blood into the ventricles.

Plateau Phase

Prolongation of the depolarization phase of a cardiac muscle cell membrane; results in a prolonged refractory period.