The Sinoatrial Node Is the Heart's Normal Pacemaker Because

question 23

Multiple Choice

The sinoatrial node is the heart's normal pacemaker because

• A) it has the fastest natural rate of autorhythmicity.
• B) it has both sympathetic and parasympathetic innervation.
• C) it lies in the right atrium.
• D) activation of K+ channels occurs more rapidly in this region than elsewhere in the heart.
• E) none of these answers.

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Definitions:

Signal-detection Theory

A means to quantify the ability to discern between information-bearing patterns and random patterns that distract from the information.

Correct Rejection

In signal detection theory, the accurate identification that a signal is not present.

False Alarm

An erroneous alert or notification indicating the presence of a threat or condition that in reality does not exist.

Miss

To fail to hit, reach, catch, or otherwise make contact with something; also used to express a feeling of loss or absence.