Which Statement Best Describes Why Atrial Depolarization Is Usually Not

question 118

Multiple Choice

Which statement best describes why atrial depolarization is usually not detected on a normal ECG?

• A) It occurs at the same time as the QRS complex.
• B) The electrodes cannot be placed high enough on the chest to detect the atria.
• C) The voltage change in the atria is minimal and therefore does not register on an ECG.
• D) The atria are so small and the depolarization happens so quickly that it cannot be detected.
• E) The atria do not contract only the AV valves open.

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Definitions:

Mask Instruction

A mask instruction in computing or programmable logic controllers (PLCs) is used to selectively enable or disable bits in a word or byte by applying a mask pattern.

Input Scan

One of three parts of the PLC scan. During the input scan, input terminals are read and the input table is updated accordingly.

Stop Button

A control mechanism used to immediately halt operations or processes in a system or machinery.

PLC System

A system used in industrial automation to control machinery and processes, consisting of programmable logic controllers.