On a Normal ECG, a Wave for Repolarization of the Atria

question 206

Multiple Choice

On a normal ECG, a wave for repolarization of the atria is not recorded.Why?

• A)The leads are not placed in a position to pick it up.
• B)No repolarization of the atria occurs normally.
• C)It occurs simultaneously with ventricular depolarization and is masked by the QRS complex.
• D)It does not travel through body fluids.
• E)It is too small to be picked up by external recording electrodes.

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Definitions:

Secondary Receptors

Protein molecules located on cell surfaces or within cells that bind to external signaling molecules after they have interacted with primary receptors, often amplifying the cellular response.

Chemoreceptors

Sensory receptors that respond to chemical stimuli, such as taste, smell, or changes in the blood's chemical composition.

Brainstem

The lower extension of the brain, connecting the cerebrum with the spinal cord, and controlling vital functions such as breathing and heart rate.

Cranial Nerves

Twelve pairs of nerves that are connected directly to the brain or brainstem and are responsible for motor and sensory functions of the head and neck.