ECG Online Electrocardiogram 3

Question 1

The QRS complex on an ECG primarily represents:

Accepted Answer

Ventricular depolarization

Answer

The QRS complex reflects depolarization of the ventricles.

Question 2

Which electrode color is standard for the right arm in the AHA labeling system?

Accepted Answer

White

Answer

Under AHA labeling, the right arm electrode is white.

Question 3

The natural pacemaker of the heart is the:

Accepted Answer

SA node

Answer

The sinoatrial (SA) node initiates each normal heartbeat.

Question 4

Muscle tremor (somatic) artifact appears on an ECG as:

Accepted Answer

Irregular, jagged, rapid spikes

Answer

Muscle tremor produces irregular, jagged spikes across the baseline.

Question 5

How many seconds does one large box on standard ECG paper represent?

Accepted Answer

0.20 sec

Answer

One large box equals 0.20 seconds at 25 mm/sec.

ECG (Electrocardiogram) Practice Test