and ANSWERS>s (Basic A Dysrhythmia) | Verified &
Updated
Section 1: Basic Cardiac Anatomy & Electrophysiology
1. What is the normal intrinsic rate of the Sinoatrial (SA) node?
A) 40-60 beats per minute
B) 60-100 beats per minute
C) 100-150 beats per minute
D) 20-40 beats per minute
Answer: B
2. Which of the following structures is known as the heart's primary
pacemaker?
A) Atrioventricular (AV) node
B) Bundle of His
C) Sinoatrial (SA) node
D) Purkinje fibers
Answer: C
3. What does the P wave represent on an ECG tracing?
A) Ventricular depolarization
, B) Ventricular repolarization
C) Atrial depolarization
D) Atrial repolarization
Answer: C
4. The PR interval represents the time it takes for the electrical impulse
to travel from the:
A) SA node to the AV node
B) AV node to the Purkinje fibers
C) Atria to the ventricles (through the AV node)
D) Bundle of His to the ventricular muscle
Answer: C
5. What is the normal duration of the PR interval in an adult?
A) 0.04 - 0.10 seconds
B) 0.12 - 0.20 seconds
C) 0.20 - 0.30 seconds
D) 0.08 - 0.12 seconds
Answer: B
6. The QRS complex on an ECG represents: