Answers | Verified Q&A Study Guide | Passed 2025/2026
1. The study of the heart is called:
A) Cardiology
B) Electrocardiography
C) Cardiovascular physiology
D) Echocardiography
Correct Answer: A
Rationale: Cardiology is the medical specialty that deals with the study, diagnosis, and treatment of
disorders of the heart and circulatory system.
2. An electrocardiogram (EKG/ECG) is a graphic illustration of:
A) The mechanical activity of the heart
B) The electrical activity of the heart
C) The blood flow through the heart chambers
D) The oxygen saturation of the blood
Correct Answer: B
Rationale: An EKG records the electrical activity of the heart, not its mechanical pumping action. The
electrical impulses trigger the mechanical contractions.
,3. The heart's electrical conduction system begins with which structure?
A) Atrioventricular (AV) node
B) Bundle of His
C) Sinoatrial (SA) node
D) Purkinje fibers
Correct Answer: C
Rationale: The sinoatrial (SA) node is the heart's natural pacemaker. It generates electrical impulses that
initiate each heartbeat and set the rhythm for the entire heart.
4. What is the normal resting heart rate for a healthy adult?
A) 40–60 beats per minute
B) 60–100 beats per minute
C) 80–120 beats per minute
D) 100–140 beats per minute
Correct Answer: B
Rationale: A normal resting heart rate for adults ranges from 60 to 100 beats per minute. Rates below
60 may indicate bradycardia, and rates above 100 may indicate tachycardia.
5. The P wave on an EKG represents:
A) Ventricular depolarization
,B) Atrial depolarization
C) Ventricular repolarization
D) Atrial repolarization
Correct Answer: B
Rationale: The P wave represents atrial depolarization, which is the electrical activity that triggers
contraction of the atria. It is the first positive deflection seen on a normal EKG tracing.
6. The QRS complex on an EKG represents:
A) Atrial depolarization
B) Ventricular depolarization
C) Atrial repolarization
D) Ventricular repolarization
Correct Answer: B
Rationale: The QRS complex represents ventricular depolarization, which triggers the contraction of the
ventricles. This is the largest waveform on the EKG due to the greater muscle mass of the ventricles.
7. The T wave on an EKG represents:
A) Atrial depolarization
B) Ventricular depolarization
C) Ventricular repolarization
D) Atrial repolarization
, Correct Answer: C
Rationale: The T wave represents ventricular repolarization, which is the recovery phase of the
ventricles as they prepare for the next heartbeat. It is a positive deflection following the QRS complex.
8. What is the normal duration of the PR interval?
A) 0.04–0.10 seconds
B) 0.06–0.12 seconds
C) 0.12–0.20 seconds
D) 0.20–0.40 seconds
Correct Answer: C
Rationale: The normal PR interval (from the beginning of the P wave to the beginning of the QRS
complex) is 0.12 to 0.20 seconds (3 to 5 small boxes on standard EKG paper).
9. What is the normal duration of the QRS complex?
A) Less than 0.06 seconds
B) Less than 0.10 seconds
C) Less than 0.12 seconds
D) Less than 0.20 seconds
Correct Answer: C
Rationale: The normal QRS duration is less than 0.12 seconds (3 small boxes on standard EKG paper). A
widened QRS complex may indicate a bundle branch block or ventricular origin of the rhythm.