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SHARP EKG Exam 2026 (Actual Exam) Questions
with verified Answers (Latest Update 2026)
UPDATE!!
What are the two basic kinds of cardiac cells? - ANSWER -1. myocardial
muscle cells
2. myocardial pacemaker cells
What are the 4 primary cell characteristics? - ANSWER -1. Automaticity
2. Excitability
3. Conductivity
4. Contractility
What are the two major ions that affect cardiac function? - ANSWER -1.
sodium
2. potassium
What are the primary ions inside the cell? - ANSWER -Potassium
What are the primary ions outside the cell? - ANSWER -Sodium
Distribution of ions on either side of the membrane is determined by
which several factors? - ANSWER -1. membrane channels
pg. 1
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2. concentration gradient
3. electrical gradient
4. sodium-potassium pump
Where is the SA node located? - ANSWER -In the upper wall of the right
atrium/near the inlet of the superior vena cava
What is the intrinsic rate of the SA node? - ANSWER -60-100 bpm
Pacemaker cells in the AV junction generate electrical impulses at what
rate? - ANSWER -40-60 bpm
What are the 3 functions of the AV node? - ANSWER -1. slow
conduction of the electrical impulse through the AV node to allow atria
to empty into the ventricles (atrial kick)
2. to serve as a back pack pacemaker
3. protect ventricles from fast rates
After the delay in the AV node, where does the impulse go? - ANSWER -
To the bundle of His
What is the function of the bundle of His? - ANSWER -The Bundle of His
(AV Bundle) runs from the AV node through the IV septum, splitting into
pg. 2
,3|Page
R. and L. branches and eventually breaking into Purkinje fibers as it
spreads through the ventricular walls
What is the rate of electrical impulse the Purkinje Fibers have? -
ANSWER -30-40 bpm
What does the P wave represent? - ANSWER -atrial depolarization
When does atrial repolarization occur? - ANSWER -during the QRS
complex
What does the QRS wave represent? - ANSWER -ventricular
depolarization
What does the ST segment represent? - ANSWER -early ventricular
repolarization
What does the T wave represent? - ANSWER -ventricular repolarization
What does the QT interval represent? - ANSWER -the time of
*ventricular activity* including both depolarization and repolarization
What are the two refectory phases of the cardiac cycle? - ANSWER -1.
Absolute refractory period
pg. 3
, 4|Page
2. Relative refractory period
What is "absolute refractory period"? - ANSWER -The cardiac cells are
unable to respond to an electrical stimulus (from the onset of the QRS
to the peak of the T wave)
What is the "relative refractory period"? - ANSWER -The cardiac cells
have depolarized sufficiently to respond to a strong stimulus (peak of T
wave to end of T wave)
A small square on EKG paper is how long? - ANSWER -0.04
A big square on EKG paper is how long? - ANSWER -0.2
How long is a P wave? - ANSWER -< .10
What is the duration of the PR interval? - ANSWER -0.12-0.20
What is the duration of the QRS? - ANSWER -< .10
What are some causes of a abnormally wide QRS? - ANSWER -1. a
electrical impulse that originated in an ectopic site in the ventricles
2. BBB
pg. 4
SHARP EKG Exam 2026 (Actual Exam) Questions
with verified Answers (Latest Update 2026)
UPDATE!!
What are the two basic kinds of cardiac cells? - ANSWER -1. myocardial
muscle cells
2. myocardial pacemaker cells
What are the 4 primary cell characteristics? - ANSWER -1. Automaticity
2. Excitability
3. Conductivity
4. Contractility
What are the two major ions that affect cardiac function? - ANSWER -1.
sodium
2. potassium
What are the primary ions inside the cell? - ANSWER -Potassium
What are the primary ions outside the cell? - ANSWER -Sodium
Distribution of ions on either side of the membrane is determined by
which several factors? - ANSWER -1. membrane channels
pg. 1
,2|Page
2. concentration gradient
3. electrical gradient
4. sodium-potassium pump
Where is the SA node located? - ANSWER -In the upper wall of the right
atrium/near the inlet of the superior vena cava
What is the intrinsic rate of the SA node? - ANSWER -60-100 bpm
Pacemaker cells in the AV junction generate electrical impulses at what
rate? - ANSWER -40-60 bpm
What are the 3 functions of the AV node? - ANSWER -1. slow
conduction of the electrical impulse through the AV node to allow atria
to empty into the ventricles (atrial kick)
2. to serve as a back pack pacemaker
3. protect ventricles from fast rates
After the delay in the AV node, where does the impulse go? - ANSWER -
To the bundle of His
What is the function of the bundle of His? - ANSWER -The Bundle of His
(AV Bundle) runs from the AV node through the IV septum, splitting into
pg. 2
,3|Page
R. and L. branches and eventually breaking into Purkinje fibers as it
spreads through the ventricular walls
What is the rate of electrical impulse the Purkinje Fibers have? -
ANSWER -30-40 bpm
What does the P wave represent? - ANSWER -atrial depolarization
When does atrial repolarization occur? - ANSWER -during the QRS
complex
What does the QRS wave represent? - ANSWER -ventricular
depolarization
What does the ST segment represent? - ANSWER -early ventricular
repolarization
What does the T wave represent? - ANSWER -ventricular repolarization
What does the QT interval represent? - ANSWER -the time of
*ventricular activity* including both depolarization and repolarization
What are the two refectory phases of the cardiac cycle? - ANSWER -1.
Absolute refractory period
pg. 3
, 4|Page
2. Relative refractory period
What is "absolute refractory period"? - ANSWER -The cardiac cells are
unable to respond to an electrical stimulus (from the onset of the QRS
to the peak of the T wave)
What is the "relative refractory period"? - ANSWER -The cardiac cells
have depolarized sufficiently to respond to a strong stimulus (peak of T
wave to end of T wave)
A small square on EKG paper is how long? - ANSWER -0.04
A big square on EKG paper is how long? - ANSWER -0.2
How long is a P wave? - ANSWER -< .10
What is the duration of the PR interval? - ANSWER -0.12-0.20
What is the duration of the QRS? - ANSWER -< .10
What are some causes of a abnormally wide QRS? - ANSWER -1. a
electrical impulse that originated in an ectopic site in the ventricles
2. BBB
pg. 4
