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ECG ORIENTATION KAISER TEST
QUESTIONS AND ANSWERS
DEPOLARIZATION - Answers✓✓Movement of ions (Na+, Ca+, K+) across cell membrane
causing inside of cell to become more positive, electrical conduction results in contraction. Na+
channels open. Positive inside, negative outside.
REPOLARIZATION - Answers✓✓movement of ions across cell membrane where inside of cell
is restored to its negative charge. Sodium channels close. Potassium channels open. Active
transport by sodium-potassium pump
DEPORIZATION - Answers✓✓ELECTRICAL
CONTRACTION - Answers✓✓IS MECHANICAL. CONTRACTION FOLLOWS
DEPOLARIZATION.
WHAT OCCUR FIRST? ELECTRICAL CONDUCTION, OR MECHANICAL
CONTRACTION? - Answers✓✓ELECTRICAL CONDUCTION
P WAVE - Answers✓✓ATRIAL DEPOLARIZATION
QRS - Answers✓✓VENTRICAL DEPOLARIZATION
T WAVE - Answers✓✓ventricular repolarization
REFRACTORY PERIOD - Answers✓✓the period of resistance to stimulation, cardiac cells
unable to respond to stimulus
, ©Themoon EXAM SOLUTIONS
12/11/2024 8:10PM
relative refractory period - Answers✓✓cardiac cells have repolarized enough to respond to
strong stimulus
automaticity - Answers✓✓Ability of pacemaker cells to spontaneously initiate an electrical
impulse, SA node, AV junction, and Purkinje fibers
excitability - Answers✓✓ability to respond to stimuli
conductivity - Answers✓✓Ability to receive an electrical stimulus and conduct that impulse to
adjacent cells - all cardiac cells possess this.
contraction - Answers✓✓Cardiac cells shorten, causing muscular contraction in response to an
electrical stimulus
SA node - Answers✓✓Sino-atrial node; the pace-maker of the heart; where the impulse
conduction of the heart usually starts; located in the top of the right atrium. 60-100 bpm
AV node - Answers✓✓(atrioventricular node) region of the heart between the right atrium and
right ventricle from which electrical impulses spread to the ventricles during a heartbeat. 40-
60bpm
bundle of HIS - Answers✓✓Ability to self initiate electrical activity Rate: 40 - 60 beats per
minutes
Purkinje fibers - Answers✓✓fibers that carry stimulation throughout the ventricles. 20-40bpm
junctional rhythm HR - Answers✓✓40-60bpm
ventricular rhythm - Answers✓✓20-40bpm