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Ch 10 Cardiology
Conduction System
Question | Answer |
---|---|
small area of tissue between the right atrium and right ventricle, is part of the conduction system of the heart and receives electrical impulses from the SA node (atrioventricular) | AV node |
part of the conduction system of the heart after the bundle of His, they continue down the interventricular septum, at the apex they split into right ________ ________ to the right ventricle and the left ________ ________ to the left ventricle | bundle branches |
each bundle branch into _________ ________ that spread across the ventricles | purkinje fibers |
part of the conduction system of the heart after the Av node, it splits into right and left bundle branches | bundle of His |
system that carries the electrical impulse that makes the heart beat, it consist of the SA node, AV node, bundle of His, bundle branches, and Purkinje fibers | conduction system |
to begin a contraction of the heart, an impulse from the SA node changes permeability of the myocardial cell membrane. "+" Na ions, then "+" Ca ions, outside the cell move through the cell membrane, and more Ca ions stored in cell are released, | depolarization |
reverses the normally negative charge in a resting myocardial cell and causes a contraction | depolarization |
resting period between contractions | diastole |
area of the heart that can produce its own electrical impulse but is not part of the conduction system. sometimes overrides the impulse of the SA node and produces an abnormal heart rhythm | ectopic site |
short period of time when the myocardium is unresponsive to electrical impulses | refractory period |
to end a contraction of the heart, "+" K ions spread out of the cell, while molecular pumps move "+" Na and some Ca ions out of the cell and move the rest of the Ca ions into storage within the cell. this restores the "-" charge of a resting myocardial c | repolarizaion |
pacemaker of the heart, small area of tissue in the posterior wall of the right atrium. originates the electrical impulse for the entire conduction system of the heart | SA node |
atri/o- (upper heart chamber) | atrium |
conduct/o- | carrying; conveying |
polar/o- | positive or negative state |
diastol/o- | dilating |
ectop/o- | outside a place |
fract/o- | break up |
sin/o- | hollow cavity; channel |
systol/o- | contracting |