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8 Cards in this Set
- Front
- Back
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1. Generates rhythmical electrical impulses to initiate rhythmical contraction of the heart muscle 2. Conducts these impulses rapidly through the heart |
2 functions of the system that performs the rhythmical excitation of the heart |
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1/6 of a second |
atria contract about _______________ ahead of ventricular contraction |
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Internodal pathways |
conduct impulses from the sinus node to the atrioventriculear (A-V) node |
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A-V bundle |
conducts impulses from the atria into the ventricles |
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Bundle branches of Purkinje fibers |
conduct cardiac impulses to all parts of the ventricles |
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Sinus (Sinoatrial) Node |
small, flattened, ellipsoid strip of specialized cardiac muscle |
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3 mm wide, 15 mm long and 1 mm thick |
dimensions of sinoatrial node |
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Superior posterolateral wall of the right atrium immediately below and slightly lateral to the opening of the superior vena cava |
location of the sinoatrial node |
