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10 Cards in this Set
- Front
- Back
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What initiates the heartbeat?
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spontaneous depolarization of the sino-atrial node
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Speed of conduction of the purkinje fibers?
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5 m/s
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speed of conduction at the SA node
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.05 m/s
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what is the speed of conduction across the atrium?
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1 m/s
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what is the speed of conduction across the AV node?
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.01-.05
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what happens at phase 0 of ventricular contraction?
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Na comes in
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what happens at phase 1 of ventricular contraction?
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K+ influx slow and fast
as well as Cl- |
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what happens at phase 2 of ventricular contraction?
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this is plateau
you have Ca in, and a late Na Channel yet you also have 2 K channels to balance the Na this keeps it in plateau |
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what happens at phase 3 of ventricular contraction?
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2 K channels open, leading to repolarization
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what happens at phase 4 of ventricular contraction?
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There is an inward K rectifier to keep a steady baseline
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