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Flashcards in Terminology Deck (11):
1

Functional refractory period
FRP

The coupling interval which first results in a measurable degree of delay in impulse conduction

2

Effective refractory period
ERP

The longest coupling intervals to be associated with block

3

Resting transmembrane potential

Voltage difference between the inside and outside of the cell fiber

4

Action potential

Cellular characteristics of depolarization and repolarization. The action potential consist of five phases

5

Definition of phase 0 of action potential

The depolarization phase, during this phase the rapid sodium channels are stimulated to open, causing the resting transmembrane potential to spike from -90 mV to 20 mV

6

Definition of phase 1 of the action potential

Early repolarization

7

Definition ofPhase 2Of the action potential

The plateau phase. This phase, mediated by the slow calcium channels, essentially disrupts and delays the repolarization started in phase 1 and prolongs the refractory period

8

Definition of phase 3 of the action potential

The end of repolarization.

9

Which phases of the action potential represent the refractory period of cardiac tissue?

The end of phase 0 through the end of phase 3 represents the refractory period Of cardiac tissue

10

Definition of phase 4 of the action potential

The resting phase. It is during this phase that and some cardiac cells ions lake back-and-forth between membranes and cause a gradual increase in the transmembrane resting potential. When the potential voltage reaches the threshold voltage the cell repolarizes.

11

Define automaticity

Spontaneous depolarization of the cell membrane