Electrophysiology Building Blocks Flashcards
(44 cards)
Depolarization is what of the cardiac muscles?
Contraction
Depolarization is what of the cardiac muscles?
contraction
During action potential the movement is from ____ concentration to ____ concentration.
High, Low
The inside of the cell has a negative or positive charge compared to the outside of the cell.
Negative
Which ions are concentrated inside the cell?
K+
What ions are concentrated outside the cell?
NA+ and Ca++
Responsible for rapid depolarization
Sodium channels
Responsible for repolarization
Potassium channel
What are the two types of calcium channels?
L- Type and T- Type
What is the purpose of L- Type Calcium Channels?
Contributes to contraction
What is the purpose of T-Type Calcium Channels?
Plays a significant role in automaticity and impulse conduction
What is the starting membrane potential fo a cardiac cell?
-90 mv
What happens in phase 0?
Sodium channels open allowing sodium ions to rush into the cell
What happens in phase 1?
Sodium channels close which ends the influx of sodium into the cell, the potassium ions begin to flow out of the cell
What phase marks the onset of repolarization?
Phase 1
What phase initiates depolarization?
Phase 0
What phase is know as the plateau phase?
Phase 2
What happens in phase 2?
Calcium channels open and allow the influx of calcium ions into the cell.
What phase is known as the absolute refractory period?
Phase 2
What happens in phase 3?
The calcium channels close and the potassium ions continue to exit the cell. The sodium potassium pump pushes NA out of the cell and pulls K+ ions back into the cell at a 3 Na: 1K
In what phase is depolarization complete?
Phase 3
What phase is also known as the Quiescent period?
Phase 4
What happens in phase 4?
The cell returns to its resting membrane of -90 mV and the distribution of the Na+ and K+ is restored and the cell can now be depolarized again
What phase is the resting membrane potential?
Phase 4
