Action Potential Curve Flashcards
What happens in phase 0
cardiac cell RAPID DEPOLARIZATION
what enters and leaves in phase 0
Na+ enters and K+ leaves
Phase 0-1 is
RAPID REPOLARIZATION
what enters and leaves in phase 0-1
K+ reenters and Na+ leaves
Phase 2 aka
the plateau phase
In phase to what enters
ca+
in phase 2 ca+ enters causing
cell CONTRACTION
Ca+ causing cell contraction is the
excitation-contraction coupling mechanism
Phase 2 coincides with the
ST segment
Phase 3
final RAPID REPOLARIZATION
What enters and leaves during phase 3
Na+ and Ca+ are pumped out of the cell and K+ returns
Phase 4 AKA
resting phase
What enters and leaves in phase 4
Na+ and Ca+ remain outside the cell while K+ remains inside
During phase 1 and 2 : the cardiac cell will not respond to another stimulus no matter how strong
ABSOLUTE REFRACTORY PERIOD
during phase 2 and 3 the cardiac cell CAN be stimulated again but the stimulus must be stronger than usual
RELATIVE REFRACTORY PERIOD