cardiovascular (slides) ppt. 2
myogenic - ANS heartbeat originates within heart
autorhythmic - ANS regular, spontaneous depolarization
pacemaker of heart - ANS SA node
SA node - ANS initiates heartbeat, sets heart rate
AV node - ANS electrical gateway to ventricles
what does the AV node have a brief delay - ANS allows the atria can contract before the ventricles
AV bundle is aka... - ANS Bundle of His
AV bundle (bundle of His) - ANS pathway for signals from AV node
right and left bundle branches - ANS divisioms of AV bundle that enter interventricular septum
Purkinje fibers - ANS upward from apex, spread throughout ventricular myocardium in order to
maximize ventricular ejection
1st step of cardiac conduction system - ANS SA node activity and atrial activation begins
, 2nd step of cardiac conduction system - ANS stimulus spreads across atrial surfaces and reaches the AV
node
3rd step of cardiac conduction system - ANS 100 msec delay at the AV node, atrial contraction begins
4th step of cardiac conduction system - ANS impulse travels along the interventricular septum within
the AV bundle and the bundle branches to the purkinje fibers and to the papillary muscles of the right
ventricle
5th step of cardiac conduction system - ANS impulse is distributed by purkinje fibers and relayed
throughout the ventricular myocardium, atrial contraction completes and ventricular contraction begins
stable resting potential of myocytes - ANS -90mv
Step 1 of cardiac action potential - ANS depolarization (veri brief)
what causes depolarization of a cardiac cell? - ANS Na+ gates open and Na+ rushes in and gates close
quickly
peak of cardiac action potential - ANS +30mV
Step 2 of cardiac action potential - ANS plateau (200-250 msec long)
what happens during the plateau of a cardiac action potential? - ANS Contraction: Slow Ca2+ channels
open, Ca2+ binds to fast Ca2+ channels on SR, releases Ca2+ into cytosol
Step 3 of cardiac action potential - ANS repolarization
myogenic - ANS heartbeat originates within heart
autorhythmic - ANS regular, spontaneous depolarization
pacemaker of heart - ANS SA node
SA node - ANS initiates heartbeat, sets heart rate
AV node - ANS electrical gateway to ventricles
what does the AV node have a brief delay - ANS allows the atria can contract before the ventricles
AV bundle is aka... - ANS Bundle of His
AV bundle (bundle of His) - ANS pathway for signals from AV node
right and left bundle branches - ANS divisioms of AV bundle that enter interventricular septum
Purkinje fibers - ANS upward from apex, spread throughout ventricular myocardium in order to
maximize ventricular ejection
1st step of cardiac conduction system - ANS SA node activity and atrial activation begins
, 2nd step of cardiac conduction system - ANS stimulus spreads across atrial surfaces and reaches the AV
node
3rd step of cardiac conduction system - ANS 100 msec delay at the AV node, atrial contraction begins
4th step of cardiac conduction system - ANS impulse travels along the interventricular septum within
the AV bundle and the bundle branches to the purkinje fibers and to the papillary muscles of the right
ventricle
5th step of cardiac conduction system - ANS impulse is distributed by purkinje fibers and relayed
throughout the ventricular myocardium, atrial contraction completes and ventricular contraction begins
stable resting potential of myocytes - ANS -90mv
Step 1 of cardiac action potential - ANS depolarization (veri brief)
what causes depolarization of a cardiac cell? - ANS Na+ gates open and Na+ rushes in and gates close
quickly
peak of cardiac action potential - ANS +30mV
Step 2 of cardiac action potential - ANS plateau (200-250 msec long)
what happens during the plateau of a cardiac action potential? - ANS Contraction: Slow Ca2+ channels
open, Ca2+ binds to fast Ca2+ channels on SR, releases Ca2+ into cytosol
Step 3 of cardiac action potential - ANS repolarization
