Discuss the events in an action potential that are generated in cardiac contractile cells.

In a cardiac contractile cell what is the mechanism involved in the change in membrane potential? Depolarization: P wave Repolarization: QRS Complex, Hyperpolarization: T wave Pacemaker: K+ and Na+ flow, Depolarization: Pca rises Repolarization: Pk rises Depolarization: Pna increases, Peak: Na channels close, Plateau: Calcium channels close & Potassium channels open, Repolarization Potassium flows out & Calcium flows in Pacemaker: K+ and Na+ flow, Depolarization: Pca rises Repolarization: Pk rises, 4. If channels close Depolarization: Pna increases, Peak: Na channels close, Plateau: Calcium channels open & Potassium channels close, Repolarization Potassium flows out & Calcium flows out

Once you have studied the wiggers diagram   Create your own outline of the steps with a brief explanation of each step. Why each step occurs when it does; example p-wave occurs before atrial contraction becasue it is the indication that electrical current traveled through the atria to cause atrial depolorization. You should cover all major steps from start to end of a single cardiac cycle. number of steps you include are up to you depending on how you are looking at it, but make sure all major steps are covered

Discuss the mechanism underlying AP generation by cardiac autorhythmic cells

The entry of calcium into a ventricular muscle cell helps to maintain depolarization of the membrane during the plateau phase of the action potential, but this calcium also performs what other function?

Detail action potential of myocardial conduction and contractile cells – see stages. Include all ion movement in your answer.

Compare the effects of hypokalemia and hyperkalemia on the membrane potential and excitability of a cardiac muscle cell.

Describe the conditions at the sarcolemma of cardiac muscle cells at rest.

The role of calcium currents in cardiac contractile cells is to .  The role of calcium currents in cardiac conductive cells is to .    Choose between: release neurotransmitter, bring the membrane potential to threshold, initiate action potential, prolong action potential, terminate action potential

The cardiac action potential is substantially longer than a neuron potential due to: spontaneous depolarization Ca++ entry gap junctions myocardial contractility