Module 1. The Calculated Action Potential

Observe.

Module 2. The Threshold of the Action Potential

Completely label the axes and plot the minimum stimulus amplitude required to reach threshold at various stimulus durations.

Module 3. Currents of the Action Potential.

Which is the inward (negative) current? The outward? Depolarizing or hyperpolarizing?

Module 4. The Initiation of the Action Potential

Which current grows more quickly?

Describe briefly why the increase in sodium current is regenerative:

Module 5. The Sodium Current

Sketch the sodium conductance, driving force and current in relation to the time course of the action potential:

Why is the notch in the sodium current?

Module 6. The Relative and Absolute Refractory Periods.

Module 7. Accommodation.

What are 2 reasons for accommodation? (Check the more important reason.)

[A]

Why is the absolute refractory so utterly complete?

Module 8. Pacing a Train of Action Potentials?

By how much can you vary the action potential frequency? How does this compare with the variability of the heart rate?

Module 9. Inhibitory Currents of the Action Potential.

Plot the relationship between threshold and the conductance of the inhibitory current when the IPSP reversal potential is -80 mV and when it is -90 mV.

Why should increasing the conductance of a synapse be inhibitory if the reversal potential is the same as the resting potential?

Can you cause a regenerative action potential in the presence of 500 mA/cm2 of inhibitory current?

What does the last answer mean with regards the explanation for the refractory period?

End