Problem:

Question 1: Why are action potentials transient, self-propagating, and energy efficient? Do many ions have to cross a membrane through an ion channel to change the membrane potential?

Question 2: A mutation causes a delay in the opening of the voltage-gated K-channel after membrane depolarization. How would this change the time course of an action potential?

Question 3: What would an action look like if the voltage-gated Na-channels inactivated slowly? If the voltage-gated K-channels inactivated slowly?

Provide a brief explanation for your answer.