During an action potential, the inside of the cell membrane becomes more positive than the outside. Why does this happen? a. During depolarization, the sodium ions rush in and the potassium ions have not begun rushing out, making the inside more positive. b. During depolarization, the sodium ions rush in and the potassium ions have not begun rushing out, making the outside more positive. c. During depolarization, the potassium ions rush in and the sodium ions have begun rushing out, making the inside more positive. d. During depolarization, the sodium ions rush in and the potassium ions have begun rushing out, making the outside more positive.

Use this illustration to place these events in the order they occur during synaptic communication: Column A Column B a. Voltage gated sodium channels carry the action potential to the synapse by allowing the influx of sodium ions. 1. 1 2 b. An increase in calcium levels triggers vesicle release. 3. 3 c. Sodium enters the post-synaptic cell, causing it to depolarize. 4. 4 d. Sodium influx at the synapse activates voltage gated 5. calcium channels which allow calcium ions to enter the presynaptic neuron. 6. 6. e. Neurotransmitters are released into the synaptic cleft. f. Ligand-gated ion channels are opened by the neurotransmitters. 2.

Which of the following allows the cell to recover from hyperpolarization during an action potential?   A. Stimulus gated sodium channels B. voltage gated sodium channels C. voltage gated potassium channels D. sodium/potassium pump

Describe what allows an action potential to move quickly along the membrane in one direction (why doesn't it move backwards?)