What is the correct sequence of events that occurs along an axon after the membrane reaches threshold?The membrane depolarizes.Sodium channels open and sodium ions diffuse inward.The membrane repolarizes.Potassium channels open and potassium ions diffuse outward.Multiple Choice4, 1, 3, 21, 2, 4, 33, 2, 4, 12, 1, 4, 3

Complete the sentences describing the events that occur during an action potential.An action potential will not occur unless the membrane potential at the (the initial segment of the axon) reaches a level called .When threshold is reached, of the initial segment open briefly, allowing to diffuse into the cell.As these ions enter the cell, the cell membrane undergoes , with the membrane potential increasing to a peak of approximately +30mV.As the peak of the action potential is reached, the sodium channels close and the open, allowing these ions to diffuse out of the cell.As cations leave the cell, the membrane potential at that part of the membrane once again becomes negative. This phase of the action potential is called , because the resting membrane potential is being reestablished.The membrane potential actually dips lower than -70mV because the potassium channels do not close quickly enough. This phase is called .

Opening of sodium channels in the axon membrane causes: Question 26Select one:a.depolarization.b.repolarization.c.hyperpolarization.d.increased negative charge inside the membrane.e.inhibition.

When traveling along an axon, the cell membrane immediately ahead of an action potential depolarizes because of _________blank.Multiple Choicethe sodium/potassium pumpmembrane receptorsdiffusion of sodium currentdecreased membrane permeabilitypotassium efflux

Place the following events in excitatory synaptic transmission in order: 1 - A postsynaptic potential is produced. 2 - Voltage-gated calcium channels open and calcium enters the cell. 3 - ACh is released and diffuses across the axon terminal. 4 - A nerve signal arrives at an axon terminal. 5 - Ligand-gated sodium channels open and sodium enters the cell.

Arrange these action potential events in their proper sequence: (1) The neuron is stimulated at the dendrites (2) K+ gates open (3) The neuron is in a polarized “resting” state (4) Na+ gates open (5) The cell is fully depolarized (6) The cell is fully repolarized a. 1, 2, 4, 3, 5, 6b. 3, 1, 4, 5, 2, 6c. 4, 6, 2, 1, 5, 3d. 1, 4, 2, 6, 5, 3