When thinking about an action potential which one of the following statements is TRUE?Question 10Answera.A stimulus changes the permeability of a "patch" of the membrane, and sodium ions (Na+) diffuse rapidly into the cell.b.During repolarization, sodium ions diffuse rapidly into the cell.c.If a stimulus is strong enough, hyperpolarization causes membrane polarity to be completely reversed, and an action potential is initiated.d.Ionic conditions are restored after repolarization by the actions of the sodium-potassium (Na+-K+) pump, whereby two Na+ ions are ejected for every three K+ ions carried back into the cell.e.The external side of the resting membrane is slightly negative, and its internal side is slightly positive.

dentify why the membrane becomes hyperpolarized following the repolarization phase of an action potential.Multiple choice question.Voltage-gated K+ channels remain open for a short period of time after reaching RMP; allowing K+ to diffuse out of the cell.Voltage-gated Na+ channels remain open for a short period of time after reaching RMP; allowing Na+ to diffuse out of the cell.Voltage-gated Na+ channels remain open for a short period of time after reaching RMP; allowing Na+ to diffuse into the cell.Voltage-gated K+ channels remain open for short period of time after reaching RMP; allowing K+ to diffuse into the cell.

109. One reason that action potentials are all-or-none is that a. they are always the same size in a given neuron. b. axonal membranes do not allow partial electrical responses to electrical stimuli. c. they must travel long distances without decrement. *d. once the membrane potential is past threshold, the influx of Na+ keeps driving it more positive until the maximum number of Na+ channels is

A recently depolarized area of a cell membrane cannot generate an action potential because of theMultiple Choiceabsolute refractory period.high concentration of sodium ions in the extracellular fluid.the high concentration of potassium ions in the cytoplasm.presence of receptor sites on the membrane.

Sodium ions move into a neuron during Blank______.Multiple choice question.repolarizationdepolarization

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 .