Podcast
Questions and Answers
What best describes the 'all or nothing' principle of action potentials?
What best describes the 'all or nothing' principle of action potentials?
- An action potential occurs only if a stimulus reaches a certain minimum intensity. (correct)
- Action potentials vary in intensity depending on the strength of the stimulus.
- All stimuli, regardless of strength, produce an action potential.
- Action potentials can be stopped once initiated.
During an action potential, what causes rapid depolarization?
During an action potential, what causes rapid depolarization?
- Closing of potassium channels
- Opening of chloride channels
- Rapid influx of sodium ions through voltage-gated channels (correct)
- Efflux of calcium ions
What is the primary cause of repolarization during an action potential?
What is the primary cause of repolarization during an action potential?
- Influx of sodium ions
- Efflux of potassium ions (correct)
- Influx of chloride ions
- Efflux of sodium ions
What is the significance of the absolute refractory period?
What is the significance of the absolute refractory period?
How do myelinated nerve fibers enhance conduction?
How do myelinated nerve fibers enhance conduction?
Which phase is characterized by increased permeability to potassium ions?
Which phase is characterized by increased permeability to potassium ions?
What triggers the opening of voltage-gated sodium channels at the beginning of an action potential?
What triggers the opening of voltage-gated sodium channels at the beginning of an action potential?
What is the significance of the relative refractory period?
What is the significance of the relative refractory period?
What is the role of myelin in the conduction of action potentials along nerve fibers?
What is the role of myelin in the conduction of action potentials along nerve fibers?
During an action potential, what is the primary cause of the initial rapid depolarization?
During an action potential, what is the primary cause of the initial rapid depolarization?
What results from the opening of voltage-gated potassium channels during an action potential?
What results from the opening of voltage-gated potassium channels during an action potential?
During an action potential, what is the function of the sodium-potassium pump?
During an action potential, what is the function of the sodium-potassium pump?
How does the absolute refractory period contribute to action potential directionality?
How does the absolute refractory period contribute to action potential directionality?
What effect does myelin have on nerve fiber capacitance and resistance?
What effect does myelin have on nerve fiber capacitance and resistance?
Why is conduction faster in myelinated nerve fibers?
Why is conduction faster in myelinated nerve fibers?
What causes hyperpolarization during the action potential?
What causes hyperpolarization during the action potential?
How does the absolute refractory period affect action potential frequency?
How does the absolute refractory period affect action potential frequency?
What is the role of voltage-gated sodium channels in action potentials?
What is the role of voltage-gated sodium channels in action potentials?
What determines action potential propagation speed in a nerve fiber?
What determines action potential propagation speed in a nerve fiber?
What is unique about action potential propagation in myelinated fibers?
What is unique about action potential propagation in myelinated fibers?
What is the effect of the plateau phase in cardiac action potentials?
What is the effect of the plateau phase in cardiac action potentials?
During depolarization, what change occurs in membrane permeability?
During depolarization, what change occurs in membrane permeability?
What characterizes the relative refractory period?
What characterizes the relative refractory period?
How does axon diameter affect conduction velocity in non-myelinated fibers?
How does axon diameter affect conduction velocity in non-myelinated fibers?
What factor contributes to high conduction velocity in myelinated fibers?
What factor contributes to high conduction velocity in myelinated fibers?
How does hyperosmotic damage in diabetes affect nerve conduction?
How does hyperosmotic damage in diabetes affect nerve conduction?
What is the relation between axon diameter and conduction velocity in non-myelinated fibers?
What is the relation between axon diameter and conduction velocity in non-myelinated fibers?
Why is conduction velocity increased in myelinated fibers?
Why is conduction velocity increased in myelinated fibers?
What is the effect of increasing stimulus intensity on action potential frequency?
What is the effect of increasing stimulus intensity on action potential frequency?
What role does the time constant play in action potential propagation?
What role does the time constant play in action potential propagation?
What effect does the action potential have on sodium-potassium pump activity?
What effect does the action potential have on sodium-potassium pump activity?
What causes the 'undershoot' phase after an action potential?
What causes the 'undershoot' phase after an action potential?
How does action potential frequency correlate with stimulus intensity?
How does action potential frequency correlate with stimulus intensity?
What role does the time constant play in nerve signal transmission?
What role does the time constant play in nerve signal transmission?
What is the primary role of voltage-gated potassium channels during an action potential?
What is the primary role of voltage-gated potassium channels during an action potential?
