1.9k views
4 votes
The permeability to _______ is most important for generating the peak positive potential during an action potential?

1 Answer

4 votes

Final answer:

The peak positive potential during an action potential is generated by the permeability to sodium ions (Na+), which enter the cell through voltage-gated sodium channels, causing depolarization.

Step-by-step explanation:

The permeability to sodium ions (Na+) is most important for generating the peak positive potential during an action potential. At the onset of an action potential, voltage-gated sodium channels open, allowing Na+ to rush into the neuron. This causes a rapid rise in the membrane potential, creating a positive spike known as the peak of the action potential. Following this peak, these sodium channels close, and voltage-gated potassium channels open, leading to the efflux of K+, which helps to repolarize the membrane, returning it to its resting state. This coordinated opening and closing of Na+ and K+ channels are essential for the propagation of action potentials along the axon, enabling neural communication.

Additionally, the sodium-potassium pump (Na+/K+ transporter) actively maintains the resting membrane potential by moving Na+ out of and K+ into the cell against their respective concentration gradients, using ATP as an energy source. This pump is crucial for resetting the concentrations of Na+ and K+ after each action potential, ensuring that the neuron is ready for subsequent firing.

User Gronostaj
by
7.8k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.