Final Answer:
The opening of voltage-gated K+ channels allows the outward flow of K+ and the Na/K pump to maintain the resting membrane potential of a neuron.
Step-by-step explanation:
When a neuron is at rest, the concentration gradient and electrical gradient for K+ are balanced, resulting in a resting membrane potential of approximately -70mV. When voltage-gated K+ channels open, K+ ions move out of the cell down their concentration gradient, leading to hyperpolarization. This outward movement of positive charge contributes to repolarization and helps restore the resting membrane potential. Additionally, the Na/K pump actively transports 3 Na+ out of the cell and 2 K+ into the cell, maintaining the concentration gradients necessary for the resting membrane potential.
The Nernst equation can be used to calculate the equilibrium potential for K+. The equation is EK = (RT/zF) * ln([K+]out/[K+]in), where R is the gas constant, T is temperature in Kelvin, z is the valence of the ion, F is Faraday’s constant, [K+]out is the extracellular potassium concentration, and [K+]in is the intracellular potassium concentration. By plugging in the appropriate values, we can calculate EK and understand how changes in K+ concentrations affect the resting membrane potential.
The Goldman-Hodgkin-Katz (GHK) equation can also be used to calculate the resting membrane potential by taking into account multiple ions and their permeabilities. This equation provides a more accurate representation of the resting membrane potential by considering both K+ and Na+ ions. By understanding these principles and equations, we can appreciate how voltage-gated K+ channels and the Na/K pump play crucial roles in maintaining the resting membrane potential of neurons.