I am learning about the Nernst equilibrium in a neuron (along with the Goldman equation), and while I understand certain concepts individually, I struggle to bring it all together. The Nernst equilibrium is defined in terms of the reversal potential. That is, the membrane potential value needed to bring the net to 0. So, if there is a concentration gradient which generates the potential of 80mV, the Nernst equilibrium (reversal potential) would have a value of -80mV. Is this correct?
Now, the deviation from this equilibrium results in the electrochemical driving force. that is the difference between the membrane potential (which is the actual electrical potential) and the reversal potential. how is the membrane potential interrelated to the concentration gradient? Is the concentration gradient facilitated by the permeability of ions creating the membrane potential as a result?
Lastly, is the conductance of ions simply the degree to which the permeability to particular ion is allowed, and is modulated by the state of the membrane potential - Hyperpolarisation causes one particular ion to enter, depolarisation another.
I know there are several points and questions made here. I hope that it is relatively structured. As I have said, I myself struggle to put it all together in a coherent manner and make it more intuitive.