NROSCI 1000 Lecture Notes - Lecture 4: Threshold Potential, Axon Terminal, Resting Potential
Document Summary
Membrane potential that exactly opposes diffusive force; opposite direction, same magnitude. Electrical force pulling k (a positive ion) into the cell (opposite of. Diffusive force) which is why the number is negative. Example: the equilibrium potential of chloride is negative diffusive force is out to in; electrical force is in to out therefore the inside of the cell needs to be negative. Intiation and propogation is due ti voltage gated ion channels. Vgic open and close in response to in voltage of membrane potential (na+, k+) Sodium really wants to be inside the cell. Yet the cell is very impermiable to sodium and the rest of it gets pumped back out. Yet if its larger than 10 mv, it reaches the threshold potential. If you get enough stimulation to reach the threshold you get an action potential. If the cell reaches its threshold it will have an action potential. It is a change in the membrane potential.
