NROB60H3 Chapter Notes - Chapter 4: University Of Manchester, Electrical Resistance And Conductance
Document Summary
Action potential generated by a cell are all similar in size and duration. Do no diminish as they are conducted down the axon. Frequency and pattern of aps constitute the code used by neurons to transfer info form 1 location to another. The ups and downs of an action potential. Membrane potential, vm, can be determine by insetting a microelectrode in the cell. Voltmeter is used o measure electrical potential difference b/w tip of intracellular micro=electrode and another placed outside cell. The action potential has certain identifiable parts: rising phase: rapid depolarization of the membrane, continue until. Vm reaches a peak value of ~40 mv. Overshoot: part of ap where inside of neuron is (+)-charged outside: falling phase: rapid repolarization until the membrane is actually more (-) than resting potential, after-hyperpolarization/undershoot: last part of falling phase, gradual restoration of resting potential. Threshold: critical level of depolarization that must be crossed in order to trigger an ap.