COGS 11 Lecture Notes - Lecture 7: Cannabinoid, Axon Hillock, Tandem Pore Domain Potassium Channel
Document Summary
40% of energy goes into maintaining the differential in neurons. Taken by the pump from the atp. Equilibrium potential (-> no net change), for every ion that comes in, one comes out. Nernst equation *permeability of only one ion* -> theoretical number. For sodium, it is at 40 mv. In order for the action potential to go back up, all the sodium has to go back out and the potassium needs to balance out. Leak channel: has no control, always open. Potassium is the heavier player in action potential. Or have neurons connecting through the synapses -> positive current -> threshold. Voltage-gated sodium and potassium channels are located in the axon hillock. In a non-myelinated axon, there is passive propagation . In a myelinated axons where action potential can flow straight through bc of the channels. There are nodes of ranvier where the voltage-gated channels are sectioned off. Saltatory conduction: action potential is sectioned off in nodes, electrically passing.
