PNB 2XB3 Lecture Notes - Lecture 3: Voltage-Gated Potassium Channel, Voltage-Gated Ion Channel, Theodor Schwann

• School: McMaster University
• Department: Psychology, Neuroscience & Behaviour
• Course: PNB 2XB3
• Professor: Dr. Daniel Goldreich

Document Summary

This is because all the voltage gated na+ channels have opened: 1. d) even if the cell were to become exclusively permeable to na+, vm would only just reach the. The leak k+ channels will always be open therefore you will never only be permeable to na+ (there will always be some k+ permeability). Vm can only reach the na+ iibm potential if the cell has 0 permeability to k+, which never happens. During, the ap vm never reaches ena because there is always some k+ permeability. Ions cannot flow through the membrane"s lipid bilayer. However, there are channels in the membrane which let the ions transport in and out: 2. Ap don"t come back on themselves because they have a refractory wake. They cannot keep going, and the rising phase cannot continue as the membrane encounters the inactivated na+ channels. The 2 ap will disappear when they meet, because each will encounter the refractory wake of the other: 3.