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Psychology 3600 Action Potential Saltatory Conduction Ion Channels Membrane Currents. Myelinated Axon. Saltatory Conduction. AP Propagation/ Saltatory Conduction. http://www.blackwellscience.com/matthews/actionp.html. AP Properties. 1. Threshold 2. All-or-none 3. Frequency coding
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Psychology 3600 Action Potential Saltatory Conduction Ion Channels Membrane Currents
AP Propagation/ Saltatory Conduction http://www.blackwellscience.com/matthews/actionp.html
AP Properties 1. Threshold 2. All-or-none 3. Frequency coding 4. Passive spread
EK Equilibrium membrane potential for potassium is -75 to -100mV.
ENa Equilibrium membrane potential for sodium is +40 to +60mV.
Action Potential Boundaries ENa EK
An action potential is a rapid change from a potassium dominated potential to a sodium dominated potential and back.
Ion Channel Criteria Single channel conductance Ion selectivity Gating Pharmacology
Ion Channel Criteria Single channel conductance Ion selectivity Gating Pharmacology
Hydrated Ions The larger the unhydrated ion in size, the more dispersed is its own charge and the less strongly it will attract water. This leads to the incongruous situation of the larger the ion, the less hydrated it is, and the smaller the relative size of the hydrated whole. Thus, K+ > Na+, but hydrated K+ < hydrated Na+.