Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
7 Cards in this Set
- Front
- Back
|
Vm is a product of Charge Separation
|
-Selective permeability of the membrane at rest
-K+ channels are leaky -Na+ channels are closed at rest -Large molecules cannot pass |
|
|
Very few ions are involved in establishing the Vm
|
- only about 6 ions are responsible for generation a -90 mV membrane potential on a small patch of membrane
-bulk solution has no effect |
|
|
Vm is determined by 2 Factors
|
-Active Transport
-Passive Diffusion -Na-K pump essential to maintain gradient |
|
|
Donnan Equilibrium
|
-The high concentration of A- inside the cell drives out Cl- and causes a sharp Cl- gradient
|
|
|
Nernst Potential
|
-Calculates the electrical potential of an ion across a membrane at equilibrium
-helps determine which ions are primarily responsible for the value of the Vm -K+ primarily responsible for determining Vm |
|
|
The Goldman Equation
|
-Describes the relative contribution of multiple ions on the resting membrane potential based on difference in ion permeability
|
|
|
Action Potentials
|
-All or nothing
-At rest: only leaky K+ channels are open -Rising Phase: Na+ channels are open -Falling Phase: Na+ channels inactivate and voltage gated K+ channels open -Recovery Phase: Na+ channels are closed and voltage sensitive K+ open |
