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Flashcards in Resting Potential Deck (12):
1

What is the membrane voltage equation?

V=Q/C

2

How is depolarization achieved?

-Reduction in charge separation
-Less negative membrane potential

3

How is hyperpolarization achieved?

-Increase in charge separation
-More negative membrane potential

4

Which establishes ionic gradients - Ion pumps or ion channels?

Ion pumps ! active transporters which establish ionic gradients

5

Where are the following ions in higher concentration - outside or inside the cell?
1. K+
2. Na+
3. Ca2+

1. K+ is higher inside
2. Na+ is higher outside
3. Ca2+ is MUCH higher outside

6

Is the direction of current flow defined as the direction of net movement of Positive or Negative charge?

POSITIVE

7

What is the nernst equation?

E=RT/zF Log (X)2/(X)1

or just know:
E=61.5 Log (Koutside/Kinside)

8

What is the nernst equation used for ?

To calculate equilibrium potential (theoretical situation mostly)

9

What is the goldmans equation used for?

To calculate a steady state potential --> membrane potential (accounts for permeabilitites)

10

What is the Pna/Pk ratio or alpha of the goldman equation?

alpha =0.05

11

What is a result of interstitial hypokalemia (lower K+ concentration)

Cellular hyperpolarization (more negative)

12

What is the result of intersitial hyperkalemia (higher K+ concentration)?

Cellular depolarization (more positive)