Electrochemical Equilibria

Question 1

What are the 3 things that establish electrochemical gradients?

Answer 1

1. The pump moves ions against their concentration gradients
2. There is restricted ion movement through channels
3. The membrane store ionic charges on its inner and other surface (capacitance)

Question 2

Sometimes when ions move through the membrane they split, where does this energy come from?

Answer 2

The membrane pump

Question 3

What work opposes the osmotic work?

Answer 3

The electrical work

Question 4

What happens when the osmotic force is called the equilibrium potential?

Answer 4

The force of the concentration gradient pushing an ion out the cell is equal to the force pushing the ion in. Electrical work is equal to osmotic work at equilibrium.

Question 5

What are the units for the Nernst equation?

Answer 5

Joules per coulomb (volts)