× Didn't find what you were looking for? Ask a question
Top Posters
Since Sunday
5
o
5
4
m
4
b
4
x
4
a
4
l
4
t
4
S
4
m
3
s
3
New Topic  
Verrine Verrine
wrote...
Posts: 8
Rep: 0 0
8 years ago Edited: 8 years ago, Verrine
So I have been trying to understand the resting potential, but I just don't get it. All the information I have read so far tells me that the concentration of ions in the extracellular and intracellular fluid is largely balanced, which would make the system neutral, electrically speaking.
Even so, there exists this electric potential of the membrane, which is -70mV, meaning that the inside is more negative than the outside by 70mV.
I feel that these statements contradict.

Can anyone explain this to me? In simple terms if possible because I have tried to understand what is on wikipedia, but I didn't get it.
Read 438 times
2 Replies

Related Topics

Replies
wrote...
8 years ago
You have to know that there are equilibrium potentials of Na+ and K+ mainly. [K+] is more concentrated in cells than the environment, and [Na+] the contrary. So when the Na+ channels open because of a stimuli, Na+ enter to the cell following the chemical gradient and the membrane potential becomes more positive. Then K+ channels open, K+ go out of the cell and the membrane potential becomes negative again. But K+ channels are slower and more permeable than Na+ ones, that means that they allow more pass of K+ than the others. If more K+ go out of the cell than Na+ inside, the cell is more negative than the environment.



Verrine Author
wrote...
8 years ago
Ok, I understand what you are saying. The inside of the cell is more negative than the environment because there are more K+ going out than Na+ coming in... Then why is the membrane considered to be electrically neutral? 
New Topic      
Explore
Post your homework questions and get free online help from our incredible volunteers
  793 People Browsing
 110 Signed Up Today
Related Images
  
 75
  
 177
  
 73
Your Opinion
How often do you eat-out per week?
Votes: 79