Why do ions flow from high concentration to low concentration?

[scilearner]

Hello everyone,

 

This a question related to ATP pump that uses electrochemical gradient to provide energy to make ATP. I have few questions about this.

 

1. In an electrochemical gradient there are more positively charged ions on one side of the membrane(In proton gradient case). So why do the protons move from highly concentrated area to low concentrated area? Is it because the side that has more protons repel each other and eventually push the protons away until the charge is neutralized?

2. If there is a higher concentration of ions in one area why do they move to the less concentrated area? Is it because higher concentrated area has higher pressure so they move to lower pressure area, because that side provides less impedance.

3. Now what exactly gives the energy for the ATP pump. Is it the movement of ions. Is it using the kinetic energy of the movement of ions across a gradient to produce ATP? If so why does it need a proton gradient, ions are moving all the time randomly even without gradient? Does the gradient give it a direction or something that can be efficiently utilized the pump.

 

Thanks a lot for anyone who is going to help. Thanks

[Bignose]

The random motion of the atoms and molecules ensures that if available, they will always spread out into an equilibrium configuration. And, in the absence of other forces, equilibrium is typically uniform distribution.

 

For example, you can put a drop of food coloring in a glass and let it sit. In time, the coloring will be evenly distributed over the entire glass. The drop, that was very concentrated in color, will eventually be spread out into and the entire glass will be a very pale color.

 

The molecules of the blue dye and moving in all random directions, and this randomness causes them to eventually fill the entire available volume evenly.