Neurons keep a stable resting potential mainly by using special pathways and pumps. This resting potential, which is like a battery's stored energy, is about -70 mV. It's mostly decided by how ions are spread out inside and outside the neuron.

Let's break it down:

1. Ion Concentration:

   • Inside the neuron: There’s a lot of K+ (potassium) and not much Na+ (sodium) or Cl- (chloride).
   • Outside the neuron: There's a little K+ but a lot of Na+.

2. Ion Channels:

   • Potassium Channels: When the neuron is at resting potential, the K+ channels are mostly open. This lets K+ flow out of the cell, making the inside of the neuron more negative. About 90% of the resting potential comes from K+.
   • Sodium Channels: The Na+ channels are mostly closed when the neuron is at rest. However, there's a tiny bit of Na+ that sneaks in to balance the K+ that’s moving out.

3. Na+/K+ Pump:

   • This pump pushes out 3 Na+ ions while bringing in 2 K+ ions. This action helps create a more negative charge inside the neuron.
   • The pump works really fast, cycling around 100 times for each neuron every second. This is important for keeping the right balance of ions needed for the neuron to react to messages.

Thanks to the teamwork of ion channels and the Na+/K+ pump, neurons keep their resting potential. This helps them react to signals and send messages when needed.