Final answer:
The resting membrane potential in neurons is established by the action of the Na+/K+ ATPase pump, which actively transports ions across the cell membrane to maintain a negative charge inside the neuron.
Step-by-step explanation:
The resting membrane potential is established in neurons by the action of the Na+/K+ ATPase pump. This pump works to maintain the negative charge inside the cell by actively transporting three Na+ ions out of the cell and bringing two K+ ions in for every ATP molecule consumed.
As a result, the inside of the neuron boasts a higher concentration of K+ ions compared to the outside, and a higher concentration of Na+ ions on the outside relative to the inside. The greater permeability of the cell membrane to K+ compared to Na+ results in K+ ions moving out of the cell more easily than Na+ ions move in, thus maintaining a negative internal environment.
This concentration gradient and selective membrane permeability collectively contribute to the resting membrane potential, which is critical for neuron functionality, including the initiation and propagation of action potentials.