What is concentrated outside the cell when a nerve is in its resting state?

In a nerve cell at rest, the distribution of ions across the cell membrane plays a critical role in its electrical activity. During the resting state, potassium ions (K+) are primarily concentrated inside the cell, while sodium ions (Na+) are concentrated outside the cell. This results in a resting membrane potential that is typically around -70 millivolts, where the inside of the cell is more negative compared to the outside.

When the nerve is at rest, sodium ions and chloride ions are both more concentrated outside the cell, while potassium ions are more concentrated within the cell. Thus, the concentration of sodium ions outside is the key factor that contributes to the depolarization of the nerve cell when it is stimulated.

Understanding the distribution of these ions is essential for comprehending how action potentials are generated and propagated in nerve cells. The resting state is crucial for allowing the nerve to respond properly to stimuli, and it is this ionic balance that sets the stage for the transmission of nerve impulses.

The correct answer focuses on the positive contribution of sodium ions, which are vital in establishing the cell's resting potential and its readiness to generate an action potential when required.