membrane potential

biology

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June 30, 2026

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The membrane potential refers to the imbalance of electrical charge across the cell membrane of electrically excitable cells, like neurons. This potential typically ranges from -60 to -95 millivolts, with the inside of the cell being more negative than the outside.1

This electrical difference is maintained by the sodium-potassium pump, which actively transports sodium ions out of the cell and potassium ions into the cell, using energy from ATP. The semipermeable nature of the cell membrane, allowing certain ions to pass more easily than others, also contributes to establishing and maintaining this potential. Changes in membrane potential, such as depolarization and hyperpolarization, are crucial for processes like nerve impulse transmission.2341

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nervous system
The neuronal membrane
…neurons this potential, called the membrane potential, is between −60 and −75 millivolts (mV; or thousandths of a volt; the minus sign indicates that the inner surface is negative). When the inside of the plasma membrane has a negative charge compared to the outside, the neuron is said to be…
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…neurons this potential, called the membrane potential, is between −60 and −75 millivolts (mV; or thousandths of a volt; the minus sign indicates that the inner surface is negative). When the inside of the plasma membrane has a negative charge compared to the outside, the neuron is said to be…
Read More