Final answer:
The membrane potential can be calculated using the Nernst equation. The resting membrane potential is typically around -70 mV, which is maintained by the sodium-potassium ATPase and leakage channels that manage the movement of Na+ and K+ ions across the cell membrane, resulting in a distribution of charge.
Step-by-step explanation:
Membrane potential may be calculated via the Nernst equation.
The resting membrane potential is usually around -70 mV in many cells and is critical for the function of cells, particularly neurons. The state at which this voltage is measured without any external influence is termed the resting membrane potential. Different ions, notably sodium (Na+) and potassium (K+), have gradients across the cell membrane that contribute to this potential.
The sodium-potassium ATPase (Na+/K+ pump) actively transports K+ ions into the cell and Na+ ions out of the cell, contributing to the membrane potential. Additionally, leakage channels allow for the passive movement of K+ and Na+ across the membrane. When K+ leaves the cell, it leaves behind a negative charge, contributing to the negative value of the resting membrane potential. The value for the resting membrane potential is expressed in millivolts (mV), and since the inside of a cell is more negative compared to the outside, it is signified by a minus sign, as in -70 mV.