Question

What is the resting membrane of nerve fiber?

• A. +45 mV
• B. -70 mV
• C. -45 mV
• D. +75 mV

Answer 1

The correct option is B -70 mV

The resting membrane potential (RMP) is due to changes in membrane permeability for potassium, sodium, calcium, and chloride, which results from the movement of these ions across it. Once the membrane is polarized, it acquires a voltage, which is the difference of potentials between intra and extracellular spaces. Skeletal muscle cells: −95 mV, smooth muscle cells: −50 mV; astrocytes: −80/−90 mV, neurons: −70 mV; erythrocytes: −12 mV.