NEETZoologyNeural Control and Coordination
What is the resting potential of the neuron?
Options
- APositive charge on the inner surface of the axonal membrane.
- BNegative charge on the inner surface of the axonal membrane.
- CPositive charge on the outer surface of the axonal membrane.
- DNegative charge on the outer surface of the axonal membrane.
Correct answer
B. Negative charge on the inner surface of the axonal membrane.
Step-by-step solution
Neurons are excitable cells because their membranes are in a polarised state, meaning the electrical potential difference across the membrane is maintained by ionic gradients. When a neuron is resting, the axonal membrane is more permeable to potassium ions (K⁺) and nearly impermeable to sodium ions (Na⁺). The axoplasm inside the axon contains high concentration of K⁺ and low concentration of Na⁺. The resting potential of the plasma membrane of a neuron is the electrical potential difference across the resting plas