Question

what factors determine the resting membrane poteintal ?? whats the importence of one of these factors for cell function?

Answer 1

ANSWER :-

Different types of ion channels are present on the neural membrane. These ion channels are selectively permeable to different ions. When a neuron is not conducting any impulse, i.e., resting, the axonal membrane is comparatively more permeable to potassium ions (K+) and nearly impermeable to sodium ions (Na+). Similarly, the membrane is impermeable to negatively charged proteins present in the axoplasm.Consequently, the axoplasm inside the axon contains high concentration of K+ and negatively charged proteins and low concentration of Na+. In contrast, the fluid outside the axon contains a low concentration of K+, ahigh concentration of Na+ and thus form a concentration gradient. These ionic gradients across the resting membrane are maintained by the active transport of ions by the sodium-potassium pump which transports 3Na+ outwards for 2 K+ into the cell. As a result, the outer surface of theaxonal membrane possesses a positive charge while its inner surface Structure of a neuron becomes negatively charged and therefore is polarised. The electricalpotential difference across the resting plasma membrane is called as the Resting membrane Potential.