Question

When a neuron is in resting state $i.e$ ., not conducting any impulse, the axonal membrane is

• A. Comparatively more permeable to $N{a}^{+}$ ions and nearly impermeable to $K^{+}$ ions
• B. equally permeable to both $N{a}^{+}$ and $K^{+}$ ions
• C. impermeable to both $N{a}^{+}$ and $K^{+}$ ions
• D. comparatively more permeable to $K^{+}$ ions and nearly impermeable to $N{a}^{+}$ ions

Answer 1

Answer: (D)

Whilst a neuron isn't conducting any impulse, i.E., resting, the axonal membrane is comparatively more permeable to potassium ions (k+) and almost impermeable to sodium ions (Na+). Similarly, the membrane is impermeable to negatively charge proteins present within the axoplasm. Consequently, the axoplasm within the axon contains high awareness of k+ and negatively charged proteins and coffee awareness of Na+. In comparison, the fluid outdoor the axon incorporates a low concentration of k+, high attention of Na+, and as a consequence form an attention gradient. Those ionic gradients across the resting membrane are maintained through the active transport of ions through the sodium-potassium pump which transports three Na+ outwards for two k+ into the cellular. As a result, the outer floor of the axonal membrane possesses an advantageous rate at the same time as its inner surface turns into negatively charged and therefore is polarised. The electric ability distinction throughout the resting plasma membrane is referred to as because of the resting ability.