Question

A neuron has a resting membrane potential of -80 mV.

Opening:

One calcium channel causes a change in membrane potential of +5 mV.

One chloride channel causes a change in membrane potential of -3 mV.

When the post-synaptic neuron (above) is at resting potential, how many channels of which kind would need to open to generate an action potential?

Answer 1

A nerve impulse ( electrical signal) produced by the flow of ions across the plasma membrane of a neuron. It propagates along the surface of the membrane of a neuron. Propagation of nerve impulses in nerve cell (axon) changes the permeability of the membrane.This change in permeability causes a change in the potential across the axon. so this change in resting potential is called action potential. An action potential is generated when membrane is depolarized

there are two kinds of voltage-sensitive channels ,one selectively permeable to Na+ and the other to K + is responsible for changes in the permeability .Opening of voltage gated Na+ channels increase the permeability of membrane to Na+ ions .Na+ increases number of positive ions inside axon and K+ increases the positive ions outside the axon