The nerve impulse

Hydrolysis of ATP provides energy that is used to pump out 3 s ions + pump in 2 p ions into the axon of a neurone through a specific cation pump by AT A reduction of the membrane permeability to s ions maintains a resting potential of -70mV on the inside of the axon. Generation of an action potential also uses the charges from ions. S gated channels open in the axon membrane allowing s ions to enter. This causes the membrane to depolarise until the threshold voltage of +40mV opens p gated channels. This causes p ions to leave repolarising, and eventually hyperpolarising the cell. This wave of depolarisation caused by these ion movements allows the passage of nerve impulse and coordination of the animal within its environment