The junction between an axon and its cell body; where action potentials are generated.
is the site at which the axon originates from the neuronal cell body, and is in continuity with the initial segment of the axon. This is the most excitable part of a neuron as a result of its high density of sodium channels and is therefore the site of initiation of the action potential
swelling at the cell body when axon begins. Then the axon maintains constant diameter down its entire length. The impulse is carried from the cell body toward the axon terminal to other cells (generally).