Structure of neuron, cell body, axon, dendrites, synapses, synaptic button. The neuron is made up of several structures. The cell body in yellow has a pink nucleus and a nucleolus in its center. Outside the cell body are many dendrites. An axon starts from the cell body. It is surrounded by myelin sheaths in blue. It ends with many synapses. These synapses in contact with the dendrites and the cell body of another neuron form synaptic buttons. It is at the level of the synaptic buttons that the nerve impulse passes from one neuron to another.