Myelinated neuron anatomy. Illustration of the structure of a nerve cell body (yellow, upper left) and its myelinated axon (right). Myelin (green) is an insulating material that is essential to increase the speed of propagation of the nerve impulse along the axon. Myelin arises from neuroglial cells, shown here with their nuclei (grey). The nerve cell body nucleus (grey) is also shown, along with dendrites branching out from the nerve cell. Dendrites bring signals to the nerve cell, while the axon transmits signals outwards. For this artwork with labels, see C023/8831.