<prompt> Uni directional flow of a nerve impulse is atSynapseAxonDendritesNode of Ranvier  <response>: In the nervous system, a synapse is a structure that permits a neuron or nerve cell to pass an electrical or chemical signal to another neuron or to the target effector cell. Ref: guyton and hall textbook of medical physiology 12 edition page number: 675,676,677 