Nerve impulses travel along the long cellular extension of the neuron called the

Dendrites

Explanation: Dendrites are branched extensions of a nerve cell that sends the electrochemical stimulation/information received from other nerve cells to the cell body of the neuron from which the dendrites emanate. In other words, they are part of the neuron that receive stimulation for the cell to become active.

an active site is a region that is present on an enzyme where the reactants or the substrate molecules we can say bind and experience a chemical reaction. the substrate is basically a reactant whose concentration is changing and that is converting into a product after binding at the active site of an enzyme