All information from our environment is detected by the specialised tips of some Nerve cells. These receptors are usually located in our sense organs such as the inner ear, the nose ,the tongue and so on. So gustatory receptors will detect taste while olfactory receptors will detect smell. This information acquired at the end of the tip of a nerve cell that creates an electrical impulse. This impulse travels from that dendrite to the cell body and then along the Axon to its end. At the end of the electron the electrical impulse sets off the release of some Chemicals. These Chemicals cross the gap, or synapse, and start a similar electrical impulse in a dendrite of the next neurone. These neurons are connected to the brain where all this information is processed. And then the processed or result travels through the muscles and performed by the organs. The working goes like Recepters->sensory neuron->brain->motor neuron->effectors. It all depends on the neurons. Neurons are present in all parts of the body so they are never fiber is connected all together in the spinal cord which is connected direct with brain.