Quick Answer. Voltaire wrote Candide as a satire of the then-prevalent philosophical optimism advanced by Gottfried Wilhelm Leibniz. Voltaire, moved by contemporary events like the Seven Years' War and the 1755 Lisbon earthquake, felt that optimism was a naive way of viewing the world.
Neurons carry impulses from one place to another, around the many parts of the nervous system. They connect receptors to the central nervous system and also connect one part of the nervous system to another, for example in the brain and spinal cord.
A nerve is a bundle of axons. A sensory neuron is a nerve cell that transmits impulses from a sense receptor such as those in the eye or ear to the brain or spinal cord. A motor neuron is a nerve cell that transmits impulses from the brain or spinal cord to a muscle or gland.A relay neuron connects sensory and motor neurons and is found in the brain or spinal cord (see diagrams 14.1 and 14.2).iagram 14.1 - A motor neuron. The cell body of neurons is usually located in the brain or spinal cord while the axon extends the whole distance to the organ that it supplies. The neuron carrying impulses from the spinal cord to the hind leg or tail of a horse, for example, can be several feet long.