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Neural network. Computer illustration of a network of nerve cells (neurons). Neurons are responsible for passing information around the central nervous system (CNS) and from the CNS to the rest of the body. Each nerve cell consists of a nerve fibre (axon, long) leading to a nerve cell body (lumps) surrounded by numerous extensions called dendrites (long, thin). Dendrites collect information from other nerve cells or from sensory cells and pass them to the cell body. The nerve impulse is then sent along the axon to another nerve. (KEYSTONE/SCIENCE PHOTO LIBRARY/MAURIZIO DE ANGELIS/SCIENCE PHOTO LIBRARY)