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The middle or centre of the Earth is the core. However the middle of the layers from the surface to the centre of the Earth is known as mantle.
The nervous system is responsible for sending, receiving, and interpreting information from all parts of the body. The nervous system monitors and coordinates internal organ function and responds to changes in the external environment. (The role) The central nervous system consists of the brain and the spinal cord. It is part of the overall nervous system that also includes a complex network of neurons, known as the peripheral nervous system. (Central nervous system)