Central nervous system

Brain and spinal cord

The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain, and the spinal cord. The retina is also technically part of the CNS. The CNS is named so because the brain integrates the received information and coordinates and influences the activity of all parts of the bodies of bilaterally symmetric and triploblastic animals—that is, all multicellular animals except sponges and diploblasts. It is a structure composed of nervous tissue positioned along the rostral (nose end) to caudal (tail end) axis of the body and may have an enlarged section at the rostral end which is a brain.

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