<P> The central nervous system ( CNS ) is the part of the nervous system consisting of the brain and spinal cord . The central nervous system is so named because it integrates information it receives from , and coordinates and influences the activity of , all parts of the bodies of bilaterally symmetric animals -- that is , all multicellular animals except sponges and radially symmetric animals such as jellyfish -- and it contains the majority of the nervous system . Many consider the retina and the optic nerve ( cranial nerve II ) , as well as the olfactory nerves ( cranial nerve I ) and olfactory epithelium as parts of the CNS , synapsing directly on brain tissue without intermediate ganglia . As such , the olfactory epithelium is the only central nervous tissue in direct contact with the environment , which opens up for therapeutic treatments . The CNS is contained within the dorsal body cavity , with the brain housed in the cranial cavity and the spinal cord in the spinal canal . In vertebrates , the brain is protected by the skull , while the spinal cord is protected by the vertebrae . The brain and spinal cord are both enclosed in the meninges . In central nervous systems , the interneuronal space is filled with a large amount of supporting non-nervous cells called neuroglial cells . </P>
<P> The central nervous system ( CNS ) is the part of the nervous system consisting of the brain and spinal cord . The central nervous system is so named because it integrates information it receives from , and coordinates and influences the activity of , all parts of the bodies of bilaterally symmetric animals -- that is , all multicellular animals except sponges and radially symmetric animals such as jellyfish -- and it contains the majority of the nervous system . Many consider the retina and the optic nerve ( cranial nerve II ) , as well as the olfactory nerves ( cranial nerve I ) and olfactory epithelium as parts of the CNS , synapsing directly on brain tissue without intermediate ganglia . As such , the olfactory epithelium is the only central nervous tissue in direct contact with the environment , which opens up for therapeutic treatments . The CNS is contained within the dorsal body cavity , with the brain housed in the cranial cavity and the spinal cord in the spinal canal . In vertebrates , the brain is protected by the skull , while the spinal cord is protected by the vertebrae . The brain and spinal cord are both enclosed in the meninges . In central nervous systems , the interneuronal space is filled with a large amount of supporting non-nervous cells called neuroglial cells . </P>
name some components of the central nervous system ( cns )
name some components of the central nervous system ( cns )
brain spinal cord
brain spinal cord