How does the spinal cord help in the function of the central nervous system?

The central nervous system or CNS controls various functions of our body. These include, but are not limited to, motion, metabolism, sleep, and sensory perceptions. The CNS is composed of two parts: the brain and the spinal cord. The brain is similar to the central processing unit of a computer (just much more powerful than a computer). The brain receives various sensory inputs from different body parts, processes them, analyzes them and instructs the particular body organ on what to do. The spinal cord connects the brain and the rest of the body. Our spinal cord is contains bundles of nerve fibers and depending on their information transfer direction, they are classified as ascending tracts and descending tracts. The former transfers information from various body parts to the brain, while the latter transfers information from our brain to the various parts of the body. Thus, the spinal cord enables information transfer between the rest of the body and the brain and along with the brain makes up the central nervous system.

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