. central sensory and motor nerves running to and from the CNS 2. peripheral main interpretation and processing center 3. somatic controls voluntary responses 4. autonomic fight-or-flight responses 5. sympathetic relaxing responses 6. parasympathetic controls automatic responses

The human body is composed of the different systems or controlling parts, and among these organs the brain and spinal cord functions for the regulation of nerves and for the regulation of communication inside the human body. As, there are small basic units or cells called as neurons which makes up the basic framework for the functioning of this nervous system.

Now, each of our body's function is either voluntary or involuntary in nature. As, they arise to having a chemical imbalance or in other words a synapse inside the structure or body  of the neurons. While, all of the actions are full controlled by the central nervous system but some of them are controlled by the processing system which are called as the voluntary changes or actions. And on the other those which are not controlled all by the human body, as such actions are said to be involuntary in nature.  While, the nervous system outside the more organized and becomes more complex when we analyze the nervous system outside the CNS  and such neural system is then termed as the peripheral nervous system.Some of the response are quick and do not require any longer for the body to react in and such body responses are termed as the autonomic fight-or-flight responses. As, such functions or changes inside the body posture and system included inside the sympathetic relaxing responses.

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