The central nervous system or CNS receives the sensory information from all parts of the body, integrates it and responds accordingly. The central nervous system consists of two main organs: the spinal cord and brain. The spinal cord is responsible for bringing the sensory information from various parts of the body to the brain and relaying the motor information from the brain to various parts of the body. The brain integrates the sensory inputs from the body and makes decisions and passes them on to the body. Conscious and subconscious actions are all controlled by this system, such as thinking, sleeping, eating, running, etc. The central nervous system is critical to our survival and hence is protected by bones. The spinal cord resides in vertebrae and the brain is protected by the cranium.

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