Human Nervous System is furthur divided Perpheral Nervous System (PNS) and Central Nervous System (CNS). You have to write about the structure of CNS.
CNS is made up of two components:

• Spinal Cord
• Brain

The spinal cord:

• conducts sensory information from the peripheral nervous system (both somatic and autonomic) to the brain
• conducts motor information from the brain to our various effectors like:

skeletal muscles
cardiac muscle
smooth muscle
glands

• serves as a minor reflex center

The brain:

• receives sensory input from the spinal cord as well as from its own nerves (e.g., olfactory and optic nerves)
• devotes most of its volume (and computational power) to processing its various sensory inputs and initiating appropriate — and coordinated — motor outputs.

The Brain can be divided into three parts:

• forebrain (also known as the prosencephalon — shown in light color)
• midbrain (mesencephalon — gray)
• hindbrain (rhombencephalon — dark color)

Now you have to furthur explain these parts...


Here are the links for reference:

http://www.dls.ym.edu.tw/chudler/nsdivide.html
The Central Nervous System

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