What constitutes the central and

Central Nervous System (CNS): It is hollowed part of nervous system that lies along the mid-dorsal part of the body. It has two parts, brain

(located in the head) and spinal cord (located in the trunk).

Peripheral Nervous System (PNS): It is soild lateral part of nervous system that develops from CNS and connects different parts of the body

with CNS. Peripheral nervous system has two components, voluntary and involuntary. Voluntary peripheral nerous system is under the control of

will. It consists of cranial nerves from brain and spinal nerves from spinal cord. Involuntary peripheral nervous system works independent of will. It

develops from some cranial and spinal nerves. Involuntary peripheral nervous system is also called autonomic nervous system. It has two parts,

sympathetic (for emergency) and parasympathetic (for moderation). They control the functioning of various internal body parts.

Protection of Brain: Brain box or Cranium, meninges and cerebrospinal fluid.

Protection of Spinal Cord: Vertebral Column, meninges and cerebrospinal fluid.