What constitutes the central and peripheral nervous system ? How are the components of central nervous system protected ?

Explanation

Central Nervous System : It is hollowed part of nervous system that lies along the mid - dorsal part of the body. It has two parts-brain and spinal cord.
Peripheral Nervous System : It is solid lateral part of nervous system that develops from CNS and connects defferent parts of the body with CNS.
Peripheral nervous system has two components :
Voluntary and Involuntary - Voluntary peripheral nervous 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. Involuntary peripheral nervous system is also called autonomic nervous system. It has two parts- sympathetic and parasympathetic.
The control the functioning of various internal bady parts.
Protection of brain : Cranium.
Protection of spinal cord : Vertabral column.