Its unit is Neuron
Largest cell of our body is neuron only.
Types: A. Central nervous system: Brain + spinal cord
B. Peripheral Nervous system : Nerves
C. Autonomic Nervous system: Sympathetic, Parasympathetic nervous system.
A. CENTRAL NERVOUS SYSTEM
Brain is covered by 3 layers Meninges
- Durameter (toughest)
- Arachnoid mater
Cerebrospinal fluid is filled between the meninges.
Grey matter controls activities such as speech, taste, smell, hearing (conscious activities)
Concerned with equilibrium of the body and brings about co-ordination and control of muscular activities of the body.
Lowest part of the brain and is connected to the spinal cord.
Controls the involuntary actions (respiration, heart beat, flow of blood in blood vessels, secretion of glands, etc)
First discovered by Marshal Hall.
Co-ordinated by spinal cord
First shown by Payloy on dog
It is controlled by the cerebrum
PERIPHERAL NERVOUS SYSTEM
Composed of Cranial nerves and spinal nerves.
Cranial are 12 pairs while spinal are 31 pairs.
Trigeminal : Mixed
Facial : Mixed
Vagus : Mixed(largest) AUTONOMOUS NERVOUS SYSTEM
Not under voluntary control.
Controlled by Central Nervous system.