The nervous system coordinates the body's behavior and transmits signals through neurons. The nervous system is composed of the central nervous system, made up of the brain and spinal cord, and the peripheral nervous system, consisting of nerves that connect to sensory organs and internal organs. Nerve cells called neurons are the basic functional units and transmit electrical or chemical signals through axons and dendrites to regulate bodily functions.

2. The nervous system
The nervous system is the part of an animal's body that coordinates its
behavior and transmits signals between different body areas.
The various nervous system of the body are control by the nervous
system. Nerve cell: Nerve cell is the structural and functional unit of the
nervous system. Thenerve cell or neurons is essential for:
1. Regulation
2. Controll ed
3. Co-ordination of body function.

3. The neuron consist
1. Cell body: The nerve cell body contains nucleus and cytoplasm.
2. Axon: It takes impulse away from the body of the cell. The axon is
covered by myelin sheath. Neurilomma is another covering
membrane of the myelin sheath. Schewan's cell is present within
the myelin sheath.
3. Dendrites: It takes impulse in to the body. The space where the nerve
impulse jumps from one neuron to another is called the Synapse. The
transfer of the impulse across the synapse depends upon the release
of a chemical substance called Neurotransmitter
(Acetylcoline,epinephrine and dopamine are example of
Neurotransmitter )

4. External Resepta: Sensory organ (ear, nose, eye, skin, tongue)
Internal Resepta: Muscle, Blood vessels, Glands
Sensory nerve: The peripheral nerve that carries impulse the external resepta to
the spinal cord and brain is called afferent (sensory) nerve (Impulses towards
the brain.
Motor nerve: The Impulses carry from the CNS to organs that produce response
is called Efferent (Motor) nerve. Brain to muscle (internal resepta)
Mixed Nerve: It carries both sensory and motor nerve fiber

5. Nervous
System
Central Nervous
system
Brain
sympathetic
nerves
Spinal cord
Parasympathic
nerves
Autonomic
nerves
12 pairs of
Cranial nerves
Peripheral
Nervous system
31 pairs of
Spinal nerves

6. Cranial nerves : OOOTTA FAG VAH
No Cranial Nerve Function
1 Olfactory (Sensory) Smell
2 Optic (Sensory) Vision
3 Oculomotor (Motor) Eye movement
4 Trochlear (Motor) Eye movement
5 Trigeminal (Sensory) Facial movement
6 Abducens (Motor) Eye movement
7 Facial Nerve (Mixed) Taste buds (anterior part of
Pharynx
8 Acoustic (Sensory) Hearing and equilibrium
9 Glossopharyngeal (Mixed) Posterior part of Pharynx
10 Vagus (Mixed) Muscle of swallowing
11 Accessory (Motor) Neck and Back
12 Hypoglossal (Motor) Tongue movement

7. Sympathetic:
Stimulate the body during stress and emergency it increase B.P, Heart beat and
Respiratory nerve.
Parasympathetic: Normally act as a balance for the sympathetic nerve (B.P,
heartbeat rate, respiration it will be decrease.
Brain: Brain is the highest co-coordinating integrating center of central nervous
system. The brain lies within the cranial cavity of the skull. The brains consist of
gray and white metter.
 The gray matter containing cells bodies and dendrites of peripheral nerves.
 The White matter containing the nerve fiber tracts with myelin sheaths.
 The layers are give protection to the brain and spinal Cord.

8. Outer Layer Dura Matter
Middle Layer Arachnoid Matter
Inner Layer Pia Matter

9. Space between arachnoids and Pia metter is called subarachnoid space
which filled with CSF (Cerebral spinal fluid).The CSF is clear, colorless
fluid it contains protein, sugar, chloride, lymphocytes.
It gives protection to the brain and spinal cord.
• The largest part of the brain is the cerebrum. The outer nervous tissue
of the cerebrum known as the Cerebral cortex is arranged in folds to
form elevated portions known as Convolutions (Sulci) and the elevated
parts between the sulci is called Gyri.
 The cerebral cortex divided in to four lobes
1. Frontal 2.Pariental
3. Temporal 4. Occipital
Functions of the four lobes:
Frontal Pariental Temporal Occipital
Judgment Writing Speech Vision
Memory Hearing Smell
Intelligence
Thinkink

10. Part of the brain Functions
Cerebrum Thinking,Reasoning,Sensation,Movement,Mem
ory
Thalamus Relay station for body sensation pain
Hypothalamus Body temperature,Sleep,Appetite
,Emotions,control of the Pituitary gland.
Cerebellum Co-ordination of voluntary movements
Pons Connection of nerve fiber tracts.
Spinal Cord The spinal cord contains 31 pair of Spinal nerve.
The Spinal cord is a column of nervous tissue
extending From the medulla oblongata to the
second lumbar vertebra within the vertebral
column. It ends as the cauda
equina (horse's tail)
Functions of the parts of the brain :