nervous system

1. Organization of nervous
system ,neuron, neuroglia,
classification and properties
of nerve fibre

2. Nervous system
PERIPHERAL NS
AUTONOMIC NS
SYMPATHETIC NS PARASYMPATHETIC
SOMATIC NS
CENTRAL NS
BRAIN
FORE BRAIN
TELENCEPHALON
Cerebral cortex ,
Basal ganglia,
hippocampus,
amygdala
DIENCEPHALON
Thalamus,
hypothalamus
MIDBRAIN
MESENCEPHLON
Tectum ,
Tegmentum
HINDBRAIN
METENCEPHLON
Pons, cerebellum
MYELENCEPHALON
Medulla
SPINAL CORD

3. CNS: SPINAL CORD
FUNCTION
• Conducts afferent
stimuli from sensory
receptor to brain.
• Conduct efferent
stimuli from brain to
effectors/muscles.
• Site of reflex
integration and house
certain central
pattern.

4. CNS: BRAIN
BRAIN

5. CNS PROTECTION
Against physical damage
Skull/vertebrae
-Hard external protection
Against chemical damage
Blood brain barrier
-Tight junctions form physical
barrier across capillaries
BOTH
Cerebrospinal fluid
-Shock absorption
-Stable ionic composition
Meninges
-Pia mater (Innermost layer)
-Arachnoid mater
-Dura mater

6. Neurons (also called
neurones or nerve
cells) are the
fundamental units of
the brain and nervous
system, the cells
responsible for
receiving sensory input
from the external
world, for sending
motor commands to
our muscles, and for
transforming and
relaying the electrical
signals at every step in
between.
NEURONS

7. NEUROGANLIA
Regulate neuron environment &
form the myelin sheath around
neurons
 Astrocytes: Regulate neuron
environment
 Oligodendrocyte: Form myelin
sheath in CNS
 Schwann cell: Form myelin sheath in
PNS
 Ependymal cells : line the ventricles,
synthesize CSF
 Microglia: Monocytes of the brain

8. Classification of neuron

9. Properties of Nerve fiber
Excitability
Conductivity
Unfatigability
Refractory period
All-or-none Law
Summation
accommodation

10. THANK YOU