NERVOUS SYSTEM, TYPES OF NEURON, TYPES OF NERVOUS SYSTEM, CENTRAL NERVOUS SYSTEM, PERIPHERAL NERVOUS SYSTEM

1. By:
Jitendra Bhangale
M.Pharm. DIPL
By the end of the lesson you should be able to
 Describe the transmission of impulses from senses
to central nervous system and back to muscles.
 Describe the reflex action and the pathway of the
reflex arc.
 Describe the function of reflex response.
 Describe the role of the central nervous system.
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2. nervous system
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3. sensory relay motor
neurone neurone neurone
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4. Carries impulses from receptors e.g pain
receptors in skin to the CNS( brain or spinal
cord)
Carries impulses from sensory nerves to
motor nerves.
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5. Carries impulses from CNS to effector e.g. muscle to
bring about movement or gland to bring about
secretion of hormone e.g ADH
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6.  Central Nervous System (CNS): brain and spinal cord
 Peripheral Nervous System (PNS): craniospinal
nerves
 Autonomic Nervous System (ANS): nerves that
control vital organs: heart, lungs, brain, etc.
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7. The Central Nervous System includes
White matter: bundles of axions and dendrites
Gray matter: masses of nerve cell bodies
The brain: inside the cranium
The spinal cord: inside the vertebral column
(the “backbone”)
envelop the entire CNS
(central nervous system)
dura mater The outer, hardest, toughest
arachnoid The middle, web like
pia mater The inner, thinner
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8. 8

9.  Cerebrum
 Cerebellum
 Diencephalon:- hypothalamus and thalamus
 Brainstem:- medulla oblongata, pons and
midbrain
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10. is divided into two cerebral hemispheres
has an outer surface,
or CORTEX,
made of “gray matter”
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11. 1. Left hemisphere:- controls the right side of the body
2. Right hemisphere: - controls the left side of the body
is divided into parts called lobes:
1. the frontal lobe
2. the parietal lobe
3. the temporal lobe
4. the occipital lobe
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12. is the center for voluntary movement
is called the “motor area” (movement)
includes the prefrontal area,
for intelligence, creativity, memory, and ideas.
Collects, recognizes, and organizes sensations:
feelings of
pain
Temperature
Touch
Position
movement
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13.  processes auditory (hearing) information
 stores auditory (hearing) and visual (seeing)
memories
is at the back of the cerebral hemisphere
involves
Vision
visual memory
eye movements
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14. coordinates muscle activity
has three parts:
the vermis
the right cerebellar
hemisphere
the left cerebellar
hemisphere
is located between the midbrain and the
cerebrum
has three parts:
the thalamus: receives sensory
information and sends it to the
cerebral cortex.
the epithalamus: contains the
pineal body and olfactory
centers.
the hypothalamus: connects the
endocrine and nervous systems.
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15. connects the endocrine and nervous systems.
controls
the autonomic nervous system
body temperature
carbohydrate and fat metabolism
appetite
emotions
w
 Pons: connects the medulla oblongata, the
cerebellum, and cerebrum
 Midbrain: contains auditory (hearing), visual
(sight), and muscle control centers.
 Medulla oblongata: lowest and most posterior
(at the back of the brain)
The hindbrain includes the pons and the medulla.
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16. Connects the medulla oblongata, cerebellum, and
cerebrum
Associates with sensory nerves: taste, hearing, and balance.
Controls muscles of the face.
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17. controls
alertness
heart action
respiration (breathing)
blood pressure
connects the CEREBRUM with the SPINAL
CORD
the RIGHT side of the brain controls the LEFT side of the body.
the LEFT side of the brain controls the RIGHT side of the body.
controls
Vision
Hearing
Muscles
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18.  A reflex is an action that:
occurs below the brain, within in the spinal cord
is an automatic reaction
is not conscious (voluntary)
can be inborn (a baby has it at birth, such as sucking,
swallowing, urinating)
can be learned (such as talking,walking, driving)
* An automatic reaction that happens without thinking about
it.
* A reflex happens quickly in less than a second.
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19.  INBORN  LEARNED
reading
knee jerk reflex typing
pupillary reflex swimming
swallowing dancing
coughing skating
blinking playing football
 knee jerk: lower leg jerks when knee is tapped
 Babinski: toes curl up when sole of foot is stroked
 pupillary: pupils of eyes contract in bright light
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20.  Continuation of the base of the brain
surrounded by vertebrae
 Covered by three protective membranes
(meninges)
 The spaces between the meninges are filled
with cerebrospinal fluid (CSF), which
cushion and protect the CNS
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21. 1. Center for many reflex actions
2. Provides means of communication
between the brain and the spinal
nerves
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22. - Consists of cell bodies and short
unmyelinated fibers
- H-shaped in a cross section
- Includes interneurons and portions of
sensory neurons and motor neurons
- Consists of bundles of myelinated long
fibers of interneurons (tracts)
- Connects the spinal to the brain
- Dorsally, contains ascending tracts taking
information to the brain
- Ventrally, contains descending tracts
carrying information from the brain
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23. - In humans, there are 12 pairs of cranial
nerves attached to the brain
- Include the vagus nerve which has
branches to the pharynx and larynx and
most of the internal organs
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24. - In humans, there are 31 pairs if spinal
nerves emerged from the spinal cord
- All spinal nerves are mixed nerves
conducting impulses to and from the
spinal cord
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25.  Includes all nerves that serve the internal
organs automatically and usually without
need for conscious intervention
 Divided into sympathetic and
parasympathetic systems
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26.  Nor epinephrine (NE) is neurotransmitter
 Preganglionic fibers arises from the
middle portion of the cord
 Accelerates heartbeat, dilates the bronchi,
increases the breathing rate
- Acetylcholine (ACh) is neurotransmitter
-
- Preganglionic fiber is longer than
postganglionic fiber
- Preganglionic fiber arises from the brain
and lower portion of the cord
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27. THANK YOU
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