2. The nervous system is an organ system incharge of sending
messages to body from the brain and spinal cord to all Parts of the
body.
• Coordinates, controls and integrates(unite) the different actions.
• Transmits signals between different parts of the body.
The Nervous System
3.
4. Tissue in the Nervous System
• Nerve Cell = Neurons
• Cell body with dendrites (receives messages).
• Axon insulted in myclin sheath (sends messages along viaaction potential).
• Glial Cells
• These are cells that protect and support the neurons.
5. Neurotransmitters
• These are chemical messengers that pass from neuron to neuron to
continue the message.
1. They are released into the synapse (space between neurons)
and picked up by the next neuron.
2. There are 200-300 chemicals in the body that serveas
neurotransmitters.
6. Nervous System
Nervous System consists of two main parts:
1. Central Nervous System (CNS)
2. Peripheral Nervous System (PNS)
7.
8. Central Nervous System
• Made up of brain and spinal cord.
• Acts as body's control
center,coordinates body's activities.
• Impulses travel through the
neuronsin your body to reach the
brain.
9. Peripheral Nervous System
• Made up of all the nerves that carry
messages to body from the central
nervous system.
• Similar to telephone wires that
connect all of our houses in the
community.
• Central Nervous System and
Peripheral Nervous System work
together to make rapid changes in
your body in response to stimuli.
10. The Brain
• Central Control of the body:-
-Divided into four parts
• Cerebrum
• Diencephalon
• Cerebellum
• Brain Stem
– The brain has 4 ventricles (fluid filled spaces)
• These are highly vascular and lined with cells that produce cerebrospinal
fluid. Maintains the blood-brain-barrier.
11. The Cerebrum
• This is the sophisticated, upper portion of
the brain.
- Covered in “grey matter” surface with wrinkles and
ridges called gyri and sulci.
- Divided into left and right hemispheres and into
lobes:-
• Frontal- personality, speech, logical reasoning
• Parietal- sensory reception and
spatialreasoning
• Occipital- Visual interpretation center.
• Temporal- Hearing and receptiveLanguage
• Limbic System- (deep in the brain)emotion,
short term memory,
Parietal-
12. Diencephalon
Located deep in the brain, more primitive in function.
--Divided into the Thalamus and hypothalamus.
• Autonomic nervous system.
• ControlRegulation of heart rate
• Regulation of body. temperatureBody
functions like hunger, sleep, thirst.
• Plays a role in emotions, home of the “gut
feeling“.
13. Cerebellum
This is the "Little Brain” located at the back ofthe
head below the occipital lobe.
• Has hemispheres just like cerebrum.
• Interior white matter called “Tree of life”.
• This part of the brain helps us coordinate
our movements and stay balanced.
14. Brain Stem
• Located at the base of the brain, most primitive
part.
Has three main parts:
• Pons- connects cerebrum to cerebellum and the
rest of the nervous system.
• Midbrain- contains reflex(automatic response)
regulation centers, plays role with sight and
hearing.
• Medulla Oblongata– vital functions such as heart
rate,blood pressure, respirations,vomiting, and
swallowing control.
15. Reflex Arch
• If a response, is reflexive, it means it is
automatic.
1. We do not have to think about it.
2. In fact, the action occurs before the brain
knows about it.
3. Regulated at the point where the spinal
nerve meets the spinal cord.
4. Automatic protective action.
5. Message reaches the brain later.
