Download Nervous System

Nervous System
Function of the nervous
system
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Transmits stimuli to the brain
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(sound, sight, taste, smell, feel)
Processes information (thinks)
Responds to stimuli
Body’s communication system
Controls/regulates other body systems
Maintains homeostasis.
Structures of the nervous system
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Brain
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Spinal cord
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Mass of neurons
“grey matter”
Connects CNS to PNS
Neuron
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Aka nerve cell
Nervous systems
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CNS
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Central nervous
system
Brain
Spinal cord
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Controls body
systems
Regulates
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Heart rate
Breathing etc.
Nervous systems
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PNS
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Peripheral nervous
system
All of the nerves
outside of the CNS.
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Controlling voluntary
systems. ie:
Nerves of the
extremities.
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Arms
Legs
Etc.
Nervous systems
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ANS
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Autonomic nervous
system
Special peripheral
nerves that work
automatically.
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Control involuntary
processes. ie:
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Heart beat
Digestion
Blinking
Saliva production
Neuron
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Nerve cell
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2 types
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Sends stimuli away
from brain to muscle
Soma
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Sends stimuli towards
the brain spinal cord
Receive the signal /
impulse
Sends signal / impulse
towards the cell body
Efferent aka motor
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Dendrites
Afferent aka sensory
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Body of the cell
Contains the nucleus
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Axon
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Sends signal /impulse
away from cell body
Towards the synapse
Attaches to muscle
synapse
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The gap / space
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Between neurons.
Impulses jump from
the axon
Across the synapse
To the dendrite of
the next neuron
Neuron
Myelin Sheath
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Protects nerves of
the PNS.
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Beads of myelin
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Made of Schwann
cells
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Creates ‘white’
appearance
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“white matter”
Reflex Arc
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Stimuli / impulse is
sent to spinal cord /
brain
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Signal / impulse is
sent to muscle.
Conclusion
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Understanding nerves and how they
work are very important.
They relate to pain and numbness in
the dental field.
You are looked at as the expert, you
should know a little more than your
patients.
Any questions?