Download Nervous System II – Neurons

Name:
Date:
SciTec 3
Nervous System II – Neurons
Neurons
Information is transmitted through
which is made up of
 Also called
 We have about
neurons in our bodies!
What do they do?
o
and
information
What makes them special?
1. Can be
a. Reacts to a stimulus and changes it into an electrical signal (nerve impulse)
2. They are
a. Transmits nerve impulse from one neuron to another
3. Consume lots of
and
a. Would only survive a few minutes without oxygen
4. Can live more than
years
a. You get one set of neurons and that’s it! You keep them your entire life.
5. Cannot
a. They cannot be replaced if destroyed!
1
Name:
Date:
SciTec 3
What do they look like?
(Whole fibre)
2
Name:
Date:
SciTec 3
Parts of the Neuron
Structure
Dendrites
Soma
Nucleus
Axon
Schwann
Cells
Myelin
sheath
Nodes of
Ranvier
Axon
terminal
Description and Function
The branched projections of the neuron.
____________ and ____________ electrochemical signals from
other neurons .
The bulbous end of a neuron.
 The cell “body”
Contains the ____________________.
Contains the genetic material of the cell.
Controls the cell’s ____________________.
The nerve fibre.
________________ electrical impulses way from the soma
 ___________________ information
Glial cells
 Non-neuronal cells; the glue of the nervous system
Form the ________________________.
Fatty layer formed around the ______________ of a neuron.
Helps ______________ the speed at which impulses propagate
along the axon because the impulses can hop between the
_______________________________.
__________________ in myelin sheath.
Allow for ____________________ across the cell membrane which
propagates the electrical impulses.
The _______________________ projects of the neuron.
Releases __________________________________ to next neuron.
3
Name:
Date:
SciTec 3
Sending a Signal
• Signals are sent via
•
Travels from neuron to neuron until reaches target
•
Always
•
receive the message or
transform them into electrical nerve impulses
•
•
to
and
Created by K+ and Na- ion movement
Travel from one neuron to another via
•
These are chemical substances secreted by the axon terminal that travel
across the transmission zone between neurons to the next dendrite
 Transmission zone is called a
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