Transcript Neurons_PowerPointsx

Neurons
By: Annette Miles
Messages, in the form of electrical
impulses, constantly travel back and forth
between the brain and other parts of the
body.
A special cell called a neuron is
responsible for carrying these messages.
There are about 100 billion neurons in the
human brain.
A neuron has
three main
parts. The
cell body
contains the
nucleus and
directs all
activities of
the neuron.
Label, color, and
describe the cell
body…(yellow)
and the nucleus
… (green)!
(The cell body or soma
contains the nucleus)
Dendrites
extend out
from the cell
body like
branches and
receive
messages from
other nerve
cells.
Label and
describe the
job of the
dendrites.
(Receives Messages)
An axon is a long
single fiber that
transmits messages
from the cell body to
the dendrites of
other neurons or to
other body tissues,
such as muscles.
Label, color,
and describe
the job of the
axon…(orange)
(Transfers Message)
A protective covering
called the myelin
sheath, covers most
neurons. Myelin
insulates the axon and
helps nerve signals
travel faster and
farther.
Label, color
and describe
the job of the
myelin
sheath…(blue)!
(Protects and helps messages
send faster and farther)
Messages travel along a single neuron as
electrical impulses, but messages between
neurons travel differently.
The transfer of information from neuron to
neuron takes place through the release of
chemical substances into the space between
the axon and the dendrites.
These chemicals are called neurotransmitters,
and the process is called neurotransmission.
The space between the axon and the
dendrites is called the synapse.
Label, color,
and describe
the axon
terminals…
(red)!
(Sends Neurotransmitters)
When neurons
communicate, an
electrical impulse
triggers the release of
neurotransmitters from
the axon into the
synapse. The
neurotransmitters cross
the synapse and bind to
special molecules on
the other side, called
receptors. Receptors are
located on the
dendrites. Receptors
receive and process the
message.
Axon terminal
What is ????
Axon terminal
What is ????
Axon terminal
What is ????
Axon terminal
What is ????
Axon terminal
What is ????
Axon terminal
What is ????
Review
myelin sheath protects the axon and helps
1. The __________________
messages travel faster.
dendrites
2. The __________________
receives messages from
other neurons.
cell body
3. The __________________
contains the nucleus and
directs the activities of the cells.
4. Messages travel through a space called the
synapse
__________________
between neurons.
Extension:
Make a pipe cleaner model of a
neuron.
RESOURCES
http://images.google.com/imgres?imgurl=http://www.drugabuse.gov/JSP/MOD3/images/NEUR
ON2.gif&imgrefurl=http://www.drugabuse.gov/JSP/MOD3/page3.html&usg=__rzbUKVLZVJ0FmcIhJ4b9t_lA4k=&h=350&w=350&sz=9&hl=en&start=16&tbnid=T_maaMtqaqiAM:&tbnh=120&tbnw=120&prev=/images%3Fq%3Dneuron%26gbv%3D2%26hl%3
Den%26sa%3DX
http://www.biotechlearn.org.nz/var/biotechlearn/storage/images/focus_stories/transgeni
c_cows/images/a_nerve_cell/219060-1-eng-AU/a_nerve_cell_large.jpg
http://upload.wikimedia.org/wikipedia/commons/thumb/b/bc/Neuron_Handtuned.svg/400px-Neuron_Hand-tuned.svg.png