Download Nervous System ppt

4/6/16
Homework share-out: Feedback Loops!
Date:
4/6/16
Topic:
Nervous System
Page # ___
Date:
4/6/16
Topic:
Nervous System
Page # ___
Today in Room 326/311…
HW: Paragraph using vocab on how a signal is passed through the
body
CONTENT OBJ: SW describe the structure and function of a
neuron
LANG. OBJ: SW verbally identify the parts of their candy neuron
AGENDA:
AS: What do you know about brain cells? (5 min)
Neuron Structure/Function (10 min)
Signaling Activity (10 min)
Candy Neurons (15 min)
Neurons and Muscle Contraction (15 min)
Muscle Workout Activity (5 min)
What makes muscles grow? (5 min)
Signaling*
Two types of cells
Neurons = produce, send, and receive signals
Glial cells = protect, support, and insulate neurons
JOURNALS OUT!!
Neurons*
What’s a neuron?
Nerve cell: A specialized cell that transmits nerve
impulses
Example?
Run throughout our body
Send signals to each other
Relay messages to the
brain
Neuron Fun Facts
Average # of neurons in the brain
= 100 billion
Rate of neuron growth during
fetal development =
250,000 neurons/minute
Neuron width is thinner than a
human hair
Speed of signal transmitted through
a neuron = 250 miles/hour
All your neurons lined end to end
would span about 600 miles
Neuron Structure
Why are telephone wires coated in plastic or
rubber? Same with TV cords, cell phone
chargers, etc.?
The rubber insulates the electric
signal!
Allows
message
to be
carried
Neuron Structure
Neurons in the brain work the same way!
The carry electric signals to and from the brain,
so they need insulation to successfully carry the
signal wherever it needs to go
Head to tail orientation
Neurons connect
to each other*
k
Action potential =
peak of electrical impulse
(must be reached to transmit signal)
Signaling Timed Trial
Line up side-by-side while sitting in the floor
You should be shoulder-to-shoulder with the person
next to you
Gently hold the forearm of the person to your right
We are going to send a “squeeze” signal through the
class. The first person will gently squeeze the second
person, etc. When you feel a squeeze, squeeze your
partner. I will time how long it takes the signal to
reach the last person.
Arm Touch Avg. Time:
Leg Touch Avg. Time:
Time Trials
Scenario 1: Arm Touch
Scenario 2: Leg Touch
Time (seconds)
Time (seconds)
Trial 1
Trial 1
Trial 2
Trial 2
Trial 3
Trial 3
Results
Comparing the results, what would you say about each
situation? Why is this the case?
Some signals are transmitted through a series of
connected neurons, and some signals are transmitted
through a really long neuron (long axon)
Which animal would you think would need really long
axons to transmit signals throughout the body?
Fun Fact: Length of giraffe primary axon
(head to toe) = 15 feet
Neuron Structure*
Today we will use
candy to create
a neuron that has all
necessary
components!
All candies should
be used. But it’s up
to you how to do it!
Hint: The red vines
are hollow!
Draw
Materials (per person)
One paper plate
½ pull-and-peel twizzler
One normal twizzler
One fruit roll-up
One hard candy
Place on desk and DO NOT TOUCH
Make a Neuron!
Using all the types
of candy provided,
make a neuron!
Use your journal
picture (and this
one) to help you!
Now…
With your table partner, place each of your
axons next to each other in the way that axons
are oriented in our body.
How is the signal passed from one to another?
*Synapse =
small space
that separates
neurons
I will come give you some Nerds. Please break this
into little “neurotransmitters” to place between
your neurons to represent signal transmission
Signal Transmission*
• Neurotransmitter = a
chemical substance that is
released at the end of a
nerve fiber when an
impulse (signal) is passed
through
• By diffusing across the
synapse, causes the
transfer of the impulse to
another nerve fiber
What is this called??
Draw & Label
in Journal*
Neuromuscular Junction*
Place where
motor neuron
meets muscle*
Motor neuron =
muscle nerve
cell*
Muscle Contraction:
https://www.youtube.com/watch?
v=CepeYFvqmk4
Muscle Contraction*
1) Nerve impulse moves
through muscle fiber
2) Calcium channels open
and release calcium
3) Actin and myosin filaments
slide past each other
Men Experience Labor
Contractions
https://www.youtube.com/watch?v=qtR_-MINR1o
Send “fake” nerve signals to stomach muscles to
simulate the nerve signals sent during labor
Muscular System*
See attached document
Stretches/exercises to feel each muscle
What Makes Muscles
Grow?
https://www.youtube.com/watch?v=2tM1LFFxeK
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MCAS Questions
See attached document
The Nervous System:
The Nervous System:
Homework
Write a paragraph, using ALL the vocabulary
learned today, that describes the transmission
of a nerve impulse (signal) throughout the body.
Start with when a signal first hits the dendrites
of a neuron and how it ends with a muscle
contraction
(USE YOUR OWN WORDS!!!)
Next Day: Reaction Time Lab