Nervous System {Word Document}

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TEKS 10 A & B, 11C
Nervous System
TAKS Objective 2 – The student will demonstrate an understanding of
living systems and the environment.
TEKS Science Concepts 10 A & B
The student knows that, at all level of nature, living systems are found
within other living systems, each with its own boundary and limits. The
student is expected to:
(A) interpret the functions of systems in organisms including
circulatory, digestive, nervous, endocrine, reproductive,
integumentary, skeletal, respiratory, muscular, excretory, and
immune;
(B) compare the interrelationships of organ systems to each other
and to the body as a whole;
11 C
The student knows that organisms maintain homeostasis. The student is
expected to:
(C) analyze the importance of nutrition, environmental conditions, and
physical exercise on health
TAKS Objective 2
page 1
BIOLOGY
For Teacher’s Eyes Only
Teacher Background: There are twelve major organ systems in the human body
(i.e., circulatory, skeletal, respiratory, excretory, integumentary, nervous,
digestive, endocrine, reproductive, immune, lymphatic, and muscular systems). In
this TEKS, we will introduce students to the common structures of each system
and their basic functions. A brief description of these systems follows:
Nervous System – The nervous system is interrelated with all other systems. It
controls, regulates and communicates with all the other body systems. The
nervous system is also the hub of all mental activity including memory, thought,
and learning. The nervous system consists of the brain, spinal cord, nerves, and
neurons. These organs work together with the organs of the endocrine system to
collect information about the external environment and determine how it relates to
the body’s internal state. The nervous system then compiles this information and
initiates the body’s response to maintain homeostasis.
The nervous system is broken into two separate systems, the Central Nervous
System and the Peripheral Nervous System. The central nervous system (CNS)
consists of the brain and spinal cord, while the peripheral nervous system (PNS)
includes all the nerves that collect information about the external and internal
environment to be quickly interpreted by the spinal cord. Beating of the heart and
digestion of food is under the control of the peripheral nervous system, which is
responsible for unconscious body functions. However, the PNS can be further
subcategorized into the Sympathetic and Parasympathetic Systems. These two
systems keep each other in check by working in opposing action to one another.
Student Prior Knowledge
Students should be familiar with the components associated with body systems
TEKS 6.10 (C) identify how structure complements function at different levels of
organization including organs, organ systems, organisms, and populations and the
functions of these systems.
TAKS Objective 2
page 2
BIOLOGY
Neurons and Nerves
5 E’s
ENGAGE
Lorenzo’s Oil
Discuss the film guide and review the nervous system concepts that were covered
in this film
EXPLORE
Exploration 1
Quick Communication
UNC-CH Brain Explorer
Students will be introduced to neurotransmission in the context of a reaction time
experiment that demonstrates the concept of gravity and the reaction of the
nervous system.
Part I Set-up:
-A book
-Paper
-Ruler
-Reaction Time poster
-Dry erase marker
-Student Worksheet “Reaction Time Part I”
PROCEDURE
Bring out a ruler and ask a student volunteer to come up to the front of the class.
Instruct the student to catch the ruler as it is dropped.
• After the ruler is caught, ask student:
"Why was the ruler caught in the middle (after a lag period) rather than at the end
(instantaneously)?
TAKS Objective 2
page 3
BIOLOGY
"What causes this hesitation?"
“What had to happen in my body for me to catch the ruler?”
• Have students predict the sequence of events involved in the reaction time
pathway.
• Ask students what had to happen for you to grab the ruler after it dropped.
• Demonstrate visually the process using the REACTION TIME POSTER.
Use the dry erase marker to draw the reaction pathway:
The eye sees the ruler drop.
The eye sends a message to the visual cortex.
The visual cortex sends a message to the motor cortex.
The motor cortex sends a message to the spinal cord.
The spinal cord sends a message to the hand/finger muscle.
The finger muscle contracts to catch the ruler.
• Distribute the worksheet and have students complete the top portion by writing
the 5 key words from the word box in the correct order.
• Have students complete the lower portion of the worksheet. They must write a
short paragraph detailing the reaction sequence listed above (there are 6
components).
Part II Set-up:
-Distance/Time chart
-Rulers (class set)
-Reaction Time poster
-Dry erase marker
-Student Worksheet “Reaction Time Part II”
After students have completed their reaction sequence paragraph perform the
following:
• Ask students, "What is speed and how do we measure it?"
• Think of the speed that you drive a car. "What two units of measurement are
used to describe the rate of a moving car?" Speed has two components: distance
and time (miles/hour).
• Show the students the ruler once again, and ask them, "How can we use this
ruler to measure our reaction time?" Students should recognize that we have a
distance component, but not a time component.
• Students should hypothesize methods for measuring time. Ideally, one student
will suggest using a stopwatch.
• Have two student volunteers come to the front of the class. One student will
catch the ruler as the teacher drops it, while the other student measures the
reaction time. This demonstrates that our reaction times are less than a second,
which is too short to be measured with a clock, watch, or stopwatch. Though this
method for measuring reaction time is theoretically possible, it is simply too
difficult to measure our reaction times manually.
• Introduce students to the distance time chart created by scientists.
TAKS Objective 2
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BIOLOGY
Discuss that we will be using this chart instead of calculating reaction times
ourselves. We are able to use this chart since we know that all objects fall at the
same rate in the absence of wind resistance (Galileo's Law).
• Discuss the use of milliseconds on the distance time chart. Ask students how
many milliseconds are in one second. Ask students to brainstorm what they can
react to in less than a second. Ex: pulling a hand quickly away from a hot object.
• Review technique/methods for measuring ruler catch distances. Stress the
importance of standardization.
• Students should round up to the first whole number above their finger/thumb
every time they take a measurement. Also, students should keep the same distance
between their finger and thumb and the ruler each time they take a measurement.
• Review the distance time chart and how to calculate reaction times.
• Distribute the reaction time worksheets and complete the top portion on
recording data with the students.
• Before beginning the experiment, students make predictions regarding which
hand will be better at catching the ruler (faster). Teachers can use this opportunity
to reinforce prediction/hypothesis formation. “How is a prediction different from
a guess?”
• Students work in pairs to practice catching the ruler and determining their
reaction times.
• Explain to students that they will each have the opportunity to catch the ruler 3
times (each hand). Then they will record the 4th catch distance and reaction time
for each hand. They will record these measurements on their worksheet as their
official reaction times.
* If students are able, the three trial catch distances can be averaged to determine
a more accurate estimate of reaction time. This is a good opportunity to introduce
averaging if this topic is new to students.
• Distribute rulers and begin experiment.
• Students conclude by reflecting on whether their prediction was correct or
incorrect and why.
• Volunteer students can share their experiment results with the class.
• Teacher and students discuss differences between left and right hands.
"Why do you think one is faster than the other?" (Greater practice and use of one
hand.) "Did you get faster at catching?" "Do you think we can improve our
reaction times with practice?"
• Discuss reasons why the students’ time might not have improved, like they were
too excited or nervous to concentrate.
• Students complete a handout describing the reaction process and put steps in
sequence.
• See if any students are able to narrate the reaction time sequence.
On-line Extension
• The Neuroscience for Kids website has on-line reaction time experiments that
would be a great supplement to this lesson (particularly for students who finish
early).
• Go to http://faculty.washington.edu/chudler/chreflex.html and scroll down to the
“How Fast Are You?” section for 3 different on-line reaction time experiments.
TAKS Objective 2
page 5
BIOLOGY
Exploration 2
Beady Neurons
EXPLAIN
Complete the Nervous System PowerPoint presentation with discussion and
then divide students into teams to explain and answer questions while playing
neuro-jeopardy. See neuro-jeopardy power point. Students should be capable
of answering questions like the ones that follow:
ELABORATE
Neurotransmission: Nifty Neurons and Muscle Messages
Modified from UNC-CH Brain Explorers
Materials:
• Reaction Time poster
• Neuron Structure poster
• White 8 x 11 paper
• Class set of pastels
• Small soft ball
Reaction Time Review
Review the engage activity reaction time experiment, using the ball and throwing
it from one student to another for each step.
The teacher can start the process; throw the ball to a student who identifies the
next step. The ball is thrown to successive students until all the steps have been
reviewed.
1. The eye sees the ruler drop.
2. The eye sends a message to the visual cortex.
3. The visual cortex sends a message to the motor cortex.
4. The neuron in the motor cortex sends a message to the neuron in the spinal
cord.
5. The neuron in the spinal cord sends a message to the muscle cells in the hand.
6. The muscles in your hand contract to catch the ruler.
TAKS Objective 2
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BIOLOGY
Nerve Cell Review
• Ask students, "How are messages sent from place to place?" (i.e., eye to visual
cortex, or visual cortex to motor cortex). Encourage students to consider the role
of neurons in this process.
• During the discussion, reveal facts about neurons such as the ones below.
- Neurons carry messages in our bodies.
- There are neurons that connect each point in the reaction time pathway.
- Neurons are the building blocks of our nervous system.
- The human brain contains about 100 billion neurons, each of which
communicates with thousands of other nerve cells that together, control our every
perception and movement.
- Neurons allow us to breathe, move, feel, learn, remember, etc.
• Ask students to recall what they learned about the structure of a neuron. Have
students brainstorm the neuron terms that they know and write them on the board.
• Hopefully students will remember that a neuron/nerve cell has several parts:
dendrites, axon, cell body, nucleus, axon terminal, neurotransmitters,
neurotransmitter, and receptors.
• Use the neuron structure poster to review and discuss neuron structure.
Nerve Cell Drawing
• Students draw and label neurons using white paper and pastels.
• Remind students that an important job of scientists is to record what they have
learned. Sometimes scientists do this by creating a drawing or sketch. Like a
scientist, the students are recording what they know about neurons, and it is
important to be as accurate as possible.
TAKS Objective 2
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BIOLOGY
Differences in Nerve Cells
• Ask students, “Why might some nerve cells have different numbers of dendrites
than others?”
• Students may discuss their hypotheses. Reveal that younger brains (0 to 2yrs)
have fewer dendrites than adolescent or adult brains because as you learn and use
new thought processes, you require more dendrites and connections between cells.
• In the artwork extension, students use Scratch LightTM paper to depict the
increasing complexity of neurons as a child grows.
EVALUATE
1. Using notes and text, students will compete to answer questions over the
nervous system by playing Neurojeopardy.
2. After constructing a clay brain model, students will verbally identify 6 of 7
brain structures.
3. Students will construct a neuron model with 100% accuracy that contains
dendrites, a cell body (soma), axon, and axon terminals.
TAKS Objective 2
page 8
BIOLOGY
TAKS Objective 2
page 9
BIOLOGY
Film Guide for Lorenzo's Oil
Please read these questions over before you see the film!!!
1. Show how Lorenzo's parents used the scientific method to solve their
problem. State the problem, ask a question and use examples from the film
to illustrate the steps.
2. From the description of the disease, ALD, sketch what Lorenzo's neurons
most likely looked like after a year. Include a sketch of a normal neuron.
3. ALD is a recessive sex-linked or X-linked disease. What are the probable
genotypes of the family members listed?
Aunt #1_______
Augusto_______
Aunt Dee_______
Aunt #2_______
Lorenzo_______
Michalla_______
TAKS Objective 2
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BIOLOGY
4. What is Lorenzo's Oil? How does it work? Use the sink model from the
film.
5. Explain Augusto's use of paper clips to represent good and bad fatty acids.
What did his dream help him understand?
6. Why did the medical community resist the Odones' treatment ideas? Why
did the parent support group resist? Give examples of arguments for and
against.
7. How do analogies help you to understand the scientific problem? How did
modeling help solve the scientific problem? Can you think of other great
discoveries that employed the use of models?
TAKS Objective 2
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BIOLOGY
8. How did Augusto and Michalla demonstrate "life-long" learning?
9. Defend the position that diseases that affect a small % of the population
should not get as much money for research as the big killers like cancer
and heart disease.
10. What was found out from the Polish biochemist? What was the purpose of
the ALD Symposiums? What happens when scientists work in isolation?
11. What is erucic acid?
12. Where was the myelin research being done? What was the experiment?
How could this research help Lorenzo?
TAKS Objective 2
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BIOLOGY
Neuron Models
1. You should have four different colors of modeling clay or playdough. You
are to build a model of a nerve cell using different colored clay for the various
parts of the neuron. Remember the neuron has four basic parts.
2. Once you have finished your model, place your neuron in the box below.
3. Label and draw arrows to the following:
1.
2.
3.
4.
5.
Dendrites
Soma or Cell Body
Axon
Axon terminal
Draw an arrow to indicate the path that an impulse will travel on your
neuron
TAKS Objective 2
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BIOLOGY
TAKS Objective 2
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BIOLOGY
Name: _____________
Date: ______________
Brain Explorers
Reaction Time Part I Student Worksheet
Word Box
Visual Cortex
Muscle
Spinal Cord
Motor Cortex
Eye
The words in the word box name the parts of your body involved in
creating a response (ex. catching a falling object). Put the words in
order according to how they are used in the body.
1. _______________________________
2. _______________________________
3. _______________________________
4. _______________________________
5. _______________________________
Now use these words, in the proper sequence, to write a paragraph
describing the process that allowed you to catch the ruler.
____________________________________________________
____________________________________________________
____________________________________________________
____________________________________________________
____________________________________________________
____________________________________________________
____________________________________________________
____________________________________________________
____________________________________________________
____________________________________________________
____________________________________________________
____________________________________________________
____________________________________________________
____________________________________________________
______________________________________
TAKS Objective 2
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BIOLOGY
Brain Explorers
Reaction Time Part I
Teacher Key
The words in the word box name the parts of your body involved in
creating a response (ex. catching a falling object). Put the words in
order according to how they are used in the body.
1. Eye
2. Visual Cortex
3. Motor Cortex
4. Spinal Cord
5. Muscle
Now use these words, in the proper sequence, to write a paragraph
describing the process that allowed you to catch the ruler.
First, your eye sees the ruler. Then, your eye sends a message to
the visual cortex, which sends a message to the motor cortex.
The motor cortex sends a message to the spinal cord. The spinal
cord sends a message to the muscles in your hand/fingers. Finally,
your muscles contract to allow you to catch the ruler.
*Student responses may vary, but they must include the major
components of the neural process.
TAKS Objective 2
page 16
BIOLOGY
Neurotransmission: Nifty Neurons
TAKS Objective 2
page 17
BIOLOGY
Brain Explorers
Nerve Cell Drawing—Teacher Guide
The following neuron structures should be included:

Cell body with dendrites
• Nucleus
• Axon
• Axon terminal
• Muscle cell (optional)
The following labels should correspond to the neuron drawing:
• Neuron or nerve cell
• Cell body
• Dendrites
• Nucleus
• Axon
• Axon terminal
• Muscle cell (optional)
TAKS Objective 2
page 18
BIOLOGY
TAKS Objective 2
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BIOLOGY
Distance and Time Chart
Reaction Time
Catch Distance
(in centimeters)
Seconds
Milliseconds
5
.100
100
6
.107
107
7
.114
114
8
.121
121
9
.128
128
10
.135
135
11
.142
142
12
.149
149
13
.156
156
14
.163
163
15
.170
170
16
.177
177
17
.184
184
18
.191
191
TAKS Objective 2
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BIOLOGY
Name: _______________________
Date: _______________________
Brain Explorers
Reaction Time Experiment Record Sheet
Things to remember when measuring your catch distances on your
ruler:

Start with the “0 cm” end of
the ruler at the bottom, &
have your partner hold the
ruler just above your fingers.

After you catch the ruler,
record the number right
above your thumb. What
number would you record for
this “catch distance”?
a) 14 cm
b) 15 cm
c) 16 cm

Example: Which ruler “catch
distance” would you record?
a) 7 cm
b) 8 cm
c) 9 cm

If your catch distance is 13 cm, what is
your reaction time?
a) 144 milliseconds
b) 177 milliseconds
c) 156 milliseconds
TAKS Objective 2
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BIOLOGY
Make a prediction:
I think my reaction time will be faster with my (right/left)
_____________ hand.
Record your “catch distances” in the spaces below. Then use the
“distance & time” chart to find how long it took you to catch the ruler.
Right Hand
Trial
1
2
3
4
Catch
Distance
Left Hand
Reaction
Trial
Time
(milliseconds)
1
2
3
4
Trial
Catch
Distance
1
2
3
4
Reaction
Trial
Time
(milliseconds)
1
2
3
4
Use your 4th or last catch distance to determine your official
reaction times.
My right hand reaction time is ______________ milliseconds.
My left hand reaction time is _______________milliseconds.
“Do you remember your prediction?
Was your prediction correct? Which hand was better at catching the
ruler? Why was one hand faster than the other?
TAKS Objective 2
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BIOLOGY
Central Nervous System
5 E’s
ENGAGE
EXPLORE
Exploration 1
Clay Brains
UNC-CH Brain Explorers
Students will be introduced to basic brain anatomy. They will hear and say the
terms associated with basic brain anatomy and create reasonably accurate clay
models featuring all the major structures.
Set-up:
• How to Build a Brain Worksheet
• Plastic Brain Models
• Paper (to protect desks)
• Set of clay in 4 or 5 colors for each student
PROCEDURE
• Display several small brain models to the class.
• Tell students that they will be making brain models
• Pass out the following to each student:
out of clay.
- a small resealable plastic bag containing four or five different colored cubes of
modeling clay;
- a blank sheet of paper to use as a work surface; and
- a ‘How to Build a Brain’ worksheet.
• Have a student read the first paragraph of the worksheet aloud to the class.
This paragraph introduces the term ‘hemisphere’, and discusses why scientists use
Greek and Latin terms. Have all the students create two hemispheres.
TAKS Objective 2
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BIOLOGY
• Have another
student read the next paragraph of the worksheet. This paragraph
introduces the terms ‘cortex’ and ‘corpus callosum’. Encourage students to
examine the small model brains to become familiar with where the structures are
located in an actual brain
• As the students finish each step of the directions, go around the room and make
sure that the hemispheres are reasonably well shaped, and that the corpus
callosum is in the proper position before the hemispheres are placed together.
• When all the hemispheres are connected, ask a student to read the next paragraph
of the worksheet. This paragraph introduces the terms ‘gyrus (pl.
gyri)’and ‘sulcus (pl. sulci)’. Students can reproduce these structures either
by rolling up gyri or drawing grooves (sulci) on their cortices with a pencil point.
• Encourage students to refer to the model brains for guidance.
• Ask a student to read the next paragraph of the worksheet. This introduces the
term ‘cerebellum’; then instruct the students to make a cerebellum and attach it to
their models.
• Make sure the cerebellums are attached to the proper point on the clay models.
Refer to the plastic models for proper placement.
• Have the next paragraph read. This deals with the ‘brain stem’, the structure that
connects the brain with the spinal cord. The students should make a brain stem
and attach it to the proper location on their clay brains.
• Go around the room and answer questions from the students.
Again, encourage the use of proper vocabulary when the students ask questions.
• After the clay brain models are completed, have the students use the checklist on
the last page of the worksheet to make sure their models are correct.
• Each student should show a classmate their model, naming all the parts on the
checklist.
• Go around the room and have various students name the parts of their models.
EXPLAIN
Complete the Nervous System PowerPoint presentation with discussion and
then divide students into teams to explain and answer questions while playing
neuro-jeopardy. See neuro-jeopardy power point. Students should be capable
of answering questions like the ones that follow:
TAKS Objective 2
page 24
BIOLOGY
ELABORATE
Elaboration 1
Nicotine in the Body and Brain
The goal of this lab is for students to understand how cigarette smoke travels
through the respiratory system and the bloodstream to the brain.
Set-up:
-Nicotine and the Respiratory System poster
-White paper for each student
-Colored pencils to share
PROCEDURE
Part I – Body:
Brainstorming: Reasons for Smoking
• Tell students that in today’s lab they will learn how cigarette smoke travels
through the body.
• First ask: What reasons might people have for smoking cigarettes?
• Create a class web listing reasons people might smoke cigarettes.
• Ask students what cigarettes are made of *tobacco, paper, filters.)
• Describe the contents of cigarette smoke. These include nicotine, burned tar,
ammonia, and carbon monoxide.
• Ask where cigarette smoke goes after a person inhales. “Where in the body does
it travel?”
• Explain that nicotine enters the body through a nicotine/tar mixture that is
inhaled from a lit cigarette both through the mouth and the nose.
• Nicotine travels through the respiratory system before reaching the bloodstream.
• Using the poster of the respiratory system, identify the different parts of the
respiratory system.
• Explain the sequence followed by nicotine as it travels through the respiratory
system:
-Air goes in through the nostril & into the nasal cavity. The pharynx is the area in
the back of the throat, the larynx (voice box) is just below (posterior to) that.
-Air then travels down the windpipe (trachea), which branches into two bronchi
(one bronchus leads to each lung).
-Once inside the lung the bronchi branch out into smaller tubes called bronchioles
which lead to clusters of air sacs. The air sacs are called alveoli. Here, nicotine
can move from the lungs into the bloodstream where it is delivered to all parts of
the body including the brain.
Emphasize that the tar is known to cause cancer and the nicotine is highly
addictive.
TAKS Objective 2
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BIOLOGY
• Ask students to use art materials to draw the human body and the path of
cigarette smoke/nicotine from the cigarette to the brain.
• Students can take any approach to their art work as long as they show the
cigarette, and nicotine moving through the respiratory system into the lungs and
then the brain.
• The different parts of the respiratory system should be labeled.
Part II – Brain:
Set-up:
-Neurotransmission dance materials (with the addition of
nicotine-related items)
-Labels
-Props
-Various musical instruments
-Nicotine and Neurotransmission Poster
• Ask students what happens next?
• What effects do they think nicotine has on the brain?
Explain the effects of nicotine on the body:
1. Increases in blood pressure and heart rate.
2. Faster respiration.
3. Constriction of arteries.
4. Stimulation of the central nervous system.
• Review the process of neurotransmission.
• Have students identify parts of this process that could be impacted by nicotine.
• Ask students: what normally stimulates the nervous system? Try and illicit that
when nerve cells are sending messages, neurotransmitters are required in the
process to excite the cell.
• Explain to students that nicotine acts like a neurotransmitter for specific
receptors on nerve cells.
• Nicotine over stimulates the cell, more than it is stimulated by the
neurotransmitter which it normally binds with.
• When there is no nicotine, the cell does not get as excited as when it binds with
the normal neurotransmitter. This makes the smoker want to have another
cigarette to achieve the same effect.
• Be sure students understand that cigarettes have different effects for different
people depending on the dose, their mood and their smoking history.
• Also, scientists are not entirely certain how nicotine causes dependency and
addiction. However, nicotine’s ability to alter the normal process of
neurotransmission is thought to play a critical role.
TAKS Objective 2
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BIOLOGY
Neurotransmission Dance
• Using the Nicotine and Neurotransmission poster, clarify the effects discussed
above.
• Tell students they will now do the neurotransmission dance to show nicotine’s
effects.
• This neurotransmission dance will include three nerve cells.
• Thus more props will be used and props for nicotine, including labels, and a
nicotine costume will be introduced.
• In Dance 1 neurotransmission is normal between all three cells, and includes
four neurotransmitters at each synapse.
• In Dance 2 neurotransmission does not occur between the first and second cell
but nicotine enters between the second and third cell. Only two nicotine
neurotransmitters are released but they excite the cell beyond normal
transmission.
• In Dance 3 neurotransmission occurs between cell 1 and 2 and is normal but
neurotransmission between cell 2 and 3 barely excites the cell and does not result
in the message being passed on, or the action potential being released in cell 3.
EVALUATE
1. Using notes and text, students will compete to answer questions over the
nervous system by playing Neurojeopardy.
2. After constructing a clay brain model, students will verbally identify 6 of 7
brain structures.
3. Students will construct a neuron model with 100% accuracy that contains
dendrites, a cell body (soma), axon, and axon terminals.
TAKS Objective 2
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BIOLOGY
TAKS Objective 2
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BIOLOGY
How to Build a Brain
Today we are going to build a brain out of clay. To do
this, we will need to make the different parts of a
brain. The first part we need to make is a half of
the biggest part of the brain, called a hemisphere.
Hemisphere is a Greek word that means half (hemi)
of a round shape (sphere). Scientists use Greek and
Latin words to describe different shapes and
structures. These are very old languages that
scientists like to use to describe things they
discover or observe.
Two Hemispheres
Two Hemispheres
After you make one hemisphere, make another
one the same size. The outside of the hemisphere is
called the cortex. This is Latin word that means
“bark”, like the bark of a tree. The cortex protects
the inside of the brain the way the bark protects
the inside of a tree. The two hemispheres are
connected by a bridge called the corpus callosum.
TAKS Objective 2
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BIOLOGY
These strange sounding words mean “hard body” in
Latin. Put a small piece of clay in the middle of one
of your hemispheres before you mold them together.
The outside of the cortex is covered by shapes
that look like wads of gum. One of these wads is
called a gyrus. Two or more are called gyri. Gyrus is
a Latin word that means ‘roll’ or ‘fold’. Between the
gyri are lines or grooves. One of these lines is called
a sulcus. This is another Latin word that means
‘furrow’, like the line a farmer cuts in the ground to
plant seeds. Two or more of these are called sulci
(sul-sigh). You can make gyri by rolling up thin piece
of clay and sticking them onto the cortex.
Now we need to make the cerebellum. The
Cerebellum is made up of the two rounded shapes
that look like a little brain at the back of the
cortex. Cerebellum means ‘little brain’ in Latin. Roll
up two smaller balls of clay and stick them where
you see the cerebellum on the model. Squish them
together a little, because unlike the hemispheres,
the cerebellum is not made up of two separate
pieces. Our brains are starting to look like real
brains!
Next we need to make a brain stem. The brain
stem is what connects the brain to the spinal cord.
The brain stem looks like the stem of a flower or an
apple. You should stick your brain stem between the
TAKS Objective 2
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BIOLOGY
two round shapes that make up the cerebellum. Look
at the model if you are not sure where to put your
brain stem. Unlike the model, the brain stem is really
made out of one piece, like the cerebellum.
Congratulations! You have built a brain! Can you
name the different parts of your brain? Show
someone your brain and point out the different
parts.
Here is a checklist of the parts your brain should
have:
*Right hemisphere
*Left hemisphere
*Corpus callosum (did you remember to put one
between the hemispheres?)
*What is the cortex? How is the cortex like a Roman
dog? (One is ‘bark’ in Latin, the other barks in Latin.)
Extra credit if you laughed.
*Gyri
*Sulci
*Cerebellum
*Brain stem
Take your brains home and show the different parts
to someone. How many of the parts did they know?
TAKS Objective 2
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BIOLOGY
Nicotine and the Brain
Normal Synaptic Conditions
* Under normal synaptic conditions, neurotransmitters are released from Cell 1 to
stimulate Cell 2.
Cell 2 then becomes excited, releases its action potential and transmits
neurotransmitters to Cell 3.
Cell 3 subsequently is excited and releases its action potential and the transmission
process continues.
Nicotine in the Synapse
* Below, Cell 2 does not receive any neurotransmitter stimulation from Cell 1. It
does not get excite and does not transmit any messages to Cell 3. Nicotine enters
the synapse and binds to the receptors on Cell 3 causing heightened excitation and
neurotransmission.
Synaptic Conditions After Nicotine
*In the absence of nicotine, the normal transmission process is impaired. Normal
stimulation of Cell 1 and subsequently Cell 2 is not enough to excite Cell 3. Cell 3
does not receive enough stimulation to release its action potential and continue the
transmission process.
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BIOLOGY
Peripheral Nervous System
5 E’s
ENGAGE
As a class visit IQ Test Labs at www.intelligencetest.com/reflex/index.htm
Select various students to come to the computer and test their skills on the
different reflex/reaction tests. This website states that scientific tests have shown
that reaction times to simple tasks have high correlations with g the general
intelligence factor. Students should have fun attempting these reaction time
games.
EXPLORE
Muscle Messages
UNC-CH Brain Explorer
The goal of this lab is to reinforce the process of neuromuscular transmission with
hands-on materials.
Set-up:
-Reaction Time poster
-Nerve-muscle poster
-Synapse poster
-Neurotransmission felt kits
-Synapse worksheet
Procedure:
• Review neuron structure with students.
• Ask students “How can these neurons send messages to each other and to the
muscle cell?”
TAKS Objective 2
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BIOLOGY
• Let students hypothesize as to what structures might be involved in
neurotransmission, which is the process of communication between nerve cells
and other cells in the body.
• Review the reaction process required to catch the ruler on the board: the
eye, the visual cortex, the motor cortex, the spinal cord, and the muscle.
• Tell students, “Let's focus on the neuron that carries the message from the spinal
cord to the muscles in the hand.” This nerve cell body is in the spinal cord and its
axon stretches out to the hand muscles.
• Students may enjoy estimating the length of their axons by measuring the
distance from the spinal cord to the hand with a meter stick.
• Tell students that they will next learn all the details about how the message gets
from the nerve cell to the muscle cell.
TAKS Objective 2
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BIOLOGY
Explain (10 minutes) Introduction to Neurotransmission
• Use the neurotransmission poster to explain the following sequence of events.
1. The dendrites of the nerve cell in the spinal cord get a message from the nerve
cell in the motor cortex.
2. The nerve cell in the spinal cord gets excited which causes an electrical signal,
or action potential, to move down the axon of the nerve cell (ie. the axon that
travels down the arm from the spinal cord).
Use the neuron and synapse posters to clarify the process.
3. Once the action potential reaches the axon terminal neurotransmitters are
released and travel through the synaptic cleft (the space between the axon
terminal of the nerve cell in the spinal cord and the receptors on the muscle cell)
to neurotransmitter receptors on the muscle cell.
4. The neurotransmitters and neurotransmitter receptors bind, which causes the
muscle cell to get very excited.
5. Once the muscle cell is excited then the muscle contracts (or moves).
• There are different levels of excitation in the receiving muscle cell.
Excitation is increased with the increase in neurotransmitters that are released.
The cell must be excited to a certain state before the muscle is able to contract.
Reaction Time Felt Kit
• Explain to students that they now
will put together and narrate the steps
of neuromuscular transmission using a
felt kit.
• Introduce the felt kit parts and labels:
placemat (white felt), neuron cell body
with dendrites (blue felt), axon and
axon terminal (gold bead chain),
action potential (lightening bolt),
neurotransmitters (fuzzy balls),
neurotransmitter receptors(y-shaped
felt), and muscle cell (arm, hand,
and muscle felt shape).
• Demonstrate the process once for the class, setting up and moving the various
parts. Repeat the sequence of events for the students.
• Students work in groups to put together the "neurotransmission scheme" on the
placemat.
• Encourage students to use the labels for each part of the kit and to practice
narrating the process to each other using the labels.
• Come together as a class and have a few student volunteers narrate the process
for the class.
• Be sure to remind students to use the materials carefully and make sure all the
pieces get back in the bag for the next class.
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BIOLOGY
Synapse Worksheet
• In the box, students should draw and label the synapse using all the words listed
• Students should then number the steps of neurotransmission from 1-6 beginning
with # 1 (the nerve cell in the spinal cord receives a message from the nerve cell
in the motor cortex).
EXPLAIN
Complete the Nervous System PowerPoint presentation with discussion and
then divide students into teams to explain and answer questions while playing
neuro-jeopardy. See neuro-jeopardy power point. Students should be capable
of answering questions like the ones that follow:
TAKS Objective 2
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BIOLOGY
ELABORATE
Reflex Arc Lab
http://educ.queensu.ca/~science/main/concept/biol/b06/B06LACW1.htm
To study the simplest functional unit of the nervous system: the reflex arc.
EVALUATE
1. Using notes and text, students will compete to answer questions over the
nervous system by playing Neurojeopardy.
2. After constructing a clay brain model, students will verbally identify 6 of 7
brain structures.
3. Students will construct a neuron model with 100% accuracy that contains
dendrites, a cell body (soma), axon, and axon terminals.
TAKS Objective 2
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BIOLOGY
TAKS Objective 2
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BIOLOGY
TAKS Objective 2
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BIOLOGY
TAKS Objective 2
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BIOLOGY
Name: _________________
Date: _________________
Brain Explorers
Neurotransmission Worksheet “Nerve cell to Muscle cell”
Using the words on the left, label the picture by drawing a line to
the parts of the picture.
muscle cell
cell body
axon terminal
dendrites
nucleus
nerve cell
neurotransmitters
Put the parts of the neurotransmission process in the correct
order. Label them from 1 to 6 in the boxes to the left of each
statement.
After the nerve cell gets excited, it sends the action potential
down the axon to the axon terminal.
Once the neurotransmitters bind to the neurotransmitter
receptors, the muscle contracts.
Dendrites on the nerve cell in the spinal cord receive messages
from another nerve cell.
The neurotransmitters travel to the neurotransmitter receptors
on the muscle cell.
The nerve cell gets excited.
When it reaches the axon terminal, neurotransmitters are
released.
TAKS Objective 2
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BIOLOGY
Name: _________________
Date: _________________
Brain Explorers
Neurotransmission Worksheet “Nerve cell to Muscle cell”
Teacher Key
Using the words on the left, label the picture by drawing a line to
the parts of the picture.
Put the parts of the neurotransmission process in the correct
order. Label them from 1 to 6 in the boxes to the left of each
statement.
3
After the nerve cell gets excited, it sends the action potential
down the axon to the axon terminal.
5
Once the neurotransmitters bind to the neurotransmitter
receptors, the muscle contracts.
4
Dendrites on the nerve cell in the spinal cord receive messages
from another nerve cell.
1
The neurotransmitters travel to the neurotransmitter receptors
on the muscle cell.
2
The nerve cell gets excited.
6
When it reaches the axon terminal, neurotransmitters are
released.
TAKS Objective 2
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BIOLOGY
Reflex Arc Lab
A: Purpose

To study the simplest functional unit of the nervous system: the reflex arc.
B: Materials

percussion hammer, glass rod, filing cards, nail, flashlight, 20x20cm piece
of newspaper, beaker
C: Method
Note: For the duration of this lab students should work in pairs
1. Patellar (knee-jerk) Reflex



Have the subject sit on the edge of a table with one leg dangling freely.
Strike the tendon just below the knee-cap with the hammer
Record the results
Sketch a diagram of the reflex arc and label the receptor, sensory neuron,
dorsal root, white matter, gray matter, ventral root, motor neuron, and
effectors.
2. Uvular Reflex



Have the subject open his/her mouth widely and touch the uvula with a
clean glass rod (or cue-tip).
Record the results
Of what value is this response to humans?
3. Pupillar Reflex






Have the subject close his/her eyes for 2 minutes
Hold a filing card along the bridge of the nose so the right eye is shielded
from the left.
Shine a bright light into the right eye as soon as the subject opens his eyes.
Observe the pupils of both eyes and record the response.
Explain the results
What could happen if this reflex did NOT exist?
TAKS Objective 2
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BIOLOGY
4. Accommodation Reflex


Focus both eyes on the tip of a pencil held at eye level and at arm's length.
While focusing on the pencil tip, indicate whether or not the objects in the
background are in focus.
Keeping the same line of sight, focus on the objects in the background.
What happens to the image of the pencil tip.
The distance from the eye to the nearest object that can be focused on clearly is
called the near point of vision. To find the near point:







Cover one eye, and focus on a piece of newspaper. Gradually bring the
newspaper closer and closer to your eye until the letters just go out of
focus.
Have your partner measure the distance (in cm) between the newspaper
and your eye.
Repeat steps 4 and 5 for the other eye.
Record the near point for both eyes.
Give a physiological explanation for what has occurred in both parts of
this experiment.
Why can a person not see objects clearly when they are positioned closer
to the eye than the near point?
What happens to the near point as a person ages? Why does this occur?
http://educ.queensu.ca/~science/main/concept/biol/b06/B06LACW1.htm
TAKS Objective 2
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BIOLOGY
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