Download Outcomes Assessment 76 Getting Organized Lesson Vocabulary

Body Works–Atlantic Teacher's Guide
11
Lesson
Student Book pages 42–45
In this lesson: Students learn how muscles
make their body move, why they need energy,
and why exercise is so important. They also get
more details about how the heart functions.
Outcomes
Students will have opportunities to:
• demonstrate how the skeletal, muscular, and
nervous systems work together to produce
movement (302-6)
• describe examples of health and fitness
programs within their community and region
(107-5)
• select and use tools in building models of
organs or body systems (205-2)
• identify problems and work cooperatively
with other students to refine their design of a
model of an organ or system (207-5)
Also: 302-5d
Assessment
• Check students’ design and description of a
muscle model to assess their understanding of
body movement. (302-6)
• Monitor the process of devising appropriate
muscle models during the Exploration. Note
how students use the materials at hand, and
the alterations or refinements they make to
improve the model. You can use the
Designing and Making Models Rubric in the
Program and Assessment Guide to assess
students’ proficiency. (205-2, 207-5)
• After they have completed Reproducible 11:
How Does Exercise Affect My Muscles?,
have students select a mode for explaining
the benefits of exercise, using their Science
Journal. Ask students to list the opportunities
for exercise in their community. (107-5)
Getting Organized
Time required: Activate 10-15
minutes; Explore two sessions of
30-35 minutes each; Apply 5-10
minutes a day for a week, plus
time for extending activity
Materials: rubber ball; index cards, scissors,
markers, hole punch, paper fasteners, ribbon;
other possible Exploration materials such as
cardboard tubes, elastic bands, and so on
Advance preparation: Gather materials;
prepare copies of Reproducible 11.
Lesson Vocabulary
biceps: the large muscle at the front of the
upper arm.
EKG (electrocardiogram): a visual record of the
electric current produced by the heart’s
contractions.
pacemaker: a bundle of nerve cells in the heart;
it sends an electric current to control the
heart’s contractions; an artificial device that
performs the same function when attached to
the heart.
tendon: a strong band of tissue that joins a
muscle to a bone.
triceps: the large muscle at the back of the
upper arm.
Content Background
Y
our muscles are sheath-like bundles of
fibres that contract and relax in
unison. The kind of muscles you control
consciously are called skeletal, or
voluntary. For example, the biceps in your
upper arm is a voluntary muscle connected
to your lower arm. When this muscle
contracts, it shortens in length and
increases in diameter, creating a bulge.
When it relaxes, it lengthens, its diameter
decreases, and the bulge disappears. When
it contracts, it pulls the lower arm toward
the upper arm. Like all muscles, the biceps
can only pull, never push.
Muscles are connected to bones by
strong white cords of fibres called tendons.
One end of a tendon moves outward from
the end of the muscle, the other is woven
into the bone. Muscles move bones by
pulling on tendons.
Skeletal muscles work in pairs. For
example, your biceps muscle pulls your
lower arm toward your upper arm, and its
partner, your triceps muscle, pulls it away.
Only one muscle in a pair works at a time.
Muscles that decrease the angle between
two bones are called flexors; those that
increase the angle are called extensors.
Anyone who has worn a cast for
several weeks has noticed how the body is
affected by lack of exercise. When the cast
comes off, the muscles look smaller and
are very weak. Muscle atrophy, as it is
called, is caused by lack of exercise.
Exercise strengthens injured or weak
muscles—as well as healthy ones—by
increasing the number of blood vessels in
the muscle tissue, thereby increasing the
blood flow to the tissue. More blood means
more nutrients available to produce energy.
While nutrients cannot increase the number
of fibres in a muscle, they can cause the
existing fibres to increase in size.
Involuntary muscles operate organs
without your conscious control. They are
controlled by their own set of nerves. For
example, there are self-exciting cells
embedded in your heart tissue that regulate
your heartbeat. These cell bundles respond
to signals from your heart’s built-in
pacemaker, which responds to signals from
your automatic nervous system.
Some of your involuntary muscles,
especially those pumping your heart, are
also affected by exercise. While you are
exercising, or if you are under stress, you
breathe harder. Because your cells need
more oxygen to produce more energy, your
heart pumps faster.
Regular exercise can actually increase
the dimensions of the heart, enabling it to
operate more efficiently—the same heart
rate now sends more nutrients and oxygen
to the cells. Athletes frequently have large,
slow-beating hearts because exercise has
increased the size and strength of their
heart muscles.
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Lesson 11: What Makes Your Body Move?
Lesson 11: What Makes Your Body Move?
Activate
E x p l o re
A
Preparing for the Exploration
Interpret your results.
Healthy Exercise
Suggested grouping: pairs
(Student Book page 42)
(Student Book page 44)
Materials per group: Index card, scissors,
marker, hole punch, paper fastener, ribbon;
also a variety of objects students may want to
select from for their own Exploration:
cardboard tubes, elastic bands, and so on
• One “bone” should move toward the other
one, depending on which “muscle” is pulled.
• Muscles always pull, and both muscles of a
pair cannot move at once.
• It could not work.
• Have students discuss with their classmates
what they think they have learned, in
preparation for writing up their Exploration.
Before reading, ask students:
sk students to lay one hand palm up on
their desk, with their arm completely at
rest. Have them press the flesh on both the top
and the bottom of their arm. What do they
observe? (flesh is soft) What happens when
they bring their lower arm up toward them?
(top bulges and becomes firmer, bottom stays
soft) What happens if they clench their fist?
(top bulges even more and becomes quite hard,
bottom becomes firm)
Ask students what they think happened to
create the changes they observed. Record their
answers and return to them later.
Read aloud the introductory paragraph on
page 42. Ask students what kind of muscle
their arm muscle is. How do they know?
Review what they already know about some
of the involuntary muscles in their digestive,
respiratory, and circulatory systems. Record
their ideas.
To demonstrate the properties of the heart
muscle, have students take turns trying to
squeeze a rubber ball with their hand, hard,
once every second. How long does it take
before their hand gets tired? Point out that
their heart beats more than once every
second—and never stops! Why do they think
their heart never gets tired?
Record specific responses to the final
question of the introductory paragraph.
Approximate time: 30 minutes
Classroom management: For the demonstration
model, it is important for students to cut and
punch the cards exactly as shown.
Communicate your results.
• Remind students to use the accepted format
for describing the process and results of their
Exploration.
(Student Book page 42)
Make a muscle model.
1. Explain that the two parts of the card
represent the upper and lower arms.
2. Ask students what the paper fastener and
the ribbon represent. (elbow and tendons)
3. Encourage careful observation and detailed
recording.
4. Now that students understand how muscle
movement can be demonstrated in a simple
way, their own creativity will take over.
Simply be there to answer questions—or ask
some if a focus is needed.
Exploration Connection
(Student Book page 43)
Your muscles
Read aloud the first paragraph and have
students respond. Ask them how they
control their muscles. Record their responses.
Have them read the rest of the page and return
at once to their recorded responses to see how
accurate their ideas were.
Look at the diagrams together. Make sure
students understand how both muscles and
tendons work.
Helping the ESL Student
Troubleshooting
Remind students that they should punch the cards
and thread the ribbons as shown if they want the
model to work properly—and follow the same
pattern in their own models. You might want to
demonstrate what happens if the “muscles” are not
properly attached.
Ask students to work in teams to create a
poster about the benefits of exercise. Have
them use English or their primary language, or
a combination of both. They can make their
own drawings or cut and paste images and text
from exercise and health magazines, health
food brochures, gym flyers, or other sources.
Display the posters in the classroom.
What activities do you do every day that
give you exercise?
If they name only sports, ask additional
questions to help them realize that all sorts of
activities provide them with exercise. For
example, ask:
Does anyone ride a bike to school?
Have students read the text on page 44 and
discuss the concepts of stamina, strength, and
flexibility. They should understand that their
muscles will get larger with regular exercise.
Review the suggestions for making a chart
with students and, if necessary, help them get
started. After they have completed their charts,
have them share their information as a class.
Ask the class to work together to develop a
set of criteria for rating the amount and kind
of exercise they get. Have them decide how
they could improve their health with respect to
exercise.
Have students study the chart. Ask them if
any of their favourite activities are included.
Explain that athletes have special training
programs and do many different exercises.
Although overall body strength is important to
all athletes, many focus on one part of their
body. Ask, for example:
What part does a speed skater focus on?
(legs) A swimmer? (arms)
Make sure students understand the Be
Aware! warning: warm-up and cool-down
activities prevent muscle damage.
This may be a good time to discuss other
effects of exercise on the body. Explain, for
example, how exercise burns excess calories
and fat, speeds up removal of body wastes, and
reduces the effects of stress.
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Lesson 11: What Makes Your Body Move?
Lesson 11: What Makes Your Body Move?
Apply
Closer to Home
(Student Book page 45)
Keep that pump pumping
After they have read this information, ask
students to summarize what they have learned
about the heart and how it functions. Their
response to the question should include an
understanding that pacemaker signals necessary
for the muscular action of the heart can be
artificially triggered.
Have students review any thoughts about
the heart that you recorded earlier and
consider how their ideas have changed.
You might focus briefly on the concept of
blood pressure. Explain that a person’s blood
pressure is indicated by two numbers: 120 over
80, for example. The larger number indicates
the amount of pressure on the artery wall when
blood surges through from the heart; the
smaller number indicates the amount of
pressure on the blood between surges. Students
will be amazed to learn that the amount of
pressure in the aorta is so great that if it were
cut, blood could squirt a distance of two
metres into the air!
Have students test the effects of exercise on
their leg muscles and complete Reproducible
11: How Does Exercise Affect My Muscles?
Every day for a week they should follow the
directions on the sheet and record the results.
What do they notice at the end of the week?
• A pacemaker regulates heart beat.
Troubleshooting
If any students are physically challenged,have them
exercise whatever body part is most appropriate,
including facial muscles.
Ask students to think about people they
know in real life or in the media whose
muscles are especially well developed. Ask:
What kind of people need extra strength,
stamina, or flexibility for their regular
activities?
(Students may mention a variety of sports
professionals, construction workers, and so on.)
Why do some people decide to build their
body beyond what they need for work or
health?
(They may be concerned about how others
perceive them: their looks, their health, their
power, their ability to “win.” Students may refer
to TV role models people try to imitate.)
Why are super-big muscles an unreasonable
health goal?
(Too much muscle can make a body function
less, not more, efficiently.)
Helping the Struggling Student
Creating and using definitions of lesson
vocabulary may help struggling students come
to grips with the concepts. Invite students to
work in pairs to prepare a crossword puzzle
using words from this and/or other lessons.
You can help them identify key terms.
Have each pair prepare a blank crossword
grid on a sheet of paper, with a one-sentence
clue for each term, based on information from
the Student Book. For example, for nerves the
clue could be: They control muscle movement.
Students can exchange their puzzles with others
and solve them.
Extending Learning
Canadian Research
Point out to students that Canadian scientists
have made major contributions to medical
research. One such scientist is Ray Chu-Jeng
Chiu, who has developed a way to use back
muscle to help strengthen a weak heartbeat.
Since the heart is the only muscle that can
contract constantly without tiring, it was
impossible to use other muscle tissue to help
repair heart damage. Chiu discovered a way to
use back muscle, by giving it constant
stimulation for several weeks beforehand.
Invite students to research to find out how that
is done and why it is necessary.
Integrating Science
Health: Physical Training
Have students imagine they are going to
train for some physical challenge, like a
swimming competition, a bike race, or crosscountry skiing. Let them choose their
challenge and explore how to train for it.
Which parts of their bodies will take the
most stress? How will they prepare their
heart and lungs for the extra work?
Encourage them to look at training books
and consult exercise instructors. They can
share what they learn with the class by
demonstrating one of the training exercises
and explaining how it would help them
condition their body.
Global Perspectives
In China, body care is a cherished tradition
designed to improve one’s strength and extend
one’s lifespan by maintaining physical fitness.
Part of the tradition includes breathing
exercises and the slow, methodical movements
of a 1000-year-old form of shadowboxing
called Tai Chi Chuan. Those who practise Tai
Chi move through the postures in a slow,
balanced way—the slower the movements, the
more adept the person. In modern China, you
often see people practising Tai Chi in outdoor
plazas and parks. Also, in many workplaces
people stop working in the middle of the
morning to do exercises to music.
The tongue is made up of bundles of
muscles that pull in many different
directions. That’s why a person can
move it in so many precise
directions and ways.
Few students will have first-hand experiences
to share, but most will understand that
exercise is necessary to firm and build muscle
fibres.Therefore, when the production of
energy in the muscle cells ceases,the muscle
fibres become smaller and weaker.
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Lesson 11: What Makes Your Body Move?
Lesson 11: What Makes Your Body Move?
11
Name __________________________________________ Date _____________________________________
How Does Exercise Affect My Muscles?
Sit on a chair and raise one leg parallel to
the floor. Record how long you can hold it in
that position. Rest for a minute and repeat.
Rest again and repeat.
DATE:
DATE:
RIGHT
LEFT
RIGHT
LEFT
FIRST TRY
SECOND TRY
THIRD TRY
DATE:
DATE:
RIGHT
LEFT
RIGHT
LEFT
FIRST TRY
SECOND TRY
THIRD TRY
DATE:
DATE:
RIGHT
LEFT
RIGHT
LEFT
FIRST TRY
SECOND TRY
THIRD TRY
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Lesson 11: What Makes Your Body Move?
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