Download Your health depends on the effective functioning of your

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B I G IIDDEEAA S
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Your health depends on the effective functioning
of your interdependent organ systems.
Do you think these people are experiencing stress?
physical
mental
If you have ever experienced any kind of stress, you
would know from your natural response to it that your
organ systems work together as a whole. In other words,
your organ systems are interdependent. For example, one
of the immediate effects of stress is that your muscles
become tense. This can trigger the heart, part of your
circulatory system, to beat faster, so it pumps blood more
quickly to the surface of the skin. As a result, you feel
warmer or even flushed. Tense muscles over a period
of time can also lead to aches, pains, and exhaustion.
Scientists have collected much experimental evidence
that your reaction to stress affects your health in many
ways. Some forms of stress, such as doing something
exciting or trying out a new game, can be fun and
thrilling. This stress can help prepare your body to
perform at its best. Other forms of stress can be
unpleasant, such as being nervous in new surroundings
or situations. Your reaction to stress can cause nausea
or stomach pain, or result in emotional problems.
Interdependence of systems is viewed in a broader
way in Indigenous Knowledge. Good health is when
your mind, heart, body, and spirit are in balance
(mental, emotional, physical, and spiritual harmony).
See Elder Velma Goodfeather’s message on page 58.
t io
emo nal
01-SK8-Unit1C
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3.1 A Look Inside
How do you feel when you are tense? What about when you are
relaxed? What are the physical, mental, emotional, and spiritual
effects when you feel tense or relaxed? Try the exercises on the
next page to find out.
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The medicine wheel indicates the
connections and interactions
between mental, emotional, physical,
and spiritual aspects of a person’s
being. There are many ways of
representing the medicine wheel.
Unit 1 Cells, Tissues, Organs, and Systems
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A
䉴
Sit so that you feel
comfortable. Close your
eyes and breathe slowly
and rhythmically. Focus
your attention on the
sound of your breathing.
Now, curl the toes of your
left foot as tightly as
you can. Hold for 3 s,
then slowly let them relax.
Slowly draw your foot
upward, hold for three
seconds, and then let it
down to the floor again.
Keep breathing slowly.
Now, repeat this with
your right foot.
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Push your belly out as
far as you can, and hold
for 3 s. Pull it in as far
as you can, hold for 3 s,
then relax. Take slow,
rhythmical breaths. Pull
your shoulders up toward
your ears as if you were
shrugging. Hold for
3 s, then relax. Keep
breathing slowly.
B䉱
Tighten the muscles in your left leg and hold for 3 s.
Then, relax your leg. Keep breathing slowly. Repeat
this with your right leg.
D 䉱
Clench your left hand in a tight fist, hold for 3 s, then relax.
Stretch your fingers apart as far as you can, hold for 3 s,
then relax. Repeat with your right hand.
E
䉴
䉴
Push your lips out and squeeze
your eyes shut as tightly as you
can. Hold for 3 s, then relax.
Open your eyes and mouth as
wide as you can—as if you
were screaming silently.
Hold for 3 s, then relax.
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3.0 Your health depends on the effective functioning of your interdependent organ systems.
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LOP
How Your Body Is Organized
Many parts of your body were involved in the exercises you just
completed. These included your skin, your bones, your heart,
your lungs, your mouth, and your stomach. What other examples
can you think of? Think back to Health Education and Science
classes that you did in earlier years. When scientists investigate
how your body works, they find that none of your body parts
functions on its own. Each part is an organ, a particular
arrangement of tissues that has a special function. A group of
organs form a body system, called an organ system. The organs
that make up each organ system work together to perform a
certain task or function.
Scientific studies allow a complex function to be broken
down into the simpler workings of its parts. Each part must
work well for the function to work well. For example, when you
eat an apple, the organs of your digestive system work together
to break down the food to supply your body with the energy
and nutrients you need to survive. Afterward, your digestive
system helps your body remove any unused material as waste.
The digestive process allows the cells in your body to get the
energy they need and eliminates harmful waste materials. The
following tables describe some of your body’s organ systems.
heart
Circulatory System
Structures
Function
Factors That Help Functioning
heart,
blood,
arteries,
veins
• transport oxygen, food, and
other substances throughout
the body
• transport some wastes to other
organs for elimination
• defend the body against
diseases
• connect all other organ systems
• arteries that are clear of
cholesterol
• exercise
Circulatory System
Red blood cells
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arteries = red
veins = blue
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Respiratory System
nose
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Structures
Function
Factors That Help Functioning
nose,
mouth,
trachea,
bronchi,
lungs
• transport oxygen from the
outside air to the blood
• transport carbon dioxide from
the blood to the outside air
• keep structures clear of harmful
pollutants (such as
tar from cigarette smoke)
• keep free from colds
mouth
trachea
lungs
bronchi
Digestive System
mouth
Structures
Function
Factors That Help Functioning
mouth,
esophagus,
stomach,
liver,
intestines
• break down food pieces into
much smaller pieces (particles)
so they can be absorbed and
transported throughout the body
• remove unused materials from
food out of the body as waste
• balanced diet
• water
esophagus
liver
stomach
intestines
The digestion of food begins in your mouth.
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Nervous System
Structures
brain
Function
Factors That Help Functioning
brain,
• co-ordinate and control the
spinal cord,
actions of all organs and
eyes,
organ systems
ears, and other
• detect, process, and respond
sense organs
to changes in external and
(hand, nose, etc.)
internal environment
• enough rest
• no stimulants or depressants
spinal cord
nerve
The brain controls your nervous system.
Excretory System
kidney
Structures
Function
Factors That Help Functioning
kidneys,
bladder,
lungs,
skin
• remove chemical and gaseous
wastes from the blood
• water
• balanced diet
kidney
bladder
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Working Together for Health
info BIT
A Close Association
Most people know that drinking
alcohol when you are pregnant
can harm your baby. But do you
know why this happens? When
a pregnant woman has an
alcoholic drink, the alcohol
passes from the mother into
the unborn baby’s (fetus’s)
bloodstream. Once inside the
fetus, the alcohol can damage
or destroy developing cells,
including brain and spinal
cord cells. The effects of this
damage can include birth
defects such as odd facial
features, growth problems, and
learning and behaviour problems.
All your organ systems work together as a single unit for a common
purpose: to support and maintain your life. This idea of working
together as a unified, purposeful unit goes even deeper than
systems. Each of your body’s systems contains organs. The organs
that make up each system work together to perform a certain task
or function. For example, the organs that make up your respiratory
system work together to provide your body with the oxygen it
needs, while ridding it of carbon dioxide. All of your organs support
and maintain the healthy functioning of the system of which they
are a part. The organs work in harmony for a healthy system.
As you already learned, there are four types of tissues in
humans and each human organ is made up of a group of tissues
that work together. For example, your heart is made up of
connective tissue (to hold its shape together), muscle tissue (to
help it to move), and nerve tissue (to co-ordinate its movement).
Different organs are composed of different kinds and amounts of
tissues. It all depends on the role (or function) that the organ serves.
Examples in animals
Examples in plants
Cells are the building
blocks of all organisms.
Tissues are clumps of
similar cells working
together in the same way.
Organs are groups of
tissues working together.
brain
shoot system
cell = an
individual
unit of life
tissue =
a group of
specialized
cells
organ =
a group of
tissues that
perform a
special
function
Body systems are made up of these
three types of structures.
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Systems are groups of
organs working together.
nervous
system
nerves
root
system
Cells form tissues, which form organs.
Every tissue in your body is made up of a group of smaller units,
the cells. These cells work together for a particular function and
each kind of cell suits its role in the body. For instance, muscle
cells can stretch and snap back into shape. Cells are the smallest
known functioning units of life. That is why scientists say that
the cell is the most fundamental or basic unit of all living things.
3.0 Your health depends on the effective functioning of your interdependent organ systems.
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1
a) Which of your organ systems were you aware of during
the stress-relieving exercises you did at the beginning of
this section?
b) Which of your organ systems do you think were actually
involved during the exercises? Provide details to support
your answer.
2
Demonstrate understanding of the relationship among these
terms: organ system, organ, tissue, and cell. Use words,
diagrams, flow charts, or a combination of these to
communicate your ideas.
3
Re-examine the organ system diagrams on pages 45–47.
a) Does any one system seem to be more important than
any of the others? Explain your answer.
b) Do you think you could stay healthy if any of these systems
were damaged, diseased, or missing? Why or why not?
c) For one of the systems, suggest another factor that might
affect the way it functions.
d) What does the title “Working Together for Health” mean
to you?
3.2 Close-up of the Circulatory System
Following are some early ideas about the circulatory system and its
main organ, the heart. Today, after about 350 years of investigation,
we know that only one of these early ideas is accurate. One is
partially accurate. The rest have been shown to be incorrect.
Do you know, or can you figure out, which is which?
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