Levels of Organization

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Levels of Organization

• Mrs. McCabe
• 04/08
• Adapted from Joe Krupens, Standley Middle School

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Division of Labor The First Level
Within multi-cellular organisms there is
division of labor. Division of labor means that
the work (labor) of keeping the organism alive is
divided (division) among the different parts of
the body. Each part has a job to do and as each
part does its special job, it works in harmony
with all the other parts.
The arrangement of specialized parts within a
living thing is sometimes referred to as levels
of organization. Cells of course, are the first
level of organization.
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Cells LOTS of Different Kinds!Here are two
examples. Can you guess what kind?
Nerve Cells
Skin Cells
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Second Level Tissues
In any multi-cellular organism, cells rarely work
alone. Cells that are similar in structure and
function are usually joined together to form
tissues. Tissues are the second level of
organization.
There are four basic/major types of tissues in
the human body Muscle tissue, nerve tissue,
connective tissue, and epithelial tissue. (There
are other kinds of tissues besides these.) Other
kinds of tissue include bone tissue (a strong
solid tissue that gives you shape and support)
made of bone cells in your body form bone tissue.
Blood cells in your body are part of blood
tissue, a liquid tissue responsible for
transporting food and oxygen throughout the body.
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Lets Look Again
Here are the cells we saw before, but if you look
closely, you can see that they all look similar.
Nerve cells working together make nerve tissue,
and skin cells make up a special type of
epithelial tissue.
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Taken One At A Time.
Connective tissue connects and supports parts of
the body. Blood, fat, ligaments, cartilage,
bones, and tendons are all connective tissues.
Nerve tissue carries messages back and forth
between the brain and every other part of the
body. The brain, spinal cord, and nerves are made
up of nerve tissue.
Epithelial tissue covers and lines the surfaces
of your body and organs, inside and out. They
primarily serve as protective barriers. Skin is
one example.
Muscle tissue can contract, or shorten. Because
of this, muscle tissue makes parts of your body
move.
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Level Three OrgansWhen a bunch of different
types of tissues work together, they form an
organ. There are many organs in the body. How
many can you name??
GET IT????
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Level Four Organ Systems
Each organ in your body is part of an organ
system, a group of organs that work together to
perform a major function.
For example, your heart is part of your
circulatory system, which carries oxygen and
other materials throughout your body. Besides the
heart, blood vessels are organs that work in your
circulatory system.
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The nervous system detects and interprets
information from the environment outside the body
and from within the body controls most body
functions.
The immune system fights disease.
The excretory system removes wastes.
The endocrine system controls many body processes
by means of chemicals, like hormones.
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The muscular system enables the body to move
moves food through the digestive system, and
keeps the heart beating.
The skeletal system supports and protects the
body, and works with the muscular system to allow
movement makes and stores blood cells and stores
some other materials.
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The digestive system takes food into the body,
breaks the food down into smaller particles, and
absorbs the digested materials.
The respiratory system takes oxygen into the body
and eliminates carbon dioxide.
The reproductive system produces sex cells that
can unite with other sex cells to create
offspring controls male and female
characteristics.
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Lets Review.

• 1st Level Cells working together form

• 2nd Level Tissues, which can form

• 3rd Level Organs, which work together to form

• 4th Level Organ Systems, which work
  together to form

• 5th Level Organisms!