Levels of Organization - Davis School · PDF fileLevels of Organization ... •Some...
Transcript of Levels of Organization - Davis School · PDF fileLevels of Organization ... •Some...
Levels of Organization
The arrangement of specialized parts within a
living thing:
• Cells
• Tissues
• Organs
• Organ Systems
• Organism
Division of Labor
-the work of keeping the organism alive is
divided 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.
Tissue Level-Many cells make up tissue
-In any multi-cellular organism, cells rarely work
alone.
-Cells that are similar in structure and function are
usually joined together to form tissues
Nerve Cells Skin Cells
Different types of tissues...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.
Let’s 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.
System Level
-Each organ in your body is part of an organ system, a group of organs that work
together to perform a major function.
-Many organs together make up a system
What system are the brain, spinal cord, and nerves?
For example, your
heart is part of your
circulatory system,
which carries oxygen
and other materials
throughout your body.
Besides the heart,
blood and blood
vessels are organs that
work in your
circulatory system.
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.
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.
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.
Organism Level
• Many systems together make up an
organism.
• Some organisms have only a few systems,
like sea sponges, while others have up to 11
systems like humans.
Let’s Review….• 1st Level: Cells when they work together
they form…
• 4th Level: Organ Systems, when they work
together they form an…
• 2nd Level: Tissues, when they work together
they form…
• 3rd Level: Organs, when they work together
they form…
• 5th Level: Organism!
Simple Organisms
• Uni-celled
• Don’t rely on any other cells to help them survive
• When they reproduce they just make more exactly
like themselves but not connected to each other.
Complex Organisms
•Many-celled organisms
•Have all levels of organization
•Rely on other levels for survival