Levels of Organization
• What do you think the 5 Levels of
Organization are in the body??
• Brainstorm with your group and write down
what you think are the 5 Levels – Pick a
recorder.
Levels of Organization:The arrangement of specialized
parts within a living thing.
The labor (work) is divided
among 5 different levels.
What is Division of Labor??
Division of Labor
Within multi-cellular organisms there is
Division of labor.
Division of labor - 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.
1st Level - Cells
• Cells are the basic
unit of living
things.
• They are very
diverse and all parts
of the cell perform
specific functions.
Plant Cell
Animal Cell
Cells: LOTS of Different Kinds!Here are two examples. Can you guess what kind?
Nerve Cells Skin Cells
Second Level: Tissues
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.
In any multi-cellular organism, cells rarely work alone.
Tissues are the second level
Tissues are Cells that are similar in structure and function and
are usually joined together to form tissues.
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.
Taken One At A Time….Connective tissue connects
& supports parts of the
body- examples: Blood, fat,
ligaments, cartilage, bones,
tendons
Nerve tissue carries messages
back & forth between brain &
other parts of body. Examples:
brain, spinal cord,& nerves
Epithelial tissue covers & lines
body surfaces & organs, inside &
out. Provides a protective barrier.
Example: skin
Muscle tissue contracts, or
shortens - makes parts of your
body move.
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????
Level Four: Organ Systems
Each organ in your body is
part of an organ system
organ system, group
organs working together to
perform a major function.
For example, your heart is
part of your circulatory
system, which carries oxygen
& other materials throughout
the body. Besides the heart,
blood vessels are organs that
work in your circulatory
system.
nervous system detects &
interprets info from
environment outside & within
body; controls most body
functions.
immune system: fights
disease.
excretory system: removes
wastes.
endocrine system: controls
body processes by means of
chemicals, like hormones.
Muscular system: enables body
to move; moves food through the
digestive system, and keeps the
heart beating.
Skeletal system: supports and
protects body, and works with
the muscular system to allow
movement; makes and stores
blood cells and stores some other
materials.
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.
Level 5 – Organisms -
All other levels form together to
make organisms
• Entire living things that can carry out all basic life processes.
• Protists
• Plants
• Animals
• Humans
Let’s Review….
• 1st Level: Cells
working together form
• 4th Level: Organ Systems,
which work
together to form
• 2nd Level: Tissues,
which can form• 3rd Level: Organs,
which work
together to form
• 5th Level: Organisms!