Transcript Levels of Organization

Levels of Organization
Multicellular Organisms:
I. First Level: Cells
Cells are the first level or simplest level
of organization.
Cells: LOTS of Different Kinds!
Nerve Cells
Skin Cells
II. Second Level: Tissues
A. Cells that are similar in structure and function
are usually joined together to form tissues.
B. There are four basic/major types of tissues in
the human body: Muscle tissue, nerve tissue, connective
tissue, and protective tissue.
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 protective
tissue.
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.
Protective 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.
III. Level Three: Organs
A. When 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??
IV.Level Four: Organ Systems
A. Each organ in your body is
part of an organ system, a
group of organs that work
together to perform a major
function. There are 11 body
systems.
1. For example, your heart is
part of your circulatory
system, which carries oxygen
and other materials
throughout your body.
2. The nervous system detects
and interprets information from
the environment outside the body
and from within the body;
controls most body functions.
3. The immune system fights
disease.
4. The excretory system
removes wastes.
5. The endocrine system
controls many body processes
by means of chemicals, like
hormones.
6. The muscular system enables
the body to move; moves food
through the digestive system, and
keeps the heart beating.
7. 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.
8. The digestive system takes
food into the body, breaks the
food down into smaller particles,
and absorbs the digested
materials.
9. The respiratory system
takes oxygen into the body and
eliminates carbon dioxide.
10. The reproductive system
produces sex cells that can
unite with other sex cells to
create offspring; controls male
and female characteristics.
10. The integumentary
(skin) is the organ system
that protects the body from
damage, comprising the
skin and its appendages
(including hair, and nails.)
V. Organism
A. A Living thing. It can perform life
processes on its own. It is the most complex
level of organization
B. Examples: Cat, Human,
Bacteria, Virus, Tree
Let’s 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: Living Things