Order the Levels of

Organization from Simple

to Complex

Levels of Organization

The arrangement of specialized parts within a

living thing:

• Cells

• Tissues

• Organs

• Organ Systems

• Organism

Division of Labor

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.

Cell Level

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.

Organ Level-tissues working together to perform a function make

up an organ.

Brain

There are many organs in the body.

How many can you name?

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!

What level are you?

Which level is simple ?

Which level is complex?

• Cell

• Tissue

• Organ

• System

• Organism

WHY?

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

Cell specialization…

…creates tissue, organ, and system level.

Simple or Complex?