This document discusses the levels of organization in multicellular organisms from cells to organisms. Cells are specialized to perform specific functions and tissues are groups of cells that work together. Organs are made of tissues to perform closely related functions. Organ systems are groups of organs that work together to perform a specific function. There are 11 major organ systems that make up an organism and carry out all life functions. Cells are the basic building blocks and smallest level of organization.

1. Levels of OrganizationLevels of Organization
Cell SpecializationCell Specialization
InIn
Multicellular OrganismsMulticellular Organisms

2. Unicellular OrganismsUnicellular Organisms
One celledOne celled
Carries out all life functionsCarries out all life functions
ProkaryotesProkaryotes –– do not contain a nucleusdo not contain a nucleus
EukaryotesEukaryotes –– do contain a nucleusdo contain a nucleus

3. Multicellular OrganismsMulticellular Organisms
Made up of many types of cellsMade up of many types of cells
Cell specializationCell specialization
Cells in multicellular organisms areCells in multicellular organisms are
specialized to perform particular functionsspecialized to perform particular functions
within the organism.within the organism.

4. Levels of OrganizationLevels of Organization
The levels or organization:The levels or organization:
CellsCells
TissuesTissues
OrgansOrgans
Organ SystemOrgan System
OrganismOrganism

5. CellsCells
Make life possibleMake life possible
Specialization & interdependenceSpecialization & interdependence
Examples of Cell Types:Examples of Cell Types:
NerveNerve
MuscleMuscle
FatFat
SkinSkin
HairHair
BloodBlood

6. Nerve Cell
RBC’s
Fat Cells Epithelial Cells
WBC’s

7. TissuesTissues
Group of cells thatGroup of cells that
perform a particularperform a particular
function.function.
4 Types4 Types
MuscleMuscle
EpithelialEpithelial
NervousNervous
ConnectiveConnective

8. OrgansOrgans
Group of tissues thatGroup of tissues that
work together towork together to
perform closely relatedperform closely related
functions.functions.
BrainBrain
HeartHeart
BonesBones
StomachStomach
LiverLiver
Kidneys, etc.Kidneys, etc.

9. Organ SystemOrgan System
Groups of organs thatGroups of organs that
work together towork together to
perform a specificperform a specific
function.function.
11 major organ systems.11 major organ systems.

10. OrganismsOrganisms
Can be unicellular orCan be unicellular or
multicellular.multicellular.
Must carry out lifeMust carry out life
functions to survive.functions to survive.

11. Let’s OrganizeLet’s Organize
Can you organize? Try and see!Can you organize? Try and see!
Place the appropriate words in the correctPlace the appropriate words in the correct
orderorder
Organ system cell tissue
Smallest Largest

13. To Sum UpTo Sum Up
Cells are specialized in order to have aCells are specialized in order to have a
functioning organism.functioning organism.
All cells contain the same basic biochemistry.All cells contain the same basic biochemistry.
Cells are the basic building block of all livingCells are the basic building block of all living
things.things.
Cells are essential to life as we know it.Cells are essential to life as we know it.

14. ““Help Wanted”Help Wanted”
Your group will create a help wanted ad forYour group will create a help wanted ad for
the specific Human Body system you chose.the specific Human Body system you chose.
Provide the followingProvide the following
Organs in the systemOrgans in the system
Tissues, and cells to create these organs andTissues, and cells to create these organs and
systemsystem
If you know the cells, provide a pictureIf you know the cells, provide a picture
GET AS CREATIVE AS YOU LIKE!!GET AS CREATIVE AS YOU LIKE!!