This document outlines the levels of biological organization from cells to the biosphere. It begins by describing unicellular and multicellular organisms and the differences between cells, tissues, organs, organ systems, and organisms. It then defines each level in more detail, from cells as the basic unit of life, to tissues as groups of the same cell type, organs as structures made of multiple tissue types, organ systems as groups of organs that work together, organisms as the whole entity, populations as groups of the same species, communities as multiple interacting populations, ecosystems as organisms and their environment, biomes as large climate-defined areas, and finally the biosphere as the portion of Earth that supports life.

1. TODAYS PLAN
• Describe unicellular and multicellular
organisms.
• Identify/Describe cell, tissue, organ, organ
system, and organism.
• Distinguish between the differences among cells,
tissues, organs, organ systems, and organisms.
TODAYS DO
• We will watch a short video about and discuss
the levels of cellular organization

2. TISSUE C
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ORGAN
ORGAN SYSTEM
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POPULATION
ECOSYSTEM
COMMUNITY

3. Who does it?

4. Division of Labor &
The First Level
Within living things, there are divisions of labor.
Division of labor means that the work (labor) of
keeping the organism alive is divided (division)
among different parts.
Each part has a job to do and as each part does its
special job, it works in harmony with all the other
parts. THE JOB OF THE SMALLEST THING
BUILDS ONT THE NEXT LEVEL!

6. Just like stair steps…
There are different LEVELS to
how one living thing is made, as
well as where it fits into this
world.
The arrangement of specialized parts within a living
thing is sometimes referred to as levels of organization.
We will discuss the levels from least
complex to most complex!

7. Levels of
Organization
studied in
BIOLOGY
…

8. How is life characterized within
these levels?

9. Life is organized into different levels
based upon size (from small to large).

10. Organisms and Cells
• Some organisms are unicellular.
– This means they are made of only one cell.
– Examples: bacteria, yeast
• Some organisms are multicellular.
– This means they are made of many cells.
– Examples: humans, trees

11. Organisms and Cells
• Unicellular organisms have nothing but a
single cell.
• However, multicellular organisms have
many more levels of organization to make
sure the whole body can work correctly,
even when it is doing many things at the
same time.

12. There are 9 Levels of Biological
Organization :
• 1. Cells
• 2. Tissues
• 3. Organs
• 4. Organ Systems
• 5. Organisms
• 6. Population
• 7. Community
• 8. Ecosystem
• 9. Biosphere

14. The cell is the basic
unit of life.
Cells are specialized by
size and shape for the
job they do.
The paramecium above is
made of only one cell and it
must perform all the jobs of
the organism.
Example: skin cell

15. T I S S U E S
Tissues are made of the same type of cells
grouped together to do a specific job.
Example: Humans have four kinds of tissue in their
Bodies: Epithelia, Muscle, Connective, and Nerve.

16. Organs
Organs are made up of different tissues
that work together to do a job.
Example: a heart
is an organ .

17. • Heart- pumping organ of the body
• Liver- detoxification, synthesis and
storage
• recovers and eliminates many
toxins.

18. • Kidney- remove waste products and
excess fluid from the body.
• Lungs- role is to bring in air from
the atmosphere and pass oxygen
into the bloodstream ( exchange of
gases)

19. • Brain-is an organ that serves as the center
of the nervous system in all vertebrate and
most invertebrate animals.
• Stomach
1.Temporary storage for food
2.Mixing and breakdown of food
3.Digestion of food

20. Organ Systems
An organ system is a group of
organs working together.
Examples:
•Human organ systems include circulatory,
reproductive, digestive, nervous, respiratory.
• Plant organ system-roots, stems, leaves=
transport system.

21. Organ System
• Cardiovascular / circulatory
transports nutrients and wastes
• Respiratory exchanges gases
• Immune protects against infection
• Digestive breaks down and absorbs
food

22. • Endocrine regulates metabolism and
produces hormones
maintains homeostasis
• Reproductive- produces gametes
Egg / sperm
• Excretory filters wastes
• Nervous receives stimuli and responds
• Skeletal System- Framework of the body

24. Organisms
All cells, tissues, organs and organ systems
working together makes an organism.
Example: a human

25. …to the largest level.
9.Population
Groups of individuals of the
same species that live in the
same area.
10. Community
Groups different populations that
live together in a defined area.
11.Ecosystem
Groups of all the organisms
that live in a particular place,
together with their nonliving
environment.
13. Biosphere
Part of the Earth in which life exists including
land, water, air and atmosphere.
12. Biome
Groups of ecosystems that
have the same climate and
similar dominant
communities