Characteristics of Life
What makes a living thing a living
thing?
Organism
• An organism is an individual living thing
• It’s an independent unit of life.
• If you lop off your arm, it is made of living
materials.
• However, it is not a living thing because it
cannot sustain itself.
1. Cellular Organization
• All living things are
made of cells
• Unicellular organisms
are single-celled
organisms.
• Multi-cellular organisms
are made of more than
one cell
2. Chemicals of Life
• It doesn’t matter if you’re an amoeba or an
aardvark.
• All living things have a similar chemical
makeup.
• They all have water in them.
• They all have the 4 organic molecules:
–
–
–
–
Carbohydrates
Proteins
Lipids
Nucleic Acids (DNA)
3. Use energy
• All living things use
energy to sustain life
• Heterotrophs- get their
energy from eating
other living things
• Autotrophs- make their
own food using energy
from the Sun.
4. Growth and Development
• Organisms usually increase in size
• Organisms become more complex
5. All living things respond to
their environment
• Stimulus- a change that
causes an organism to
react
• Living things respond to
the stimuli around them
• The doorbell rings…
• The bell rings…
• You hear a fire alarm…
6. Reproduction
• One living thing must
come from another
living thing like it
• Asexual- only one
organism is needed
• Sexual- two organisms
are needed to
reproduce
7. Living things adapt and evolve
• Living things can
change over many
generations.
• Natural SelectionOrganisms that are best
suited to their
environment will survive
8. Homeostasis
• All living things must
maintain a stable
internal environment.
Exit Quiz
1. Give an example of a stimulus and a
reaction.
2. Why do animals adapt over time?
3. What is the difference between growth and
development?
Which feature of life is this
an example of?
Living Things Need Food!
Can You Identify the Feature
Shown in the Pictures Below?
• Living Things Develop!
What Feature of Life is Shown
Below?
• Living Things Respond To Their Environment!
What Feature Do You See
Here?
• Living Things Are Adapted to Their
Environment!
What Feature Is Shown
Below?
•
Living Things Reproduce!
What Feature is This?
• Living Things Grow!
• Living Things Develop!
Which Feature of Life Do We
Have Here?
• Living Things Use Energy!
• Living Things Need Food!
Finally, What Feature of Life is
This?
• Living Things Are Made of Cells!