1. The Characteristics of Living Things
Biologists use six characteristics to classify something as a living thing.
Made of cells
Composed of certain chemicals
Use energy
React to changes
Grow and develop
Reproduce

2. The Characteristics of Living Things
All living things have these six characteristics.
Anything without one of these six characteristics is nonliving.
Living things are called organisms.

3. 1. Cellular Organization
Organisms are made up of one or more cells.
A cell is the basic unit of structure and function in living things.
Cells = the
“Building Blocks"
of life.

4. 2. The Chemicals of Life
Cells are composed of certain important chemicals like:
Carbohydrates – main energy source
Proteins and lipids – building materials
Nucleic acids – genetic material

5. 3. Energy Use All organisms need and use energy to live.
Energy is the ability to do work.
Sunlight is the source of energy for most living things.
Plants use the energy in sunlight to make food, and animals get energy by eating plants or other animals that have eaten plants.

6. 4. Response to Surroundings
Organisms react to change in their surroundings.
Any reaction to change is called a response.
For example: A bright light may cause you to blink.

7. 5. Growth and Development
All organisms grow and develop.
Living things change, or develop, during their lifetimes.
One way organisms change is by growing.
Living things may also change in appearance.
For example: tadpoles and frogs

8. 6. Reproduction Organisms produce more organisms of their own kind.
Reproduction allows organisms to continue living on the earth.

9. Needs of Living Things All living things need four things to survive:
Water
Food
Living space
Stable internal conditions

10. 1. Water Helps organisms to: * Break down food * Grow
* Move substances within their bodies
* Reproduce

11. 2. Food Used to get energy for life functions
Autotrophs/Producers= plants
Heterotrophs/Consumers= most animals
* Carnivores- eat meat
* Herbivores- eat plants
* Omnivores- eat plants and animals

12. 3. Living Space Place where they can get food, water, find shelter
Organisms may compete for this space

13. 4. Stable internal conditions
Homeostasis- organisms need to maintain stable conditions inside their body
* Temperature
* Amount of water
Allows cells to function properly