1. Learning Goal #1: Summarize how energy flows through an ecosystem.
Unit 1: Ecology
Learning Goal #1: Summarize how energy flows through an ecosystem.

2. Energy Flow
At the core of every organism’s interaction with the environment is its need for energy to power life’s processes.

3. Energy Flow Energy in must EQUEAL Energy out What is energy used for?
How do organisms gain energy?
Energy in must EQUEAL Energy out

4. Producers Sunlight is the main energy source for life on Earth.
Only 1% of the sun’s energy that reaches the Earth is used by living things.
Some types of organisms rely on the energy stored in inorganic chemical
compounds.
Mineral water flows underground
or boils out of hot springs and
undersea vents loaded with
chemical energy.

5. Autotrophs
Organisms that capture energy from sunlight or chemicals and use that energy to produce food.
Plants, some algae, and certain bacteria.
Use the energy to take simple inorganic molecules and make complex organic molecules.
Also called producers.
They make their own food.

6. Photosynthesis
Autotrophs use light energy to power chemical reactions that convert carbon dioxide and water into oxygen and energy-rich carbohydrates such as sugars and starches.

7. Chemosynthesis Organisms use chemical energy to produce carbohydrates.
They use the chemical energy stored in chemical bonds.
This can be done in the absence of light.

8. Consumers
Organisms that rely on other organisms for their energy and food supply.
Also called heterotrophs.
Herbivores: Eat only plants.
Carnivores: Eat only animals
Omnivores: Eat both plants and animals.
Detritivores: Feed on plant and animal remains and other dead matter.
Decomposers: Break down organic matter.

9. Feeding Relationships
Energy flows through an ecosystem in one direction, from the sun or inorganic compounds to autotrophs and then to various heterotrophs.

10. Food Chain
A series of steps in which an organisms transfer energy by eating and being eaten.

11. Food Web A food web links all the food chain in an ecosystem together.

12. Trophic levels Each step in a food web or food chain.
Producers make up the 1st trophic level.
Consumers make up the 2nd, 3rd or higher trophic levels.
Consumers depend on the levels below them for energy.

13. Ecological Pyramids
A diagram that shows the relative amounts of energy or matter contained within a trophic level in a food chain or food web.

14. Energy Pyramid
Only about 10 % of the energy available within one trophic level is transferred to organisms at the next trophic level.

15. Biomass Pyramid
Biomass is the total amount of living tissue within a given trophic level.
A biomass pyramid represents the amount of potential food available for each trophic level in an ecosystem.