1. Energy Flow in Ecosystems

2. All Organisms Need Energy To Survive!
Some organisms get energy by making it themselves
These organisms are called autotrophs

3. All Organisms Need Energy To Survive!
Some organisms get energy from other organisms
These organisms are called heterotrophs

4. Autotrophs Another word for autotroph is producer
Examples of autotrophs include grass, algae and trees
Autotrophs make their own energy (food) by using the sun’s energy to convert water and carbon dioxide into a form of food that they can use called glucose
This process is called photosynthesis

5. What Happens to all the Energy Made by Autotrophs/Producers?
They use most of it to carry out their functions (growing, reproducing, etc.)
Some of it is lost in the atmosphere as heat
Only 10% of the energy is available for the organisms that eat them

6. Heterotrophs Another word for heterotroph is consumer
Examples of heterotrophs include dogs, fish, elephants, and mushrooms
Heterotrophs get their energy by consuming/eating other organisms
There are many different types of heterotrophs/consumers…

7. Heterotrophs Primary Consumers only eat plants (herbivores)
Secondary Consumers eat primary consumers (carnivores/omnivores)
Tertiary Consumers eat secondary consumers (carnivores/omnivores)
Scavengers feed off of dead consumers
Decomposers feed by breaking down organic matter from dead organisms

8. What Happens to all the Energy Consumed by Heterotrophs?
They use most of it to carry out their functions (growing, reproducing, etc.)
Some of it is lost in the atmosphere as heat
Only 10% of the energy is available for the organisms that eats them

9. Food Chains
Food chains show the transfer of energy from the sun to producer to consumer
Arrows point in the direction that the energy is going 9

10. Food Webs
Very rarely in nature is the transfer of energy in an ecosystem as simple as a single food chain
Food webs are interconnected food chains that show feeding relationships of many organisms in an ecosystem 10

11. Food Webs 11

12. Energy Pyramids
An energy pyramid is yet another way of showing the transfer of energy in an ecosystem
Each level is called a trophic level
They also show
How amount of available energy decreases for higher consumers
That it takes a large number of producers to support a small number of tertiary consumers

13. Energy Pyramids