Energy Flow in Ecosystems. All Organisms Need Energy To Survive! Some organisms get energy by making...

Energy Energy Flow in Flow in

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All Organisms Need Energy To Survive!

• Some organisms get energy by making it themselves

• These organisms are called autotrophs

All Organisms Need Energy To Survive!

• Some organisms get energy from other organisms

• These organisms are called heterotrophs

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

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

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…

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

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

Food Chains• Food chains show the transfer of energy

from the sun to producer to consumer

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• Arrows point in the direction that the energy is going

Food Webs

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• 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

Food Webs

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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

Energy Pyramids