Flow of Matter and
Energy
A food chain is a linear representation of who eats
who in an ecosystem.
Quaternary Consumer
Tertiary Consumer
Secondary Consumer (carnivores or omnivores)
Primary Consumer (herbivores)
Producers (plants, algae)
If you die before being incorporated
into the food chain...
Scavengers
Detritus Feeders
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Decomposers
Food Webs

Food webs show the
interactions between
many food chains
Photosynthesis
Cell Respiration
Trophic Pyramid
Quaternary Consumers
10 kcal
Tertiary Consumers
100 kcal
Secondary Consumers
1000 kcal
Primary Consumers
10,000 kcal
Producers
100,000 kcal
Trophic Pyramid
As you move up a
trophic pyramid
 Energy decreases
 Number of individuals
decreases
 Biomass decreases (#
individuals times their
weight)
Trophic Pyramids and
Feeding a Starving Nation
Human Primary Consumers
10,000 kcal
Human Secondary Consumer
1000 kcal
Cow Primary Consumer
10,000 kcal
Producers
100,000 kcal
Producers
100,000 kcal
Bioaccumulation