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9	Energy Flow in Ecosystems The Food Chain The producers = autotrophs Organisms that get energy straight from the abiotic environment (the sun) Example? The consumers = heterotrophs “Dependant” organisms that get energy from feeding on other organisms. They are incapable of producing their own food
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11	Energy Flow in Ecosystems The Food Chain Heterotroph’s display a variety of feeding relationships Herbivores aka primary (1°) consumers Eat producers Carnivores aka secondary (2°) consumers carnivores = predators... eat 1° consumers Scavengers eat animals that have already died Omnivores aka tertiary (3°) consumers Eat a variety of food: both plant and animal material Don’t forget the decomposers!
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13	Energy Flow A food chain is a simple model used to show how matter and energy move through an ecosystem Each organism in a food chain represents a feeding step, or trophic level, in the passage of energy Moves from autotrophs to heterotrophs & eventually to decomposers
14	Energy Flow Once energy enters a trophic level, it can either be used by that trophic level and is lost as heat be passed on to the next trophic level become detritus, going to the decomposers
15	Food Chains vs Food Webs Food chains are often too simplistic - real life is much more complicated An organism may occupy more than one trophic level A food web shows ALL the possible feeding relationships at each trophic level in a community
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17	10% Rule Only 10% of the energy from one trophic level is passed on to the next trophic level.
18	Energy Pyramid Each level in an energy pyramid represents the energy available to that trophic level
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