I. Energy Flow

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I. Energy Flow

• A. Producers
• Make their own food through photosynthesis
• Examples Plants, algae

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• B. Consumers
• Feed on other organisms, cannot make their own
  food
• Example humans, bear, insects

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• C. Decomposers
• Break down dead organisms, recycle chemicals to
  soil, water, air
• Example fungi bacteria

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• D. Energy enters ecosystems as LIGHT is
  converted to CHEMICAL ENERGY by producers and
  exits the ecosystem as HEAT.

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II. Food Chain

• A. Trophic levels
• Feeding level
• Represents position in food
• chain/food web

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• B. Food Chain
• pathway of food transfer from one
• trophic level to another
• You always start with PRODUCERS on the
  left/bottom of a food chain.

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• C. Producer --gt Primary Consumer--gt
• Secondary Consumer--gt Tertiary Consumer
• D. Decomposers are found at EACH trophic level.

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III. Food Web

• A. Definition
• interconnected branching food chains- more
  realistic representation of feeding relationships

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IV. Three Kinds of Ecological Pyramids

• A. Energy pyramid
• Description diagram representing energy loss
  from one trophic level to the next

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10 Rule An average of 10 of the
available energy at a trophic level is converted
to biomass in the next higher trophic level.
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• B. Biomass Pyramid
• Description represents the dry mass of organisms
  at each trophic level

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• C. Pyramid of Numbers
• Description the number of individual organisms
  in each trophic level of an ecosystem

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• Why do you think all 3 pyramids look similar?