Energy Flow: Autotrophs

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Energy FlowAutotrophs

• Sunlight is the main source of energy for life
  on Earth.
• Autotrophs (also known as producers) have
  chlorophyll that captures the energy that allows
  a plant to assemble glucose during
  photosynthesis.

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Energy FlowAutotrophs

• The best know autotrophs are those that use the
  power of the sun to create glucose through
  photosynthesis.
• The second type of autotrophs use chemical energy
  to make glucose. This is performed by several
  types of bacteria.
• Autotrophs are the foundation of all ecosystems
  because they make energy available to all other
  organisms on earth that are not capable of
  photosynthesis.

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Energy FlowHeterotrophs

• Heterotrophs (also known as consumers) consume
  other organisms for their energy and food.

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Types of Heterotrophs

• Herbivores obtain energy by eating plants.
• Example Cow, rabbit, caterpillars
• Carnivores eat animals.
• Example Wolves, lions, owls
• Omnivores eat both plants
• and animals.
• Example Bears, humans

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Types of Heterotrophs

• Detritivores feed on the remains of dead plants
  animals and break the remains down to simple
  nutrients so that other organisms can consume
  them.
• Example Worms, aquatic insects
• Decomposers a type of detritivores, they break
  down dead remains by releasing digestive enzymes
• Example Fungi, bacteria

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Feeding Relationships

• Energy flows through an ecosystem in one
  direction, from the sun or inorganic compounds to
  autotrophs (producers) and then to various
  heterotrophs (consumers).
• Food Chains are a series of steps in which
  organisms transfer energy by eating or being
  eaten.
• Food webs more complex than a food chain, they
  show interactions within an ecosystem.

Food Chain
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Feeding Relationships

• Each step in a food chain or web is called a
  trophic level. Producers make up the first step,
  consumers make up the higher levels.

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Food Chain Arrows point toward the consumers

• What is the producer in the food chain?
• What is the primary (1st) level consumer?
• What is the secondary (2nd) level consumer?
• What is the tertiary (3rd) level consumer?
• What is the quaternary (4th) level consumer?

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Food Web

• Is the frog an herbivore or and omnivore?
• Is the snake a carnivore or an omnivore?
• What trophic level is the squirrel?
• Which carnivore consumes the mouse?

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Ecological Pyramids

• An ecological pyramid is a diagram that shows the
  relationship amounts of energy or matter
  contained within each trophic level in a food web
  or food chain.

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Ecological Pyramids

• Energy Pyramid only 10 of the energy available
  within one trophic level is transferred to
  organisms at the next trophic level.

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Ecological Pyramids

• Pyramid of Numbers show the relative number of
  organisms at each trophic level. As the pyramid
  moves up the trophic levels the number of
  organisms decrease because there is less energy
  available to support the organisms