ecology

• All organisms require energy; almost all of this comes from radiant energy
• Radiant energy absorption and conversion

  1. Absorbed by the hydrosphere and lithosphere

  2. Converted into thermal energy (heating and cooling)

  3. Warms the atmosphere

  4. Produces winds

  5. Evaporates water (some is reflected)
• A very small amount of radiant energy is used for photosynthesis but is very important for life
• Photosynthesis


  1. Sun's light energy is being converted into chemical energy (only occurs in producers)

  2. Glucose (sugar) is stored chemical energy in the leaves, stems, roots, and seeds of plants

  3. Carbon dioxide + water + sunlight -> glucose + oxygen
• Cellular Respiration


  1. Uses oxygen to release the chemical energy stored in sugar

  2. Glucose + oxygen -> carbon dioxide + water + energy
• Cellular Respiration


  • Complementary (opposite) process to photosynthesis
  • Occurs in all organisms (including plants)
• Ecology Pyramids


  Display relationships between trophic levels in ecosystems
• Types of Ecology Pyramids

  • Pyramid of Energy
  • Pyramid of Numbers
  • Pyramid of Biomass
• Energy lost and transferred is only 10% to the next trophic level in the Pyramid of Energy
• Pyramid of Numbers


  • Shows the number of organisms at each trophic level
• Pyramid of Biomass


  • Shows the amount of organic matter present at each trophic level
• Skull Features


  • Used to determine if an organism is a herbivore, omnivore, or carnivore
• Cellular respiration burns sugars for energy, releases energy, and occurs in most cells
• Photosynthesis produces sugars from energy, uses oxygen, and occurs only in cells with chloroplasts
• Biogeochemical Cycles


  Series of cycles in which chemicals are continuously consumed, rearranged, stored and used
• Major Nutrient Cycles


  • Water Cycle
  • Carbon Cycle
  • Nitrogen Cycle
• Water Cycle


  1. Evaporation-liquid water to vapour

  2. Condensation-water vapour forms water or ice crystals

  3. Precipitation-water or ice crystals return to Earth

  4. Surface runoff-water and melting snow/ice moves across land entering the watershed and groundwater

  5. Transpiration-water released from leaves
• Carbon Sinks


  Places where carbon is stored on Earth, including fossil fuels, limestone, plant tissue, and dissolved in oceans
• Natural Carbon Cycle


  1. Cellular respiration adds carbon dioxide to the atmosphere

  2. Photosynthesis removes carbon dioxide from the atmosphere

  3. Through the food chain and decomposition
• Human activities like burning fossil fuels and deforestation release excess carbon from carbon sinks, causing global climate change
• Nitrogen Cycle


  1. Most nitrogen is in the atmosphere

  2. Converted to useful form for living things through nitrogen fixing bacteria and lightning

  3. Nitrogen in soil is absorbed by producers, passed to consumers and up the food chain

  4. Bacteria return nitrogen to the atmosphere