3.3 - Recycling Matter in Ecosystems

• • Matter is constantly being recycled through the biosphere - remember, energy is not and instead flows and is "used up" in organisms
• The Carbon Cycle moves carbon through:

  • the atmosphere
  • living organisms
  • the earth
• • Producers
  • take in carbon dioxide (CO2) & water
  • Releases oxygen (O2)
  • Makes glucose through photosynthesis!
• • Heterotrophs & Autotrophs
  • Take in oxygen (O2) AND eat/make food which has carbon in it in the form of glucose
  • Release carbon dioxide through cellular respiration in the "mighty mitochondria" of cells
• • Carbon is also released through:
  • feces
  • decomposition -> decaying dead organism release it into soil
  • combustion -> burning fossil fuels/fires, volcanoes
• The Nitrogen Cycle

  • Organisms need nitrogen to make nucleic acid (DNA) & proteins (enzymes & muscle)
  • some bacteria can take nitrogen from the air and change it into compounds in the soil
  • These bacteria can live in soil and roots some plants called legumes
  • Ex: clover, peas, beans, alfalfa
  • Plants take in the nitrogen from the soil through roots and can pass it onto animals when eaten
  • Nitrogen from dead & decaying organisms & waste also goes back into the soil
  • Humans can add nitrogen to soil by putting fertilizers in the soil
• • Nitrogen Fixation: the process of taking nitrogen in the air and changing it into a form that plants and animals can use