Carbon cycle

• Carbon cycle


  The process by which carbon is continuously cycled through the environment
• Carbon cycle


  • Starts with carbon dioxide in the atmosphere
  • Carbon can only enter the cycle through photosynthesis
• Photosynthesis


  1. Carbon dioxide combines with water to make glucose

  2. Uses light energy

  3. Carried out by plants
• Respiration


  1. Returns carbon dioxide to the atmosphere

  2. Carried out by all living organisms
• Photosynthesis


  Adds carbon to the cycle
• Respiration


  Removes carbon from the cycle
• Carbon cycle


  1. Plants and algae take in carbon dioxide from atmosphere

  2. Carbon becomes part of carbohydrates, fats and proteins in plants and algae

  3. Plants and algae respire, releasing some carbon dioxide

  4. Plants and algae eaten by animals, carbon becomes part of animal cells

  5. Animals respire, releasing some carbon dioxide

  6. Animals release waste and die

  7. Decomposers break down waste and dead remains, releasing carbon dioxide

  8. Under certain conditions, carbon in dead remains can be converted to fossil fuels
• Decomposers are extremely important as they cycle materials through an ecosystem and return carbon to the atmosphere as carbon dioxide
• Decomposers also release mineral ions to the soil
• If decomposers cannot function effectively due to lack of oxygen, carbon in dead remains can slowly be converted to fossil fuels
• Over the last 200 years, humans have been burning huge amounts of fossil fuels, releasing a large amount of carbon dioxide back to the atmosphere