BY4.5 Carbon and Nitrogen Cycles

Carbon Cycle

• CO2 is added to the atmosphere from:
  • repsiration of plants, animals and microorganisms
  • combustion of fossil fuels

• photosynthesis uses about as much CO2 as it releases

• production of carbs, fats and protein contains carbon which is needed for plant and animal growth
  • remains of dead animals are decomposed by saprophytes in the soil which release CO2

• accumulation of dead animals in aerobic coditions forms coal, oil and other fossil fuels
  • burning these releases CO2

Nitrogen Cycle

the flow of organic and inorganic nitrogen in an ecosystem wheree there is an interchange between nitrogenous componds and atmosperic nitrogen

ammonium ions taken up by the roots and are used for prowin synthesis, nuceic acid synthesis and amino acid production

• putrefaction:
  • bacteria and fungi…