nutrient cycling

Question 1

carbon cycle

Answer 1

• organic compounds in living consumers –> returns cO2 to the atmosphere -> Co2 in the air and dissolved in water e.g. the ocean-> removes Co2 from the envvironment-> organic compounds in green plants feed living consumers-> the plants/ animals die -> decay and decomposistion- Co2 released as microorganisms respire ->fossilisation -> carbon compounds in fossil fuels-> burning -> Co2 in the air and dissolved in water

Question 2

nutrient cycling

Answer 2

• carbohydrates, proteins, fats , DNA contain carbon
• photosynthesis, respiration, decay involve the transfer of carbon from one molecule to another
  Key sinks:- trees/plants- sea- sedimentary rocks- fossil fuels- biomass- soil