Year 9 Science • AC9S9U03 • Authored homework
Carbon Cycle and Earth Spheres
Represent the carbon cycle and explain how photosynthesis, respiration, combustion and decomposition move carbon between the atmosphere, biosphere, hydrosphere and geosphere. Use topic vocabulary, evidence and clear cause-and-effect reasoning in longer answers.
Part A
Short-answer questions
Name the four Earth spheres involved in the carbon cycle.
Which process removes carbon dioxide from the atmosphere and stores carbon in plants?
Which process releases carbon dioxide when living things use glucose for energy?
Explain how combustion moves carbon into the atmosphere.
What is decomposition, and how does it affect carbon movement?
Give one example of carbon stored in the geosphere.
Explain how the ocean can be part of the carbon cycle.
What is the difference between a carbon store and a carbon transfer?
Write one word equation connected to the carbon cycle.
Correct this misconception: “Carbon is only found in the atmosphere.”
Part B
Long-answer questions
Draw or describe a carbon cycle diagram that includes photosynthesis, respiration, combustion and decomposition.
Explain how carbon moves from the atmosphere into plants, then into animals, then back to the atmosphere.
Analyse how burning fossil fuels changes the rate of carbon transfer between the geosphere and atmosphere.
Compare photosynthesis and respiration in terms of reactants, products and carbon movement.
Explain how the biosphere and atmosphere interact during a forest fire and during forest regrowth.
Describe how carbon can move between the hydrosphere and atmosphere.
Evaluate the effect of deforestation on carbon stores and carbon transfers.
Use a cause-and-effect chain to explain how increased combustion can influence the carbon cycle.
Create a table that separates carbon stores from carbon transfer processes and justify each example.
Write a full explanation of how Earth’s spheres interact through the carbon cycle, using at least three named processes.
Part C
Research and understanding task
Research one real carbon-cycle issue such as fossil fuel combustion, reforestation, ocean carbon storage, bushfires or soil carbon. Explain the carbon stores, transfer processes and Earth spheres involved.