Question

Explain with suitable diagram the path that carbon takes to go back to the atmosphere. You may start from plants using CO₂ from the atmosphere.

Answer 1

Atmospheric $$\mathrm{CO_2}$$ → [photosynthesis] → Plants → [eating] → Animals → [respiration/decomposition] → Atmospheric $$\mathrm{CO_2}$$; buried organic matter → Fossil fuels → [combustion] → Atmospheric $$\mathrm{CO_2}$$. Plants take in $$\mathrm{CO_2}$$ and fix carbon into glucose; respiration by plants/animals and decomposition of dead matter return it. Burning fossil fuels releases ancient stored carbon back to the atmosphere, completing the cycle.