Same chapter3 marksDifficulty: Medium
What is primary productivity? Distinguish between gross and net primary productivity.
Ecosystem
3 marksDifficulty: Medium
Describe the carbon cycle in outline.
Original Khojo Papers practice question — not from a past board paper.
Answer
Carbon enters living matter when producers fix atmospheric carbon dioxide by photosynthesis, and it passes along the food chain. It returns to the atmosphere through the respiration of producers, consumers and decomposers, and through the burning of wood and fossil fuels. A large reserve is held in the oceans, in fossil fuels and in sedimentary rock.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Human burning of fossil fuels has raised the atmospheric share of the cycle sharply.
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