Environment & Ecology•CSE•2021•Q27
Nutrient cycling
Revise 3 earlier PYQs together to build the knowledge CSE 2021 Q27 tests.
Curated to help you revise related PYQs together and understand how UPSC revisits concepts across years — educational guidance, not a prediction.
The question this prepares you for · CSE 2021 · Q27
In case of which one of the following biogeochemical cycles, the weathering of rocks is the main source of release of nutrient to enter the cycle?
Carbon cycleNitrogen cyclePhosphorus cycleSulphur cycle
Why revise these together?
The target requires understanding that the phosphorus cycle is sedimentary, with rock weathering as the main nutrient source, and that carbon/nitrogen/sulphur cycles are largely gaseous. The carbon-cycle and nitrogen-cycle sources directly teach two of the four options as gaseous/atmospheric cycles, enabling elimination, and the supporting-services source reinforces nutrient cycling. Together they build the gaseous-vs-sedimentary contrast that cracks the question, even though phosphorus itself is absent.
Revise these earlier PYQs together
Related concepts
Biogeochemical cyclesNutrient cyclingCarbon cycleNitrogen cycle
Start a free 15-day trial to open every question, see the answers and explore the full pattern.
Start free trial