UGC NET Questions (Paper – 1)

Unlike carbon and nitrogen, which have major gaseous components in the atmosphere, phosphorus moves primarily through rocks, soils, water and organisms. Weathering of rocks releases phosphate into soils and water bodies, where it is taken up by plants and moves through food webs. Over long time scales, it returns to sediments and rocks. This dominance of solid and aqueous phases and the absence of a substantial atmospheric form make the phosphorus cycle largely sedimentary, as indicated in Option B.

Option A:
Option A is incorrect because phosphorus does not have a large atmospheric gaseous phase. Nitrogen and carbon dioxide are prominent atmospheric gases, but phosphorus compounds are not abundant in the air.

Option B:
Option B is correct since it highlights the key difference that phosphorus cycles mostly between land, water and biota without a major gaseous reservoir. This characteristic contributes to phosphorus often being a limiting nutrient in ecosystems.

Option C:
Option C is incorrect because rocks and sediments are central to the long-term phosphorus cycle. Ignoring them misrepresents how phosphorus is stored and released.

Option D:
Option D is incorrect; phosphorus cycles both on land and in aquatic systems. Terrestrial soils and freshwater bodies are important components of its global cycle.