Minimalist IAS
Prelims 2022 paper

UPSC CSE Prelims 2022 · GS Paper I · Question 43 · Ecology & ecosystems

“यदि वर्षावन और उष्णकटिबंधीय वन पृथ्वी के फेफड़े हैं, तो निश्चित ही आर्द्रभूमियाँ इसके गुर्दों की…

UPSC Civil Services (Preliminary) Examination 2022, General Studies Paper I, Question 43 — Ecology & ecosystems.

Prelims 2022 · Q43

Ecology & ecosystems X-Ray · Core #41 Easy

“यदि वर्षावन और उष्णकटिबंधीय वन पृथ्वी के फेफड़े हैं, तो निश्चित ही आर्द्रभूमियाँ इसके गुर्दों की तरह काम करती हैं ।” निम्नलिखित में से आर्द्रभूमियों का कौन-सा एक कार्य उपर्युक्त कथन को सर्वोत्तम रूप से प्रतिबिंबित करता है ?

Read this question in English

"If rainforests and tropical forests are the lungs of the Earth, then surely wetlands function as its kidneys." Which one of the following functions of wetlands best reflects the above statement?

(a) The water cycle in wetlands involves surface runoff, subsoil percolation and evaporation. · (b) Algae form the nutrient base upon which fish, crustaceans, molluscs, birds, reptiles and mammals thrive. · (c) Wetlands play a vital role in maintaining sedimentation balance and soil stabilization. · (d) Aquatic plants absorb heavy metals and excess nutrients.

उत्तर और व्याख्या · explanation in English

Answer: (d) जलीय पादप भारी धातुओं और पोषकों के आधिक्य को अवशोषित कर लेते हैं ।

The kidney comparison is about purification: kidneys filter waste out of blood, and wetlands filter pollutants out of water. Option (d), aquatic plants absorbing heavy metals and excess nutrients, is the function that does this cleaning job.

  • ✓ (d) Wetlands are called the earth's kidneys because they filter pollutants. Wetland plants take up heavy metals, and plant roots and microbes absorb excess nutrients from fertilizer, manure and sewage.
  • ✗ (a) Runoff, percolation and evaporation describe how water moves through a wetland. This is the water cycle, not the removal of wastes.
  • ✗ (b) Algae as the base of the food chain is a habitat and food-web function, closer to a 'nursery' role than to a kidney's cleaning role.
  • ✗ (c) Sediment balance and soil stabilisation are physical, erosion-control functions. They do not purify water the way kidneys do.

Remember · Wetlands = kidneys of the landscape: they filter and purify water, with plants trapping heavy metals, pesticides and excess nutrients.

Sources

Question and answer: UPSC's official GS Paper I (2022, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). ·

Cite this question: UPSC CSE Prelims 2022, Q43 — minimalistias.com/pyqs/prelims/2022/q43

In the UPSC syllabus: Ecology & ecosystems › Wetlands, mangroves & special ecosystems See it and tick it covered →

Timed · 30 minutes Take Environment & ecology · Set 4 as a test This question is in it — with UPSC's marking and an instant score. Start the set Or the whole 2022 paper →

More on Ecology & ecosystems

All Ecology & ecosystems questions →

Same topic in the Mains syllabus