Which one of the following is the best description of the term 'ecosystem'?
Answer & explanation
Answer: (c) A community of organisms together with the environment in which they live
An ecosystem has two parts: the living organisms of an area (biotic) and the non-living physical surroundings (abiotic). It is the whole system formed when these interact. Only option (c) includes both the community and its environment.
- ✗ (a) This describes only a biotic community. It leaves out the non-living environment (soil, water, air, temperature, light), which is an essential part of an ecosystem.
- ✗ (b) This is the idea of the biosphere, the whole zone of the Earth where life exists. An ecosystem is a functional unit in a particular area, not the entire inhabited part of the planet.
- ✓ (c) This matches the standard definition. Living organisms together with the non-living constituents of their surroundings, interacting with each other, form an ecosystem.
- ✗ (d) Flora and fauna are only the plants and animals of a region. The term leaves out the non-living physical environment and the interactions between living and non-living components.
Remember · Ecosystem = biotic community + abiotic environment, interacting as one unit. Community alone is not an ecosystem, and the biosphere is the sum of all ecosystems.
📘 Read it in NCERT: Class 10 Science, Ch 13 (practise this chapter)
Sources
- NCERT Class 10 · Science, Chapter 13 “All the interacting organisms in an area together with the non-living constituents of the environment form an ecosystem.”
Question: UPSC Civil Services (Preliminary) 2015, General Studies Paper I. Explanation: Minimalist IAS, checked 25 Oct 2026 (how we verify). ·
