Trophic levels are formed by -

Question

UnlockIAS · Accepted Answer

Correct — C, Organisms linked in food chain. A trophic level is a feeding step in a food chain; it is defined by an organism’s position in the flow of food and energy. All organisms sharing the same feeding position — producers, herbivores, carnivores, decomposers — occupy the same trophic level. Since trophic levels arise from organisms linked together in a food chain, option (c) is correct.

Why the other options are wrong — (a) Plants (producers) form just the first trophic level. Trophic levels also include herbivores, carnivores and decomposers, so ‘plants only’ is incomplete.  (b) Carnivores occupy only the higher trophic levels (secondary/tertiary consumers). They alone cannot form all trophic levels, which begin with producers.  (d) This excludes producers (green plants/phytoplankton) and decomposers, which are essential trophic levels — the first level is made of producers, not animals.

Concept: In an ecosystem, energy flows from the Sun through producers to a series of consumers. Each feeding step is a trophic level: producers (1st), primary consumers/herbivores (2nd), secondary consumers (3rd), tertiary consumers (4th), with decomposers acting on all levels. Organisms linked in this feeding sequence — the food chain (and interlinked food webs) — constitute the trophic levels.

State PCS 2023 Q118 — Environment & Ecology PYQ with Answer

State PCS 2023 Q118 — Environment & Ecology PYQ with Answer