Secondary Producers in Ecosystem — NEET Biology

Correct answer: B — a–II–Q, b–I–R, c–III–S, d–IV–P

Let's establish the correct matches for each trophic level: - **a. Producers:** These are organisms that produce their own food. In an aquatic ecosystem, these are phytoplankton. Their ecological role is to fix radiant energy from the sun using simple inorganic materials. So, a matches with II and Q. - **b. Primary Consumers:** These are herbivores that feed on producers. In an aquatic ecosystem, zooplankton feed on phytoplankton. Their ecological role is to feed on producers. So, b matches with I and R. - **c. Secondary Consumers:** These are primary carnivores that feed on primary consumers (herbivores). Small fish often feed on zooplankton. Their ecological role is to consume herbivores. So, c matches with III and S. - **d. Tertiary Consumers:** These are secondary carnivores that feed on secondary consumers (primary carnivores). Large predatory fish typically feed on smaller fish. Their ecological role is to consume primary carnivores. So, d matches with IV and P. Combining these, the correct set of matches is a–II–Q, b–I–R, c–III–S, d–IV–P. This question tests the understanding of trophic levels and the specific examples and roles of organisms within an aquatic food chain, as described in the NCERT text.