Population Size in Food Chains — NEET Biology
📚 Practice ConceptWhich one of the following has the largest population in a food chain? (a) Producers (b) Primary consumers (c) Secondary consumers (d) Decomposers
Which of the following statements regarding energy flow and decomposition in an ecosystem are NOT correct? S1: Solar energy, the ultimate source for most ecosystems, is captured by plants, which convert less than 50% of the incident solar radiation into Photosynthetically Active Radiation (PAR). S2: Only about 2-10% of the Photosynthetically Active Radiation (PAR) captured by producers is passed on to primary consumers. S3: Decomposers mineralize dead organic matter, making inorganic nutrients available for reuse by autotrophs, thereby ensuring nutrient recycling. S4: The entire energy trapped by producers, once it leaves the consumer trophic levels, is recycled back to the producers by decomposers. S5: In a terrestrial ecosystem, the detritus food chain typically accounts for a much larger fraction of energy flow compared to the grazing food chain.
View solution & NCERT explanation
Correct answer: C — S1 and S4 only
The core concept here is the unidirectional flow of energy and the role of decomposers in nutrient cycling, not energy recycling. S1 is NOT correct: The NCERT states that less than 50% of incident solar radiation is PAR. It is plants that capture only 2-10% of the PAR, not less than 50% of incident solar radiation for PAR. The statement incorrectly implies plants convert less than 50% incident solar radiation into PAR itself, which is not what NCERT states. It's less than 50% of total solar radiation is PAR, and then 2-10% of PAR is captured by plants. S2 is correct: Plants capture only 2-10% of the PAR (Page 209). This captured energy is then transferred following the 10% law. S3 is correct: Decomposers break down complex organic matter into inorganic substances and mineralize dead matter, releasing nutrients back for reuse by autotrophs (Page 207, 206). S4 is NOT correct: Energy flow is unidirectional and is lost as heat at each trophic level; it is not recycled back to producers (Page 206, 214). Nutrients are recycled, not energy. S5 is correct: In a terrestrial ecosystem, a much larger fraction of energy flows through the detritus food chain than through the grazing food chain (Page 210). Therefore, statements S1 and S4 are NOT correct. This question evaluates the understanding of energy flow, PAR, and the distinct roles of decomposers regarding energy versus nutrient dynamics.
What does NCERT say about Which one following has?
Has this concept appeared in NEET?
Which chapter is this from?
Through deep analysis of NEET and NTA, 176 of the 180 ReNEET 2026 (June 21) questions were already in the MedicNEET question bank before the exam.
176/180MedicNEET's Biology question bank is built from the same NCERT lines NTA picks repeatedly. Not random MCQs — questions crafted exactly like NTA crafts them.