CBSE 2025 · Region 5 · Set 1 · Q21 · 2 marks
Explain how the interaction between a fig tree and its tight one-to-one relationship with the pollinator species of wasp is one of the best examples of mutualism.Correctly depict (also indicate the trophic level) and describe the ecological pyramid of number with $\displaystyle 32$ birds dependent on $\displaystyle 20$ insects feeding on one banyan tree.
Explain how the interaction between a fig tree and its tight one-to-one relationship with the pollinator species of wasp is one of the best examples of mutualism.
Correctly depict (also indicate the trophic level) and describe the ecological pyramid of number with $\displaystyle 32$ birds dependent on $\displaystyle 20$ insects feeding on one banyan tree.
Marking-scheme solution
Fig species can be pollinated only by its ‘partner’ wasp species and no other
species, the female wasp uses the fruit not only as an oviposition
(egg-laying) site, but also uses the developing seeds within the fruit for nourishing the larvae, the wasp pollinates the fig inflorescence while searching for suitable egg-laying site.
Ecological pyramid of number.
Trophic levels: Secondary Consumer/SC = $\displaystyle 32$ (Birds), Primary Consumer/PC = $\displaystyle 20$ (insects), Primary Producer/PP = $\displaystyle 1$ (Banyan tree).
EcosystemEcosystem – Structure and FunctionUnderstandvery_short_answermedium
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CBSE Class 12 Biology past-paper question from the 2025board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.