How Nature Works in Harmony
About this chapter
How Nature Works in Harmony is the twelfth chapter of Class 8 Curiosity. Opening with elephants entering farms in Odisha, Jharkhand, West Bengal, Assam and Chhattisgarh, it builds the core ecological ideas. A habitat has biotic components (plants, animals, microorganisms) and abiotic components (air, water, soil, sunlight, temperature). A group of the same kind of organism in one habitat is a population; different populations sharing a habitat form a community. Biotic and abiotic components interacting form an ecosystem — aquatic (pond, river, lake), terrestrial (forest, grassland, desert) or human-made (farm, fish pond). Organisms are producers (autotrophs), consumers (heterotrophs — herbivores, carnivores, omnivores) and decomposers (saprotrophs — fungi, bacteria) that recycle nutrients. Food chains show who eats whom; food webs interlink chains; trophic levels are positions in a chain. Relationships also include mutualism, commensalism and parasitism. The chapter ends with threats — Sundarbans loss, Green Revolution overuse, monoculture, pesticides — and the Indian bullfrog case. CTET tests definitions, classification, food chain reasoning, conservation. Four tests — Practice 15, Quiz 15, Hard 15, Mastery 30 — cover these.
Tests in this chapter
Build the basics. Single-concept recall and direct application.
Start test → Quiz 15 questions 15 minTest your understanding. Mixed application across the chapter.
Start test → Hard 15 questions 18 minPYQ-grade. Statement-based, assertion–reasoning, two-step problems.
Start test → Mastery 30 questions 30 minFull-chapter mock. Mixed difficulty, no overlap with the other three.
Start test →