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← Our Environment — all chaptersEnvironment
Start here: why this chapter matters
In simple wordsLook up from this page. Everything you can see, hear, breathe and touch — the air, the table, the tree outside, the traffic, the people in the room — is your environment. This chapter gives names to its parts and asks one question that runs through all of geography: how do people and nature shape each other?
This is Chapter 1 of NCERT's Class 7 geography book Our Environment (reprint 2024–25), book pp. 1–6 (6 PDF pages; QR code 0762CH01). It is told through a class of students — Ravi, Paramjeet, Jessy, Mustafa, Asha, Iqbal, Heera and Nurie — and covers what the environment is, its components (Fig. 1.1), biotic and abiotic parts, the four domains (Fig. 1.2), the ecosystem (Fig. 1.3, a pond) and the human environment. It is short — about four pages of text — so we use five concept sections, not padded ones. There are no maps and we draw none; the book's paintings are described in words and redrawn as our own schematics. Anything beyond the book is marked †.
- How this chapter relates to UPSC: it gives the vocabulary of GS3's environment and ecology paper and GS1's physical geography — environment, ecosystem, biosphere, biotic and abiotic. Prelims has asked the best definition of an ecosystem (2015) and the date of World Environment Day (2001). Everything harder (food chains, productivity, biosphere reserves) is taught in the senior chapters below.
- The senior versions: kegy214 (Biodiversity and Conservation); kegy207 (Composition and Structure of Atmosphere); kegy203 (Interior of the Earth — what the lithosphere really is); kegy212 (Water — Oceans); kegy105 (Natural Vegetation — biosphere reserves); legy101 (Human Geography — determinism and possibilism); kesy203 (Class 11 sociology, Environment and Society); Class 9 iest202 (Life on Earth).
- Next door: hess401 (Class 8, Resources) and hess402 (Land, Soil, Water, Natural Vegetation and Wildlife) take these domains further as resources; the rest of this book (gess202 onwards) goes inside the earth, its landforms, air and water.
- UPSC from this chapter: 2 Prelims questions (2001, 2015); no Mains question rests on it alone. List at the end.
| Word | What it means here |
|---|---|
| Environment | The place, people, things and nature that surround any living organism |
| Natural environment | Land, water, air, plants and animals — biotic and abiotic conditions on the earth |
| Human made environment | What people build: parks, buildings, bridges, roads, industries, monuments |
| Human environment | The activities, creations and interactions among human beings |
| Biotic / abiotic | The world of living organisms (plants, animals) / of non-living elements (e.g. land) |
| Lithosphere | The solid crust or hard top layer of the earth: rocks, minerals, a thin layer of soil |
| Hydrosphere | The domain of water: rivers, lakes, seas, oceans |
| Atmosphere | The thin layer of air around the earth, held by gravity |
| Biosphere | The living world: a narrow zone where land, water and air interact to support life |
| Ecosystem | Living organisms interacting with each other and their physical and chemical surroundings, linked by transfer of energy and material (glossary) |
| Barter system | Trade in which goods are exchanged without money (glossary) |
Reading the chapter opener, the forest photograph, the sidebar and the class cartoon (page 1)
- Opener: a pink-and-purple banner with a yellow cartoon sun, the number 1 and the handwritten-style title ‘Environment’; a QR code (0762CH01).
- Photograph (colour) in a blue sidebar: a dense wall of green forest — trees, ferns and climbers. Sidebar text: the environment is our basic life support system, giving the air, water, food and land; people modify it — car fumes pollute air, water is collected in a pot, food is served in vessels, land is used for factories; people make cars, mills, factories and containers. The point: nature supports us and we change it (our diagram sorts these).
- Cartoon: five smiling children — a boy in a striped shirt, a boy in a yellow patka, a girl in a red dress with bows, a boy in a cap with arms folded, a girl in pink — ready to make the list. The point: the pair-work activity (in-text answer below).
At a glance — the six ideas to carry away
- Environment: the places, people, things and nature around a living organism — natural + human made; our basic life support system (air, water, food, land).
- Fig. 1.1: natural (land, water, air, living things) · human made (parks, buildings, bridges, roads, industries, monuments) · human (individual, family, community, religion, education, economy, politics).
- Biotic = living (plants, animals); abiotic = non-living (e.g. land).
- Four domains: lithosphere (solid crust, rocks, minerals, soil) · hydrosphere (water bodies) · atmosphere (air held by gravity; weather) · biosphere (narrow zone where land, water, air meet).
- Ecosystem: living organisms interacting with each other and with their physical surroundings, linked by energy and material — a rain forest or a pond; an aquarium is human made.
- Human environment: from adapting to nature → farming → wheel → barter → trade → industry → information revolution. Need a balance. World Environment Day: 5 June.
1. What is the environment?
In simple wordsA fish's environment is the water, the weeds, the other fish and the glass of its bowl. Yours is the air, the roads, your home, your family and your friends. ‘Environment’ is simply whatever surrounds a living thing — and it includes both what nature made and what people made.
After the vacation, Ravi finds the only playground next to his school dug up for a large building of flats; the soft grass, marigolds and butterflies are gone for ever. The Principal sadly says the environment is changing. Asked ‘What is environment?’, the teacher says: whatever you see in your surroundings. Ravi lists the school building, tables, chairs, the open field, the road, the garbage, his friends. The teacher adds that some things are created by nature (mountains, rivers, trees, animals) and others made by people (roads, cars, clothes, books). Why is it changing? Because our needs are increasing, so we modify and at times even destroy our natural surroundings. The book's definition: the place, people, things and nature that surround any living organism is the environment, a combination of natural and human made phenomena. It is our basic life support system, giving the air we breathe, the water we drink, the food we eat and the land where we live.
⤵ Why Ravi's environment changed (pp. 1–2)
Needs growmore people need homes, roads, goods
Land is usedthe playground is dug up for a building of flats
Nature lostgrass, marigolds and butterflies gone for ever
Modifypeople change the environment to meet needs
At times destroysome changes cannot be undone
Lessonseek a balance between natural and human environment (p. 5)
| Who should decide what happens to an open field like Ravi's? — positions side by side († rows; no position endorsed) | Who | Position |
|---|---|---|
| Balance and harmony | NCERT (pp. 2, 5) | needs drive change, which can destroy surroundings; a perfect balance between natural and human environment is necessary |
| Homes are needed † | families needing housing; builders and urban planners | growing towns need flats, roads and services; land must be put to use |
| Open spaces are needed † | residents, children, advocates of urban green space | parks and playgrounds give play, health, shade and habitat that cannot be replaced once built over |
| Plan both † | town-planning approaches (kesy202, legy202) | zoning can reserve open space while allowing housing elsewhere |
Reading the ‘Word Origin’ box (page 3)
- A cartoon character with a book: ‘Environment’ comes from the French Environer/Environner, glossed as ‘neighbourhood’. The point: environment = surroundings. (See the trap: the French verb means ‘to surround’.)
NCERT details to read carefully — what is environment
- The book's definition covers place, people, things and nature — people are part of the environment, not outside it.
- Word origin: Old French environner means ‘to surround’ (environ, ‘around’) †; ‘neighbourhood’ is a loose gloss. Safe line: ‘from the French for surroundings’.
- The sidebar's ‘the air we breath’ should read ‘breathe’.
- Exercise 3(iv): environment → (d) our surroundings.
2. Components: natural, human made and human
In simple wordsThink of your school as three layers: the ground, trees, air and rain it sits in (natural); the buildings, gates and road outside (human made); and the students, teachers, rules and festivals that fill it (human). Take any one away and it is no longer the same school.
Fig. 1.1 is a web with ‘Components of Environment’ at the centre and three branches. Natural: land (lithosphere), water (hydrosphere), air (atmosphere) and living things (biosphere). Human made: parks, buildings, bridges, roads, industries and monuments. Human: individual, family, community, religion, educational, economic and political situation. The natural environment covers both biotic conditions — the world of living organisms, such as plants and animals — and abiotic conditions — the world of non-living elements, such as land. The human environment reveals the activities, creations and interactions among human beings.
| Biotic and abiotic (the book's box, p. 2) — with a pond as example | Biotic (living) | Abiotic (non-living) |
|---|---|---|
| Book's examples | plants and animals | land |
| In a pond | water plants, fish, frogs, insects, ducks; bacteria † | water, mud, sunlight, air, temperature |
| Which domain | biosphere | lithosphere, hydrosphere, atmosphere |
Reading Fig. 1.1 and the biotic–abiotic box (page 2)
- Fig. 1.1, ‘Components of Environment’: a large yellow-orange circle at the centre joined to three smaller circles — green ‘Natural’, purple ‘Human made’, blue ‘Human’ — each with arrows to small coloured paintings: clouds in the sky, a palm-tree island, hills with a village, a waterfall with trees and animals (natural); a block of flats, a garden with swings, a suspension bridge, a winding road, factory chimneys with smoke, a domed monument and a tower (human made); a man, a family, people under a tree, shrines of several faiths, children at desks, a market street, and figures standing on an outline of India for ‘political situation’ (human). The point: the environment has three strands, not two.
- Box: ‘Biotic — the world of living organisms, e.g. plants and animals’ and ‘Abiotic — the world of non-living elements, e.g. land’, joined by a drawing of two clasped hands. The point: living and non-living depend on each other.
NCERT details to read carefully — components
- Three branches in Fig. 1.1 (natural, human made, human) but two in the text (‘natural and human made’). Answer a ‘major components’ question with all three.
- Exercise 2(ii): land is natural — not a component of the human environment; religion and community are.
- Exercise 2(iii): the road is human made; mountain and sea are natural.
- Exercise 1(vi): the book's two major biotic components are plants and animals; micro-organisms (bacteria, fungi) are living too †.
3. The four domains of the natural environment
In simple wordsPicture a fish tank: gravel at the bottom (land), water above it, air at the top, and the fish and weeds living where all three meet. The earth is the same, on a giant scale — rock, water and air, with a thin skin of life where they touch.
Land, water, air, plants and animals make up the natural environment, in four domains. The lithosphere is the solid crust or hard top layer of the earth, made of rocks and minerals covered by a thin layer of soil; it is irregular, with mountains, plateaus, plains and valleys, on the continents and on the ocean floors. It gives us forests, grasslands for grazing, land for farming and settlements, and mineral wealth. The hydrosphere is the domain of water — rivers, lakes, seas, oceans — essential for all living organisms. The atmosphere is the thin layer of air around the earth, held by the earth's gravitational force; it protects us from the sun's harmful rays and scorching heat, consists of gases, dust and water vapour, and its changes produce weather and climate. The biosphere — the plant and animal kingdom, the living world — is a narrow zone where land, water and air interact to support life.
| The four domains at a glance | Made of | Gives us / does | Senior chapter |
|---|---|---|---|
| Lithosphere | rocks, minerals, thin soil; landforms | forests, grazing, farms, settlements, minerals | kegy203, kegy205, iest102 |
| Hydrosphere | rivers, lakes, seas, oceans | water for all life | kegy212, kegy213 |
| Atmosphere | gases, dust, water vapour | shields from harmful rays and heat; weather and climate | kegy207, iest103 |
| Biosphere | plants and animals (and micro-organisms †) | life, where the other three meet | kegy214, iest202 |
Reading Fig. 1.2 and the three ‘Let's do’ boxes (page 3)
- Fig. 1.2, ‘Domains of the Environment’: a round painting — sky with an aeroplane (‘Atmosphere’), snow-capped mountains, a sea with a sailboat and palms (‘Hydrosphere’), a road with a red bus, houses and a farmer on a tractor in green fields (‘Lithosphere’), and a dashed circle overlapping all three around elephants, ducks and cattle (‘Biosphere’). The point: life sits where land, water and air overlap (our circles make the same point).
- Let's do (three boxes): list the uses of land in your neighbourhood; where does your home's and school's water come from, list its uses, have you seen anyone wasting it; observe the sky on the way to school — cloudy, rainy, sunny, foggy? The point: each domain in your own day (outlines in the in-text section).
Beyond NCERT — the domains, precisely (bare facts)
- Lithosphere in geology = the crust plus the uppermost solid mantle (kegy203) — more than ‘the crust’.
- Dry air is about 78% nitrogen, 21% oxygen and 0.9% argon by volume (kegy207); the ozone layer in the stratosphere absorbs much of the sun's harmful ultraviolet rays — the ‘harmful rays’ of the book.
- Water covers about 71% of the earth's surface (hess402).
NCERT details to read carefully — domains
- The atmosphere is held by gravity — but in exercise 3, ‘(c) gravitational force of the earth’ is a leftover: atmosphere → (a) blanket of air.
- Biosphere → (e) narrow zone where land, water and air interact; hydrosphere → (b) domain of water.
- ‘Plant and animal kingdom together make biosphere’ leaves out micro-organisms †; the biosphere is both the living things and the zone they live in.
- Landforms exist on the ocean floor too, not just on continents.
4. Ecosystems: everything connected
In simple wordsIn a pond, the lilies need sunlight and mud, the fish need the lilies' oxygen and shelter, the ducks eat the fish, and when anything dies the mud takes it back. Pull one thread and the others move. That web of living things and their surroundings is an ecosystem — and a pond, a desert or a whole rain forest can be one.
At an NCC camp, Jessy says the heavy rain reminds her of Kerala, where it pours over lush green fields and coconut plantations. Heera from Jaisalmer says they get no rains — only kikar and sand; Ravi adds camels; Heera adds snakes, lizards and many insects. Ravi wonders why animals, vegetation and ways of life vary from place to place and whether they are related — ‘very much so’, says the teacher. All plants, animals and human beings depend on their immediate surroundings and are often interdependent. This relation between living organisms, and between organisms and their surroundings, forms an ecosystem. There can be an ecosystem of a large rain forest, grassland, desert, mountains, lake, river, ocean and even a small pond. The glossary's fuller definition: a system formed by the interaction of all living organisms with each other and with the physical and chemical factors of their environment, all linked by transfer of energy and material.
⤵ How an ecosystem works (glossary, p. 4; decomposers †)
Energy insunlight reaches plants
Plantsuse sunlight, water, air and soil to grow
Animalseat plants, or other animals
Death and decaybacteria and fungi break down dead matter (Beyond NCERT)
Material recyclednutrients return to soil and water for plants again
Reading the ecosystem glossary, the ‘Let's do’ and Fig. 1.3 (page 4)
- Glossary: ecosystem (as above).
- Let's do: sketch or bring photographs of your place, like the students in the story.
- Fig. 1.3, ‘A Pond Ecosystem’ (watercolour): a waterfall tumbling off brown rocks into a blue pool with pink water lilies, two grey swans or geese, tall grass and trees with a small bird, spotted deer and grey cattle drinking at the bank. The point: plants, animals, water, rock and air in one connected scene (our schematic labels the parts).
Beyond NCERT — the word and the idea
- The term ecosystem was coined by the British ecologist Arthur Tansley in 1935.
- UPSC 2015 asked the best description: ‘a community of organisms together with the environment in which they live’ — not organisms alone, not just flora and fauna, not the inhabited part of the earth (that is the biosphere).
- Producers, consumers, decomposers, food chains and productivity are taught in kegy214 and iest202.
NCERT details to read carefully — ecosystems
- An ecosystem includes the non-living surroundings too — interaction with ‘physical and chemical factors’, not only living things.
- Size does not matter: a small pond is as much an ecosystem as a rain forest.
- Exercise 2(i): an aquarium is not a natural ecosystem — it is human made (an artificial ecosystem †); desert and forest are natural.
- Exercise 3: ‘(f) relation between the organisms and their surroundings’ describes an ecosystem — a leftover in the match.
- ‘In-text: was Ravi's park an ecosystem?’ — yes: grass, flowers, butterflies, soil, air and water interacting.
5. The human environment: adapting, then remaking
In simple wordsA family that moves into a hut by a river first lives as the river allows — fishing, drinking, avoiding floods. A few generations later they have built a dam, a road, a market and a phone tower. Same river, same land — but now people are shaping nature more than nature shapes them.
Human beings interact with the environment and modify it according to their needs. Early humans adapted to their natural surroundings, leading a simple life and meeting their needs from the nature around them. Needs grew and became more varied; humans learnt to grow crops, domesticate animals and lead a settled life. The wheel was invented, surplus food was produced, the barter system emerged, trade started and commerce developed. The Industrial Revolution enabled large-scale production; transport became faster; the information revolution made communication easy and speedy across the world. Why do we love a juicy watermelon in summer and hot roasted peanuts in winter? Our lives still follow nature's seasons. A perfect balance between the natural and human environment is necessary; humans must learn to live and use their environment harmoniously. The chapter ends with Nurie from Mizoram inviting Ravi to her lush green home state, and the teacher asking the class to draw the landscapes, houses and activities of places they visit in the holidays. A ‘Do you know?’: World Environment Day is celebrated on 5 June every year.
⤵ From adapting to modifying (p. 5)
Adaptearly humans: simple life, needs met from nature
Settlecrops, domesticated animals, settled life
Exchangethe wheel, surplus food, barter, trade, commerce
TransformIndustrial Revolution, faster transport, information revolution
Balancelive with and use the environment in a harmonious way
| How far does nature shape people? — positions side by side († rows; no position endorsed) | Who | Position |
|---|---|---|
| Balance and harmony | NCERT (p. 5) | early people adapted; later people modified; a perfect balance is needed |
| Environmental determinism † | associated with Friedrich Ratzel and Ellen Churchill Semple (legy101) | the natural environment largely decides how people live |
| Possibilism † | associated with Paul Vidal de la Blache (legy101) | nature offers possibilities; people choose among them, more so with technology |
| Neo-determinism (‘stop and go’) † | Griffith Taylor (legy101) | people can change the environment, but within limits nature sets |
| Society shapes environment too † | environmental sociology (kesy203) | how environments are used depends on social organisation, class and power |
Reading the World Environment Day box, the barter glossary and photograph, and the elderly-person ‘Let's do’ (page 5)
- Do you know?: on 5 June every year World Environment Day is celebrated.
- Glossary — Barter system: trade in which goods are exchanged without money; a photograph shows three people kneeling around a blue sheet on dry ground, exchanging small heaps of goods. The point: trade before money.
- Let's do: talk to an elderly person about the trees in their neighbourhood when they were your age, the indoor games they played, their favourite fruit, and how they kept comfortable in hot summers and cold winters; display the answers. The point: the human environment changes within one lifetime (outline below).
Beyond NCERT — World Environment Day (bare facts)
- The UN Conference on the Human Environment met in Stockholm from 5 June 1972; the UN General Assembly then designated 5 June as World Environment Day, first observed in 1973. The UN Environment Programme (UNEP) was also set up in 1972 (kesy203 has the Stockholm–Rio timeline).
- UPSC 2001 matched World Environment Day with 5 June and World Ozone Day with 16 September.
NCERT details to read carefully — human environment
- The book's order: adapt → crops and animals, settled life → wheel → surplus food → barter → trade, commerce → Industrial Revolution → faster transport → information revolution. It gives no dates; do not invent any.
- Exercise 4(i), why people modify the environment: growing and varied needs — food, shelter, transport, industry.
- Exercise 2(iv): the book's answer to ‘a threat to environment’ is (b) growing population — growing plants and crops are part of nature. Note that how people consume and produce matters as much as their number (hess405 sets out the asset–burden debate).
- World Environment Day = 5 June; do not confuse with World Ozone Day (16 September) or Earth Day (22 April) †.
In-text questions and activities — answer outlines
Every question and ‘Let's do’ in the text, in page order.
(p. 1) Work in pairs: make a list of the creations of nature and of human beings.
Nature: mountains, rivers, trees, animals, soil, rain, sunlight, air, grass, flowers, butterflies. People: roads, cars, clothes, books, buildings, tables, chairs, bridges, factories, containers. Tricky ones: a park is human made though its plants are natural; garbage is human made.
(p. 3) Let's do: Look at your surroundings and list the uses the land in your neighbourhood is put to.
Houses, shops, markets, schools, roads, parks and playgrounds, temples or other places of worship, hospitals, fields or gardens, factories or workshops, bus stops, waste dumps. Note which are natural (fields, groves) and which built.
(p. 3) Let's do: Where does the water used in your home and school come from? List its uses. Have you seen anyone wasting water? How?
Sources: municipal tap, borewell or handpump, well, tanker, river or pond, rainwater tank. Uses: drinking, cooking, bathing, washing clothes and utensils, flushing, cleaning, gardening. Waste: taps left running, leaking pipes, overflowing tanks, washing vehicles with a hose.
(p. 3) Let's do: Observe the sky while coming to school — is the day cloudy, rainy, sunny, foggy?
Keep a one-week chart: date, sky (sunny, cloudy, rainy, foggy, hazy), how it felt (hot, cold, humid). The changes you record are the atmosphere's weather; the pattern over many years is climate.
(p. 4) Let's do: Sketch or bring photographs of your place, like the students in the story.
Show the land (flat, hilly, coastal), water (river, pond, sea), common plants and animals, the houses, and what people do (farming, shops, offices). Add one line on how the place's climate shapes life — like Kerala's rain or Jaisalmer's sand.
(p. 5) Do you think the park in which Ravi and his friends played formed an ecosystem?
Yes. Its living parts (grass, marigolds, butterflies, insects, birds, soil organisms) interacted with each other and with non-living parts (soil, water, air, sunlight). Butterflies pollinated flowers; plants fed insects. Destroying it broke that system.
(p. 5) Why do you love eating a juicy watermelon in summer and hot roasted peanuts in winter?
Our bodies and food habits follow the seasons: watery, cooling watermelon suits hot summers (and is harvested then), while oily, warm roasted peanuts suit cold winters (and are harvested after the monsoon †). The natural environment shapes how we live.
(p. 5) Let's do: Ask an elderly person about the trees in their neighbourhood at your age, their indoor games, their favourite fruit, and how they kept comfortable in hot summers and cold winters.
Record answers in a table: then vs now. Typical findings: more trees and open land then; games like ludo, carrom, pachisi, gilli-danda; seasonal local fruit; summers — thick walls, courtyards, clay pots, hand fans, sleeping on roofs; winters — quilts, fires, sun-bathing. Conclude how the human environment has changed (fans, coolers, ACs, screens).
(p. 5) The teacher's holiday task: draw the landscape, houses and activities of the people and places you visit.
Draw the land, water and vegetation; the type of houses (materials, roofs suited to rain or heat); the main work and food. Compare with your home: e.g. sloping roofs in rainy Mizoram vs flat roofs in dry Jaisalmer †.
Exercises (page 6) — answer outlines
Five exercises: short answers, multiple choice, matching, reasons and a drawing activity. Try first, then open.
1(i). What is an ecosystem?
A system formed by the interaction of living organisms with each other and with their physical surroundings, linked by transfer of energy and material — e.g. a pond, a forest, a desert.
1(ii). What do you mean by natural environment?
The environment made by nature — land, water, air, plants and animals — with both biotic (living) and abiotic (non-living) conditions; its four domains are the lithosphere, hydrosphere, atmosphere and biosphere.
1(iii). Which are the major components of the environment?
Natural (land, water, air, living things), human made (parks, buildings, bridges, roads, industries, monuments) and human (individual, family, community, religion, education, economy, politics) — Fig. 1.1.
1(iv). Give four examples of human made environment.
Any four: buildings, parks, bridges, roads, industries, monuments.
1(v). What is lithosphere?
The solid crust or hard top layer of the earth, made of rocks and minerals and covered by a thin layer of soil, with landforms such as mountains, plateaus, plains and valleys on land and on the ocean floor. It gives forests, grazing land, farmland, space for settlements and minerals.
1(vi). Which are the two major components of biotic environment?
Plants and animals (micro-organisms are also living †).
1(vii). What is biosphere?
The living world — the plant and animal kingdom — in the narrow zone of the earth where land, water and air interact to support life.
2(i). Which is not a natural ecosystem? (a) Desert (b) Aquarium (c) Forest
(b) Aquarium — made and maintained by people.
2(ii). Which is not a component of human environment? (a) Land (b) Religion (c) Community
(a) Land — a natural component.
2(iii). Which is a human made environment? (a) Mountain (b) Sea (c) Road
(c) Road.
2(iv). Which is a threat to environment? (a) Growing plant (b) Growing population (c) Growing crops
(b) Growing population (the book's answer: more people mean more needs and more modification).
3. Match: (i) Biosphere (ii) Atmosphere (iii) Hydrosphere (iv) Environment — with (a) blanket of air which surrounds the earth (b) domain of water (c) gravitational force of the earth (d) our surroundings (e) narrow zone where land, water and air interact (f) relation between the organisms and their surroundings
(i) → (e); (ii) → (a); (iii) → (b); (iv) → (d). (c) and (f) are left over — (f) describes an ecosystem.
4(i). Give reasons: Man modifies his environment.
Because human needs grow and become varied — food, shelter, clothing, transport, goods. To meet them people farm, build houses and roads, set up industries and use resources, changing the natural environment (from early adaptation to the industrial and information revolutions).
4(ii). Give reasons: Plants and animals depend on each other.
Plants give animals food, oxygen and shelter; animals help plants by pollination (bees, butterflies), spreading seeds, and returning nutrients through dung and decay; animals breathe out carbon dioxide that plants use †. Together with their surroundings they form an ecosystem.
5. Activity: Imagine an ideal environment where you would love to live. Draw the picture of your ideal environment.
Include clean air and water, trees and open spaces (a playground like Ravi's), homes, schools and hospitals within reach, clean energy (solar panels), public transport and cycle paths, waste bins and recycling — a balance of natural and human made, as the chapter urges.
Reading the exercise page (page 6)
- A cartoon globe with arms and legs under an ‘Exercises’ banner, and a smiling cloud at the foot of the page; the five exercises above.
Keys and slips to handle with care
- Exercise keys: 2(i) (b); 2(ii) (a); 2(iii) (c); 2(iv) (b); 3: e, a, b, d.
- Book slips with safe lines: ‘environner’ = to surround (not ‘neighbourhood’); two components in the text vs three in Fig. 1.1; biosphere = plants and animals (micro-organisms omitted); lithosphere = crust (geology: crust + uppermost mantle); ‘breath’ for breathe; ‘Man modifies his environment’ — read as ‘people’.
- Stored UPSC keys: 2015 (ecosystem) key (c) is correct. 2001 (important days) key (d) is right by elimination — June 5 and September 16 are certain — but its other pairings are dated: World Forestry Day is usually 21 March (since 2013 the UN's International Day of Forests) †, so the option's ‘March 20’ is disputed; World Habitat Day is the first Monday of October, not a fixed date. Kept, with this note. None of the pending key issues applies.
⤵ Answer frame for a basic environment or ecology question
Defineenvironment, ecosystem or biosphere in one precise line
Partsbiotic and abiotic; the four domains; natural, human made, human
Linksenergy flows from the sun; materials cycle; interdependence
Human roleadapt, then modify; needs and technology
Viewsdeterminism, possibilism, neo-determinism — attributed side by side
Concludebalance and harmony, with no comment on any present-day party or government
What to remember
Numbers
ChapterClass 7, Our Environment, Ch. 1, book pp. 1–6 (6 PDF pages); QR 0762CH01; reprint 2024-25
Definitionplace, people, things and nature surrounding any living organism; natural + human made
Life support (sidebar)air we breathe, water we drink, food we eat, land where we live
Fig. 1.1 — natural (4)Land (lithosphere), Water (hydrosphere), Air (atmosphere), Living things (biosphere)
Fig. 1.1 — human made (6)Parks, Buildings, Bridges, Roads, Industries, Monuments
Fig. 1.1 — human (7)Individual, Family, Community, Religion, Educational, Economic, Political situation
Biotic / abioticliving (plants, animals) / non-living (e.g. land)
Four domainslithosphere, hydrosphere, atmosphere, biosphere
Atmosphere (book)thin layer of air held by gravity; gases, dust, water vapour; shields from harmful rays; weather and climate
Air †nitrogen 78.08%, oxygen 20.95%, argon 0.93% of dry air (kegy207)
Ecosystems named (8)large rain forest, grassland, desert, mountains, lake, river, ocean, small pond
Ecosystem †term coined by Arthur Tansley, 1935
Ladder of change (9)adapted to nature → grew crops, tamed animals, settled → the wheel → surplus food → barter → trade and commerce → Industrial Revolution → faster transport → information revolution
World Environment Day5 June (book); Stockholm conference 1972, first observed 1973 †
Places in the storyKerala (rain, coconut), Jaisalmer (no rain, kikar, sand, camels), Mizoram (lush green)
Word originFrench environner — ‘to surround’ † (book: ‘neighbourhood’)
One-liners
- The environment is everything around a living thing — natural and human made.
- It is our basic life support system: air, water, food and land.
- Fig. 1.1: natural, human made and human components.
- Biotic means living; abiotic means non-living.
- Lithosphere is land, hydrosphere water, atmosphere air; the biosphere is where they meet.
- The atmosphere is held by gravity and shields us from harmful rays.
- An ecosystem is living things interacting with each other and their surroundings.
- A pond can be an ecosystem as much as a rain forest.
- People first adapted to nature, then modified it as needs grew.
- World Environment Day is 5 June.
Traps to avoid
- Fig. 1.1 has three branches; the text names only two kinds of environment.
- Land is natural — not a component of the human environment.
- An aquarium is not a natural ecosystem.
- An ecosystem includes the non-living surroundings, not just organisms.
- In the match, ‘gravitational force’ and ‘relation between organisms and surroundings’ are leftovers.
- The biosphere includes micro-organisms, not only plants and animals.
- Geologists define the lithosphere as crust plus uppermost mantle.
- ‘Environner’ means to surround; ‘neighbourhood’ is the book's loose gloss.
- World Environment Day is 5 June; World Ozone Day 16 September.
- The book's ladder of human change has no dates.
How to strategise
Prelims — what UPSC asks
- From this chapter: the best description of an ecosystem — organisms together with their environment (2015); World Environment Day on 5 June in a match of important days (2001, other pairings dated).
- Elsewhere: decomposers and food chains (2013), ecosystem productivity (2013), ozone (1982, 1986, 1987), biosphere reserves (1995–2019) are taught in kegy214, kegy207 and kegy105 — learn them there.
Mains — where it appears and how to answer
- No Mains question rests on this chapter alone; it supplies the definitions (environment, ecosystem, biosphere, biotic and abiotic) that open answers on ecosystems (e.g. GS3 2019 on carrying capacity, legy206) and on human–environment relations (legy101, kesy203).
- Keep answers neutral: define precisely, give dated facts with sources, set views on nature and society side by side, and avoid present-day political commentary.
Self-check
Tap an option. NCERT's own exercise questions come first; the rest test the figures and common confusions.
1. According to the book, the environment is:
2. Which of these is a human made component in Fig. 1.1?
3. The ‘abiotic’ environment means:
4. Which domain is held around the earth by its gravitational force?
5. The biosphere is best described as:
6. Which one is NOT a natural ecosystem?
7. The best description of an ecosystem is:
8. World Environment Day is celebrated on:
UPSC questions from this chapter
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