Life on Earth — Class 9 MCQs with Answers
Class 9 CBSE Social Science · Chapter 11
78 practice questions · 25 Easy · 28 Medium · 25 Hard · Updated
Jump to the 6 solved questions
Practise the most important Class 9 CBSE Social Science questions from Chapter 11, "Life on Earth". You get 10 timed quizzes made from 78 NCERT-based MCQs, with answers and explanations. The questions are split into 25 Easy, 28 Medium and 25 Hard. Warm up on the basics, then move on to the exam-level questions that top scorers in CBSE Board exams get right.
To score well in "Life on Earth", focus on dates, cause and effect, and reading maps and sources. Each MCQ here is timed and uses exam-style marking (+4 correct, −1 wrong, 0 skipped). This helps you stay accurate when time is short, just as real papers need. Every question has a short explanation, so a wrong answer becomes a quick lesson. It is the fastest way to fix gaps before a test.
Use this chapter for focused revision. Start with the Easy set to check your basics on Life on Earth, then move to Medium and Hard to practise applying them. Your accuracy, streaks and XP save automatically. This chapter also adds to your overall Class 9 Social Science mastery score. Try the 6 sample questions below: tap an option to see the answer and a worked explanation. Sign in free to start practising.
Life on Earth — important questions & MCQs with answers (Class 9 Social Science)
6 solved questions from this chapter's difficulty levels, each with its answer and explanation. Tap an option to check yourself.
0 of 6 answered
- Q1 of 6Easy
The term 'biodiversity' refers to:
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Answer: The variety of all living organisms on Earth
Explanation: Biodiversity means the variety of all forms of life — plants, animals and microorganisms — found on Earth.
- Q2 of 6Easy
The natural plant cover of a region that has grown on its own is called:
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Answer: Natural vegetation
Explanation: Natural vegetation is the plant life that grows naturally in a region without human help, suited to its climate and soil.
- Q3 of 6Medium
Which is the MAIN difference between a national park and a wildlife sanctuary?
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Answer: A sanctuary allows some regulated human activity, while a national park has stricter protection
Explanation: Sanctuaries permit certain regulated human activities for wildlife protection, whereas national parks enforce stricter, more complete protection.
- Q4 of 6Medium
Assertion (A): Grasslands are large open areas covered mainly with grass and very few trees. Reason (R): Grasslands develop in regions that receive heavy rainfall all through the year.
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Answer: A is true but R is false
Explanation: A is true. R is false: grasslands develop where rainfall is moderate, which is not enough to support dense forests.
- Q5 of 6Hard
A wheat crop disease wipes out almost an entire harvest because all the plants were genetically identical. This situation best demonstrates that:
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Answer: Low genetic diversity makes a species more vulnerable to being wiped out
Explanation: When all individuals are genetically alike, a single disease can destroy them all; genetic diversity provides resistance and resilience.
- Q6 of 6Hard
Assertion (A): As we move up a biome pyramid, the available energy decreases. Reason (R): Producers such as plants and algae, at the base of the pyramid, capture solar energy through photosynthesis.
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Answer: Both A and R are true but R is not the correct explanation of A
Explanation: Both are true. Energy decreases because some is lost as heat at each trophic level during metabolic processes. R only tells us where energy enters the pyramid, so it does not explain A.
Life on Earth notes: key concepts (Class 9 Social Science)
Life on earth is remarkably varied, and that variety is itself a resource. This chapter covers biodiversity and the ecosystems that sustain it, the forests that shelter much of it, the livelihoods that depend on them, and the case for conservation.
- 1Sun: the original source of energy, captured by producers
- 2Grass: producer, makes its own food by photosynthesis
- 3Grasshopper: primary consumer, eats the grass
- 4Frog: secondary consumer, eats the grasshopper
- 5Snake: eats the frog
- 6Decomposers (bacteria, fungi) break down dead matter and return nutrients to the soil
| Forest | Where it grows | How the plants cope |
|---|---|---|
| Tropical evergreen | Heavy rainfall: Western Ghats, the north-east, Andaman Islands | Rain all year, so leaves are not shed at once |
| Deciduous (monsoon) | Areas with a dry season | Shed leaves for part of the year to save water |
| Tropical thorn | Low rainfall, semi-arid: Rajasthan, parts of Gujarat | Cactus, acacia: thick stems, deep roots, small or spiny leaves |
| Montane | High mountains, where temperature falls with altitude | Belts: broad-leaved trees, then conifers, then alpine grasses |
| Mangrove | Tidal, salty coasts and deltas, e.g. the Sundarbans | Breathing roots, as the waterlogged soil has little oxygen |
| Protected area | Human activity |
|---|---|
| National park | Strictest protection; no hunting, grazing or private activity |
| Wildlife sanctuary | Some regulated human activity allowed |
| Biosphere reserve: core zone | Strict protection with minimal human disturbance |
| Biosphere reserve: buffer and transition zones | Limited research and sustainable activities |
- 1Most of the district's forest is lost to mining
- 2Rainfall becomes erratic
- 3Wells dry up and the soil erodes
- 4Tribal families migrate to cities for work
- Biodiversity
- The variety of living organisms in an area — the range of species, the genetic variation within them, and the ecosystems they form.
- Ecosystem
- A community of living organisms interacting with each other and with the non-living environment as a functioning unit.
- Flora and fauna
- The plant life and animal life of a region, shaped by its climate, relief and soil.
- Why biodiversity matters
- It supplies food, medicine, timber and fuel, keeps soil fertile, pollinates crops and regulates climate and water.
- Forests
- Large areas dominated by trees, which shelter most terrestrial biodiversity, hold soil in place and store great quantities of carbon.
- Types of forests in India
- Tropical evergreen, deciduous, thorn, montane and mangrove forests, each determined by rainfall, temperature and altitude.
- Forests and livelihoods
- Millions depend on forests for fuelwood, fodder, bamboo, honey, medicinal plants and grazing, and forest-dwelling communities most of all.
- Deforestation
- The clearing of forests for agriculture, mining, industry, dams and settlement, which destroys habitat and releases stored carbon.
- Consequences of habitat loss
- Species become endangered or extinct, soil erodes, groundwater falls and local rainfall patterns change.
- Endangered and extinct species
- An endangered species risks dying out; an extinct one has no living members. The Red Data Book records their status.
- Conservation
- The protection and careful management of natural resources so that they remain available to future generations.
- Protected areas
- National parks, wildlife sanctuaries and biosphere reserves set aside to conserve habitats, differing in how strictly human activity is limited.
- Community participation in conservation
- Joint forest management and community-conserved areas succeed because local people depend on the forest and know it best.
- Sustainable use
- Using resources at a rate at which they can renew themselves, so that present needs are met without denying those of the future.
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Life on Earth — FAQs
What are the key concepts in Class 9 Social Science Life on Earth?+
Life on earth is remarkably varied, and that variety is itself a resource. This chapter covers biodiversity and the ecosystems that sustain it, the forests that shelter much of it, the livelihoods that depend on them, and the case for conservation. Key ideas include Biodiversity, Ecosystem, Flora and fauna, Why biodiversity matters, Forests, Types of forests in India.
What does Class 9 Social Science Chapter 11 (Life on Earth) cover on XamBaaz?+
It has 78 NCERT-based MCQs on "Life on Earth": 25 Easy, 28 Medium and 25 Hard. Together they make 10 timed quizzes, and you never get the same set twice. Every question has an instant explanation. They help you prepare for CBSE Board exams.
Are these "Life on Earth" questions free to practise?+
Yes. Sign in with Google to practise "Life on Earth" free. Full unlimited access is ₹999/year. One year from the day you pay. You stay in Class 9 till 31 March; on 1 April your account moves up to Class 10 and the rest of your year carries over. No chapter is charged separately.
How should I revise "Life on Earth" for the exam?+
Start with the Easy quiz to check your basics, then try Medium and Hard to practise applying them. There are 10 timed quizzes on this chapter, so you can come back for a fresh set instead of one you have seen. Read each explanation, retry the questions you miss, and track your accuracy until it stays high.
Are these "Life on Earth" MCQs available with answers?+
Yes. 6 sample questions are on this page with answers: tap an option, or "Show answer", to see the correct option and a step-by-step explanation. Sign in free with Google to start practising, with instant scoring.
Is there negative marking in the "Life on Earth" quizzes?+
Yes. The timed quizzes use exam-style marking: +4 for a right answer, −1 for a wrong one and 0 for a skip. MHT-CET and CBSE board papers have no negative marking. Our mocks for those are scored their way.
What are the important questions from Life on Earth (Class 9 Social Science)?+
The questions that matter most test Biodiversity, Ecosystem, Flora and fauna, Why biodiversity matters, Forests, Types of forests in India. This page shows 6 solved important MCQs with answers and explanations. Sign in to practise all 78 questions on the chapter as timed quizzes.
Is there an online quiz for Life on Earth?+
Yes — Class 9 Social Science Life on Earth has timed online quizzes at Easy, Medium and Hard levels, with instant scoring and a worked explanation on every question. The first quiz on the chapter is free.
Are there question answers and extra questions for Life on Earth (Class 9 Social Science)?+
Yes. This page has 6 solved questions on Life on Earth, each with the correct answer and a short explanation. Sign in to practise all 78 questions on the chapter as timed quizzes.
Are there assertion–reason questions for Life on Earth (Class 9 Social Science)?+
Yes. The Life on Earth question bank has 4 assertion–reason questions in the CBSE board format, alongside the regular MCQs. Each comes with the answer and a worked explanation. Sign in to practise them in timed quizzes.