Life on Earth — Class 9 MCQs with Answers
Class 9 CBSE Social Science · Chapter 11
72 practice questions · 24 Easy · 24 Medium · 24 Hard · Updated
Practise the most important Class 9 CBSE Social Science questions from Chapter 11, "Life on Earth". You get 9 timed quizzes made from 72 NCERT-based MCQs, with answers and explanations. The questions are split into 24 Easy, 24 Medium and 24 Hard. Warm up on the basics, then move on to the exam-level questions that set top scorers in CBSE Board exams apart.
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 trains you to stay accurate under time pressure, 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. 14 sample questions are solved in full below, with the answer and a worked explanation. Sign in free to start practising.
Key concepts: Life on Earth (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.
- 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.
Life on Earth — important questions & MCQs with answers (Class 9 Social Science)
14 solved questions from this chapter's difficulty levels, each with its answer and explanation. The other 58 are timed and scored when you sign in.
- Q1Easy
The term 'biodiversity' refers to:
A.The amount of rainfall in a regionB.The variety of all living organisms on Earth✓ CorrectC.The number of rivers in a countryD.The total area covered by oceansAnswer: B. 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.
- Q2Easy
The natural plant cover of a region that has grown on its own is called:
A.PlantationB.CropC.Natural vegetation✓ CorrectD.GardenAnswer: C. Natural vegetation
Explanation: Natural vegetation is the plant life that grows naturally in a region without human help, suited to its climate and soil.
- Q3Easy
Protecting and managing forests and wildlife so they survive for the future is called:
A.DeforestationB.Conservation✓ CorrectC.PoachingD.MiningAnswer: B. Conservation
Explanation: Conservation means the careful protection and wise use of natural resources so they are available for future generations.
- Q4Easy
People who depend directly on forests for food, fuel and shelter are often called:
A.IndustrialistsB.TouristsC.Forest-dependent communities✓ CorrectD.TradersAnswer: C. Forest-dependent communities
Explanation: Many tribal and rural groups are forest-dependent communities who rely on forests for their daily needs and livelihood.
- Q5Easy
Which of the following is NOT a level of biodiversity?
A.Mineral diversity✓ CorrectB.Species diversityC.Ecosystem diversityD.Genetic diversityAnswer: A. Mineral diversity
Explanation: Biodiversity is studied at three levels — genetic, species and ecosystem. 'Mineral diversity' is not a level of biodiversity.
- Q6Easy
Mangrove forests in India are mainly found in:
A.The Thar DesertB.The Himalayan peaksC.The Deccan PlateauD.Coastal and delta areas like the Sundarbans✓ CorrectAnswer: D. Coastal and delta areas like the Sundarbans
Explanation: Mangroves grow in tidal, salty coastal and delta regions such as the Sundarbans of West Bengal.
- Q7Medium
Two tigers in the same forest look slightly different in size, colour and stripe pattern. This kind of variety is an example of:
A.Ecosystem diversityB.Species diversityC.Genetic diversity✓ CorrectD.Climate diversityAnswer: C. Genetic diversity
Explanation: Differences among individuals of the same species are due to genetic diversity — variation in genes within a species.
- Q8Medium
Trees in tropical evergreen forests rarely shed all their leaves at once mainly because:
A.The soil is frozenB.The region has a long dry seasonC.Rainfall is high throughout the year, so there is no need to save water✓ CorrectD.There is no sunlightAnswer: C. Rainfall is high throughout the year, so there is no need to save water
Explanation: Abundant rainfall all year means these trees never face water shortage, so they stay green and do not shed leaves at one time.
- Q9Medium
Which is the MAIN difference between a national park and a wildlife sanctuary?
A.There is no difference at allB.A national park has no animalsC.A sanctuary is only for plantsD.A sanctuary allows some regulated human activity, while a national park has stricter protection✓ CorrectAnswer: D. 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.
- Q10Medium
Forest-dependent communities are often the best protectors of forests because:
A.They want to clear the forest quicklyB.They prefer living in citiesC.They never use the forestD.Their livelihood depends on the forest, so they use its resources sustainably✓ CorrectAnswer: D. Their livelihood depends on the forest, so they use its resources sustainably
Explanation: Since their daily survival depends on the forest, these communities have a strong interest in protecting and using it sustainably.
- Q11Medium
In the food chain grass → grasshopper → frog → snake, the frog acts as a:
A.DecomposerB.Primary consumerC.ProducerD.Secondary consumer✓ CorrectAnswer: D. Secondary consumer
Explanation: The grasshopper (eating grass) is the primary consumer; the frog that eats the grasshopper is the secondary consumer.
- Q12Hard
A wheat crop disease wipes out almost an entire harvest because all the plants were genetically identical. This situation best demonstrates that:
A.Genetic diversity within a species increases the risk of diseaseB.Diseases cannot affect cropsC.Low genetic diversity makes a species more vulnerable to being wiped out✓ CorrectD.Ecosystem diversity is the only thing that mattersAnswer: C. 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.
- Q13Hard
Two regions lie at the same latitude, but one has dense evergreen forest and the other has thorn scrub. The MOST likely reason for this difference is:
A.Difference in the length of the dayB.Difference in the amount of rainfall they receive✓ CorrectC.Difference in the colour of the soil onlyD.Difference in the number of people living thereAnswer: B. Difference in the amount of rainfall they receive
Explanation: At the same latitude, rainfall is the key control on vegetation — high rainfall supports evergreen forest, low rainfall supports thorn scrub.
- Q14Hard
Project Tiger protects not only tigers but an entire ecosystem. The BEST explanation for this is that the tiger is a:
A.Species that lives only in waterB.Producer at the base of the food chainC.Decomposer that recycles nutrientsD.Top predator whose protection requires healthy prey and habitat below it✓ CorrectAnswer: D. Top predator whose protection requires healthy prey and habitat below it
Explanation: As a top predator, the tiger needs abundant prey and intact forest, so saving it means protecting the whole ecosystem it depends on.
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Start this chapter free →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.
What does Class 9 Social Science Chapter 11 (Life on Earth) cover on XamBaaz?+
It has 72 NCERT-based MCQs on "Life on Earth": 24 Easy, 24 Medium and 24 Hard. Together they make 9 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 on a launch offer until 1 December 2026. 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 9 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. 14 sample questions are shown here in full, each with the correct option and a step-by-step "Why" 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. This page shows 14 solved important MCQs with answers and explanations; all 72 questions on the chapter are available as timed quizzes once you sign in.
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.