Multiple Choice Questions (MCQs) for Class 10 Science: Chapter 13 Our Environment
Access targeted multiple-choice questions for Chapter 13 Our Environment designed to align with the latest CBSE academic syllabus for Class 10 Science. These objective practice sets help students evaluate their conceptual understanding and improve exam readiness.
Practice Chapter 13 Our Environment MCQs for Class 10 Science
Access the complete set of multiple-choice questions for Chapter 13 Our Environment below. This focused format allows students to isolate specific topics for thorough review and uninterrupted practice alongside official CBSE textbooks.
This set of 40 multiple choice questions for CBSE Class 10 Science covers Our Environment, with answers and step-wise explanations for every question. It tests ecosystems, biotic and abiotic components, producers, consumers and decomposers, food chains, and the ozone layer.
Multiple Choice Questions
(a) Paper
(b) Torn clothes
(c) Metallic and plastic discards
(d) All the above
Show Answer & Explanation
Answer: (d) All the above
Explanation:
1. Paper, torn clothes and metallic or plastic discards can all be sent for recycling.
2. Paper can be pulped and reused, rags can be reprocessed, and metals and plastics can be melted and remoulded.
Teacher's Note:
1. Recycling turns used material into new products.
2. Segregating waste at home makes recycling much easier.
(a) primary consumers
(b) secondary and tertiary consumers
(c) reducers
(d) zooplankton.
Show Answer & Explanation
Answer: (b) secondary and tertiary consumers
Explanation:
1. Carnivores are the secondary and tertiary consumers.
2. Herbivores are primary consumers; the animals that eat herbivores or other carnivores are secondary and tertiary consumers.
Teacher's Note:
1. Consumers are grouped by what they eat.
2. Carnivores sit at the third and fourth trophic levels.
(a) grass, wheat and mango
(b) grass, goat and human
(c) goat, cow and elephant
(d) grass, fish and goat
Show Answer & Explanation
Answer: (b) grass, goat and human
Explanation:
1. Grass, goat and human show who eats whom in order.
2. A food chain must be a linear feeding sequence. Grass is eaten by the goat, and the goat by a human.
Teacher's Note:
1. Check that each organism eats the one before it.
2. Mango and wheat are both producers, so they cannot form a chain together.
A. Food chain, B. Food web, C. Heterotrophs, D. Autotrophs, E. Carnivore, F. Herbivore
I. An organism that eats meat. II. An organism that eats plants. III. An organism that makes its food from light or chemical energy. IV. An organism that gets its energy by eating other organisms. V. The sequence of organisms of who eats whom in a biological community. VI. The network of all the interrelated food chains in a biological community.
(a) A – V; B – VI; C – IV; D – III; E – I; F – II
(b) A – VI; B – IV; C – III; D – I; E – II; F – V
(c) A – III; B – I; C – II; D – V; E – VI; F – IV
(d) A – II, B – V; C – VI; D – IV; E – III; F – I
Show Answer & Explanation
Answer: (a) A – V; B – VI; C – IV; D – III; E – I; F – II
Explanation:
1. A food chain is who eats whom, a food web is a network, and so on.
2. Food chain = V, food web = VI, heterotrophs = IV, autotrophs = III, carnivore = I, herbivore = II, which is option (a).
Teacher's Note:
1. Match one term at a time and cross out options.
2. Learn the basic terms precisely.
(I) Energy transfer in the biotic world always proceeds from the autotrophs.
(II) Energy flow is unidirectional.
(III) Energy availability is maximum at the tertiary level.
(IV) There is loss of energy from one trophic level to the other.
Select the relevant statements for the forest ecosystem
(a) I, II and IV
(b) I, II and III
(c) I, III and IV
(d) II, III and IV
Show Answer & Explanation
Answer: (a) I, II and IV
Explanation:
1. Statements I, II and IV are true; III is false.
2. Energy starts from autotrophs, is unidirectional and is lost at each step; availability is maximum at the producer level, not the tertiary level.
Teacher's Note:
1. Check each statement separately.
2. Energy availability falls as we go up.
(a) Because plants are easily grown
(b) Because plants are nutritious
(c) Because plants can produce its own energy
(d) Because plants do not require energy
Show Answer & Explanation
Answer: (c) Because plants can produce its own energy
Explanation:
1. Plants produce their own food, so every chain begins with them.
2. Only plants can capture solar energy and make food; all consumers depend on this energy.
Teacher's Note:
1. Producers start the chain.
2. Without them there is no energy input.
(a) Mountains
(b) Rocks
(c) Grass
(d) All of these
Show Answer & Explanation
Answer: (c) Grass
Explanation:
1. Grass is a living thing, so it is a biotic factor.
2. Mountains and rocks are non-living; grass is a living producer.
Teacher's Note:
1. Biotic means living.
2. Abiotic means non-living.
(a) 1%
(b) 5%
(c) 8%
(d) 10%
Show Answer & Explanation
Answer: (a) 1%
Explanation:
1. Plants absorb only about 1% of the solar radiation for photosynthesis.
2. Only about 1% of the sunlight falling on leaves is converted into food energy.
Teacher's Note:
1. Memorise this number.
2. The 10% law is a different fact.
(i) Grass, lion, rabbit, wolf
(ii) Plankton, man, fish, grasshopper
(iii) Wolf, grass, snake, tiger
(iv) Frog, snake, eagle, grass, grasshopper
(a) (i), (iii)
(b) (iii), (iv)
(c) (ii), (iii)
(d) (i), (iv)
Show Answer & Explanation
Answer: (c) (ii), (iii)
Explanation:
1. Group (ii) has man with a grasshopper and plankton; group (iii) has no herbivore.
2. A proper food chain needs a producer, herbivore and carnivore in a feeding relation; groups (ii) and (iii) do not form such chains.
Teacher's Note:
1. Test each group for a link of who eats whom.
2. A chain with no herbivore is broken.
(a) Phytoplanktons → Zooplanktons → Fish
(b) Seed grains → Rodents → Eagle
(c) Grass → Insects → Frog → Snake
(d) Seaweed → Zooplanktons → Phytoplanktons
Show Answer & Explanation
Answer: (d) Seaweed → Zooplanktons → Phytoplanktons
Explanation:
1. Seaweed and phytoplankton are producers and should come first.
2. Zooplankton eat phytoplankton, so phytoplankton cannot come after zooplankton.
Teacher's Note:
1. Producers must start the chain.
2. Check the arrows.
Ozone is both harmful and beneficial because it is ___________.
(a) not poisonous to the ecosystem
(b) poisonous but not for humans
(c) poisonous in very high amounts, and its concentration is very low in the atmosphere
(d) poisonous to humans but it also prevents UV rays from entering into the earth’s atmosphere
Show Answer & Explanation
Answer: (d) poisonous to humans but it also prevents UV rays from entering into the earth’s atmosphere
Explanation:
1. Ozone is poisonous to humans but protects us from UV.
2. Ozone near the ground is harmful, but in the stratosphere it blocks UV rays.
Teacher's Note:
1. Ozone is good up high, bad close to the ground.
2. It is both harmful and beneficial.
(i) UV rays are needed for the formation of the ozone layer in the upper atmosphere.
(ii) UV rays are less active and inside the atmosphere, they become activated due to the other atmospheric contents.
(iii) In the upper atmosphere, UV rays have less energy and are not harmful and form the part of the atmosphere.
(a) Only (i)
(b) Only (ii)
(c) Only (iii)
(d) Both (i) and (iii)
Show Answer & Explanation
Answer: (a) Only (i)
Explanation:
1. UV rays form the ozone layer in the upper atmosphere.
2. Only statement (i) is right: UV rays split oxygen so ozone can form.
Teacher's Note:
1. UV is helpful in the stratosphere.
2. It is harmful at ground level.
Assertion (A): The flow of energy is unidirectional.
Reason (R): Energy as it progresses through the various trophic levels is no longer available to the previous level.
(a) Both A and R are true, and R is the correct explanation of A.
(b) Both A and R are true, but R is not the correct explanation of A.
(c) A is true, but R is false.
(d) A is false, but R is true.
Show Answer & Explanation
Answer: (a) Both A and R are true, and R is the correct explanation of A.
Explanation:
1. Energy is not available to the previous level, so flow is one-way.
2. Both statements are true and the reason explains the assertion.
Teacher's Note:
1. Link cause and effect.
2. The reason supports the assertion.
(a) saprophytes
(b) parasites
(c) producers
(d) none of these
Show Answer & Explanation
Answer: (c) producers
Explanation:
1. Every food chain begins with producers.
2. Producers capture energy first and pass it to consumers.
Teacher's Note:
1. The base of a chain is the producer.
2. Parasites and saprophytes are not producers.
(a) Religious practices
(b) Change in packaging style and products
(c) Home cooking
(d) Use of plant-based products
Show Answer & Explanation
Answer: (b) Change in packaging style and products
Explanation:
1. Changes in packaging and products increased waste.
2. Packaging has shifted to non-biodegradable materials, so waste has increased.
Teacher's Note:
1. Lifestyle changes create more waste.
2. Plastic packs are a big contributor.
(a) River—Natural ecosystem
(b) Air—Biotic component
(c) Crop field—Artificial ecosystem
(d) Water—Abiotic component
Show Answer & Explanation
Answer: (b) Air—Biotic component
Explanation:
1. Air is an abiotic, not biotic, component.
2. Air is non-living, so air–biotic is incorrect.
Teacher's Note:
1. Biotic means living.
2. River, crop field and water pairs are right.
Assertion (A): Biotic components of an ecosystem include all the living organisms present in that ecosystem.
Reason (R): Biotic components also include wind, gases, light, etc.
(a) Both A and R are true, and R is the correct explanation of A.
(b) Both A and R are true, but R is not the correct explanation of A.
(c) A is true, but R is false.
(d) A is false, but R is true.
Show Answer & Explanation
Answer: (c) A is true, but R is false.
Explanation:
1. Biotic components are living; wind and light are abiotic.
2. The assertion is true, but the reason is false.
Teacher's Note:
1. Check both statements.
2. Wind and light are non-living.
(a) By recycling
(b) By burning
(c) By disposing them in water bodies
(d) By mixing with biodegradable waste
Show Answer & Explanation
Answer: (a) By recycling
Explanation:
1. Recycling is the safe way to handle non-biodegradable waste.
2. Burning and dumping in water cause pollution.
Teacher's Note:
1. Reduce, reuse, recycle.
2. Never mix wastes.
Assertion (A): Biodegradable domestic wastes can be buried in a pit, dug into ground.
Reason (R): They are converted into compost and used as manure.
(a) Both A and R are true, and R is the correct explanation of A.
(b) Both A and R are true, but R is not the correct explanation of A.
(c) A is true, but R is false.
(d) A is false, but R is true.
Show Answer & Explanation
Answer: (a) Both A and R are true, and R is the correct explanation of A.
Explanation:
1. Biodegradable waste buried in a pit becomes compost.
2. Both statements are true, and the reason explains the assertion.
Teacher's Note:
1. Composting gives manure.
2. Use kitchen waste well.
Phytoplankton → Krill → Small fish → Tuna → Shark
(a) Phytoplankton
(b) Krill
(c) Tuna
(d) Shark
Show Answer & Explanation
Answer: (d) Shark
Explanation:
1. The shark is at the top, so it has the most pollutant.
2. Chemicals accumulate along the chain.
Teacher's Note:
1. Top predator wins.
2. Count the arrows.
Assertion (A): Improvements in our lifestyle have resulted in lesser amounts of waste material generation.
Reason (R): Changes in packaging have resulted in much of the waste generated to be non-biodegradable.
(a) Both A and R are true, and R is the correct explanation of A.
(b) Both A and R are true, but R is not the correct explanation of A.
(c) A is true, but R is false.
(d) A is false, but R is true.
Show Answer & Explanation
Answer: (d) A is false, but R is true.
Explanation:
1. Lifestyle improvements increase waste.
2. The assertion is false; the reason is true.
Teacher's Note:
1. Better lifestyle brings more waste.
2. Packaging is non-biodegradable.
Assertion (A): All kitchen waste cannot form compost.
Reason (R): Material like milk packets may not be biodegradable.
(a) Both A and R are true, and R is the correct explanation of A.
(b) Both A and R are true, but R is not the correct explanation of A.
(c) A is true, but R is false.
(d) A is false, but R is true.
Show Answer & Explanation
Answer: (a) Both A and R are true, and R is the correct explanation of A.
Explanation:
1. Milk packets are not biodegradable, so not all kitchen waste forms compost.
2. Both statements are true and the reason explains the assertion.
Teacher's Note:
1. Segregate waste.
2. Only organic waste is composted.
Assertion (A): The concentration of harmful chemicals is least in human beings.
Reason (R): Man is at the apex of the food chain.
(a) Both A and R are true, and R is the correct explanation of A.
(b) Both A and R are true, but R is not the correct explanation of A.
(c) A is true, but R is false.
(d) A is false, but R is true.
Show Answer & Explanation
Answer: (d) A is false, but R is true.
Explanation:
1. Man has the highest concentration of harmful chemicals.
2. The assertion is false; the reason is true because man is at the top.
Teacher's Note:
1. Biomagnification is highest at the top.
2. Humans are top consumers.
(a) Eagle and snake
(b) Grasshopper and cattle
(c) Snake and frog
(d) Water beetle and fish
Show Answer & Explanation
Answer: (b) Grasshopper and cattle
Explanation:
1. Grasshoppers and cattle eat plants, so they are primary consumers.
2. Eagles, snakes and frogs eat animals.
Teacher's Note:
1. Primary consumers are herbivores.
2. Check the diet.
(a) T1 level
(b) T2 level
(c) T3 level
(d) T4 level.
Show Answer & Explanation
Answer: (b) T2 level
Explanation:
1. Herbivores are at the second trophic level.
2. Producers are T1, herbivores T2.
Teacher's Note:
1. Count from producers.
2. Primary consumers are herbivores.
(a) Flowers, crops, plastic
(b) Plastic, polythene bags, aluminium cans
(c) Grass, wood, glass
(d) Fruit and vegetable peels, grass, wood
Show Answer & Explanation
Answer: (b) Plastic, polythene bags, aluminium cans
Explanation:
1. Plastic, polythene bags and aluminium cans are non-biodegradable.
2. The other groups include flowers, grass, wood or peels.
Teacher's Note:
1. Look for all-artificial items.
2. Every item must be non-degradable.
Assertion (A): Using jute bags while shopping is more environment friendly as compared to polythene bags.
Reason (R): Jute is biodegradable whereas polythene bag is non-biodegradable.
(a) Both A and R are true, and R is the correct explanation of A.
(b) Both A and R are true, but R is not the correct explanation of A.
(c) A is true, but R is false.
(d) A is false, but R is true.
Show Answer & Explanation
Answer: (a) Both A and R are true, and R is the correct explanation of A.
Explanation:
1. Jute is biodegradable and polythene is not.
2. Both statements are true and the reason explains the assertion.
Teacher's Note:
1. Use jute bags.
2. Avoid polythene.
(a) infrared
(b) ultraviolet ray
(c) X-ray
(d) gamma ray
Show Answer & Explanation
Answer: (b) ultraviolet ray
Explanation:
1. Ozone absorbs ultraviolet rays.
2. UV is high-energy radiation.
Teacher's Note:
1. Ozone is the shield.
2. UV harms living things.
Assertion (A): Aquariums are known as the man-made ecosystems.
Reason (R): Aquariums are created and maintained by humans.
(a) Both A and R are true, and R is the correct explanation of A.
(b) Both A and R are true, but R is not the correct explanation of A.
(c) A is true, but R is false.
(d) A is false, but R is true.
Show Answer & Explanation
Answer: (a) Both A and R are true, and R is the correct explanation of A.
Explanation:
1. Aquariums are man-made ecosystems because humans create and maintain them.
2. Both are true and the reason explains the assertion.
Teacher's Note:
1. Artificial ecosystems need care.
2. Natural ones do not.
Column-I: (P) Consists of three atoms of oxygen, (Q) Main cause of depletion of ozone layer, (R) Second trophic level, (S) Break-down of dead organic compounds
Column-II: (i) CFCs, (ii) Decomposers, (iii) Ozone, (iv) Herbivore
(a) P-(iii), Q-(i), R-(iv), S-(ii)
(b) P-(i), Q-(iii), R-(iv), S-(ii)
(c) P-(i), Q-(iii), R-(ii), S-(iv)
(d) P-(i), Q-(ii), R-(iii), S-(iv)
Show Answer & Explanation
Answer: (a) P-(iii), Q-(i), R-(iv), S-(ii)
Explanation:
1. Ozone has three oxygen atoms; CFCs deplete it; herbivore is the second level; decomposers break down dead matter.
2. P-iii, Q-i, R-iv, S-ii.
Teacher's Note:
1. Match one by one.
2. Eliminate wrong options.
(a) 1%
(b) 5%
(c) 10%
(d) 50%
Show Answer & Explanation
Answer: (c) 10%
Explanation:
1. About 10% of energy is transferred.
2. This is the 10% law.
Teacher's Note:
1. Remember 10%.
2. 90% is lost.
(a) herbivores
(b) carnivores
(c) omnivores
(d) autotrophs
Show Answer & Explanation
Answer: (d) autotrophs
Explanation:
1. Autotrophs are at the first trophic level.
2. They are producers.
Teacher's Note:
1. Level 1 is producers.
2. Herbivores are level 2.
Grass → Grasshopper → Frog → Snake → Hawk
(a) 36 kJ
(b) 30 kJ
(c) 900 kJ
(d) 3000 kJ
Show Answer & Explanation
Answer: (d) 3000 kJ
Explanation:
1. Multiply by 10 at each step down: 3, 30, 300, 3000 kJ.
2. The producer has 3000 kJ.
Teacher's Note:
1. Work backwards.
2. Multiply by 10.
(a) Bio-absorption
(b) Bio-translocation
(c) Biomagnification
(d) Bio-multiplication
Show Answer & Explanation
Answer: (c) Biomagnification
Explanation:
1. The pesticide rose in concentration up the chain, which is biomagnification.
2. Soil 0.1, grains 1, birds 2 mg.
Teacher's Note:
1. Rising amounts show magnification.
2. Not absorption.
(a) Biological calcification
(b) Biological nitrification
(c) Biological magnification
(d) Biological oxidation
Show Answer & Explanation
Answer: (c) Biological magnification
Explanation:
1. DDT levels rise with trophic level: biological magnification.
2. The terms calcification, nitrification and oxidation are different.
Teacher's Note:
1. Magnification is increase.
2. Learn it.
(a) Food chain
(b) Food web
(c) Ecosystem
(d) None of these
Show Answer & Explanation
Answer: (c) Ecosystem
Explanation:
1. Interacting organisms with non-living parts form an ecosystem.
2. A food chain is only feeding.
Teacher's Note:
1. Define ecosystem.
2. It includes abiotic parts.
(a) Consumers
(b) Producers
(c) Decomposers
(d) None of these
Show Answer & Explanation
Answer: (c) Decomposers
Explanation:
1. Decomposers return simple inorganic substances to the soil.
2. Plants use them again.
Teacher's Note:
1. Decomposers recycle.
2. Bacteria and fungi.
(a) 1, 10, 10
(b) 90, 10, 10
(c) 1, 1, 1
(d) 1, 10, 0
Show Answer & Explanation
Answer: (a) 1, 10, 10
Explanation:
1. Plants capture about 1% of sunlight, then 10% and 10%.
2. The percentages are 1, 10, 10.
Teacher's Note:
1. Learn the sequence.
2. 1, then 10.
(a) cataract
(b) skin cancer
(c) Decrease immunity
(d) Respiratory troubles
Show Answer & Explanation
Answer: (d) Respiratory troubles
Explanation:
1. Respiratory troubles are not caused by ozone depletion.
2. Cataract, skin cancer and low immunity are.
Teacher's Note:
1. Know the effects.
2. UV related.
(a) Grass → Rabbit → Snake → Eagle
(b) Grass → Goat → Fox → Lion
(c) Goat → Grass → Elephant → Snake
(d) Grass → Wheat → Frog → Goat
Show Answer & Explanation
Answer: (a) Grass → Rabbit → Snake → Eagle
Explanation:
1. Grass, rabbit, snake and eagle follow a feeding order.
2. Other options break the order.
Teacher's Note:
1. Check order.
2. Producer first.
Free study material for Science
Chapter 13 Our Environment Objective Questions & Solutions for Class 10 Science
Download Multiple Choice Questions: Chapter 13 Our Environment (Class 10 Science)
Explore reliable practice questions for Chapter 13 Our Environment tailored for Class 10 Science learners. Use these multiple-choice formats to evaluate preparedness and strengthen problem-solving skills.
Concept Clarification for Chapter 13 Our Environment
Cross-reference your completed choices with comprehensive NCERT solutions for Class 10 Science to ensure absolute clarity across all sub-topics in this chapter.
Additional Study Resources for Class 10 Science
Wrap up your chapter revision by testing your knowledge against standard question formats. Everything on our platform is provided free of charge.
FAQs
You can get most exhaustive CBSE Class 10 Biology Our Environment MCQs Set 09 for free on StudiesToday.com. These MCQs for Class 10 Science are updated for the 2026-27 academic session as per CBSE examination standards.
Yes, our CBSE Class 10 Biology Our Environment MCQs Set 09 include the latest type of questions, such as Assertion-Reasoning and Case-based MCQs. 50% of the CBSE paper is now competency-based.
By solving our CBSE Class 10 Biology Our Environment MCQs Set 09, Class 10 students can improve their accuracy and speed which is important as objective questions provide a chance to secure 100% marks in the Science.
Yes, Science MCQs for Class 10 have answer key and brief explanations to help students understand logic behind the correct option as its important for 2026 competency-focused CBSE exams.
Yes, you can also access online interactive tests for CBSE Class 10 Biology Our Environment MCQs Set 09 on StudiesToday.com as they provide instant answers and score to help you track your progress in Science.