CBSE Class 10 Biology Our Environment MCQs

Question : Food web is
(a) Food served through websites
(b) Display of different food items
(c) Using food items for a fashion dress
(d) Interlinked food chains
Answer : D

Question : Identify the proper food chain
(a) Grass, insect , frog , snake
(b) Grass , frog , insect , snake
(c) Insect , frog , grass , snake
(d) Grass , frog , snake , insect
Answer : A

Question : In a terrestrial ecosystem the biomass of ____________ should be the most
(a) Producer
(b) Herbivore
(c) Carnivore
(d) Any one of the above
Answer : A

Question : Which one of the following is a non- biodegradable substance
(a) Manure
(b) Paper
(c) DDT
(d) Cotton cloth
Answer : C

Question. In the following groups of materials, which group(s) contains only non biodegradable items?
I. Wood, paper, leather
II. Polythene, detergent, PVC
III. Plastic, detergent, grass
IV. Plastic, bakelite, DDT
(a) III
(b) IV
(c) I and III
(d) II and IV
Answer : D

Question. Complete the given analogy. Non-biodegradable : _________ :: Biodegradable : Livestock wastes
(a) Cotton
(b) Grass
(c) Glass
(d) Orange peel
Answer : C

Question. Which of the following is an abiotic component of an ecosystem?
(a) Bacteria
(b) Plants
(c) Fungi
(d) Humus
Answer : D

Question. According to Charles Elton, which is not correct?
(a) Carnivores at the top of the pyramid.
(b) Producers at the top of the pyramid.
(c) Energy trapping is high at the top of the pyramid.
(d) Both (b) and (c)
Answer : D

Question. Now-a-days, which type of cups are being generally used in trains for serving tea/coffee/ soup etc. on daily basis?
(a) Washable glass cups
(b) Washable plastic cups
(c) Disposable paper cups
(d) Disposable cups made of plastic
Answer : C

Question. Minamata disease is due to
(a) MIC gas
(b) methyl mercury
(c) lead nitrate
(d) cobalt chloride.
Answer : B

Question. Which of the following statements is incorrect?
(a) A food chain is always straight.
(b) Producers belong to second trophic levels.
(c) Top carnivore are fourth order consumers.
(d) Consumers obtain organic nutrients from outside as food.
Answer : B

Question. Shorter food chains provide
(a) more energy
(b) less energy
(c) same energy
(d) any of these.
Answer : A

Question. Fish that feeds on zooplanktons is a
(a) primary consumer
(b) secondary consumer
(c) tertiary consumer
(d) decomposer.
Answer : B

Question. Ozone layer is essential because it absorbs most of the
(a) infrared radiations
(b) solar radiations
(c) ultraviolet radiations
(d) both (a) and (b).

Answer : C

Question. As it travels along the food chains, the concentration of DDT
(a) increases
(b) remains constant
(c) decreases
(d) fluctuates randomly.
Answer : A

Question. Select the incorrect statement.
(a) Food we eat is digested by various enzymes in our body.
(b) Non-biodegradable substances are not broken down by biological processes.
(c) All enzymes have same action on each substance.
(d) Plastics cannot be broken down by the action of bacteria and other saprophytes.
Answer : C

Question. In a grazing food chain, primary consumers (herbivores) represent 
(a) T1 level
(b) T2 level
(c) T3 level
(d) T4 level.
Answer : B

Question. Which of the following statements regarding solid wastes is correct?
(a) Change in the packaging technology has resulted in generation of lot of solid wastes.
(b) Dumping of solid wastes could reduce the fertility of the soil leading to reduction in crop yield.
(c) Accumulation of solid waste could cause increased incidents of disease in a locality.
(d) All of these.
Answer : D

Question. Incineration and pyrolysis are two methods of waste disposal done at high temperature. The two differs from each other as in later
(a) aerobic burning occurs
(b) chemical energy and chemical constituents are recovered
(c) ashes are the end products
(d) medical wastes are burnt with clinkers as the end product.
Answer : B

Question. Food web helps in
(a) providing alternative pathways of food availability 
(b) checking the overpopulation
(c) ecosystem stability
(d) all of these.
Answer : D

Question. In the given figure, the various trophic levels are shown in a pyramid. At which trophic level is maximum energy available?
(a) T₄
(b) T₂
(c) T₁
(d) T₃
Answer : C

Question. Green house gas produced by incomplete decomposition by anaerobic methanogens is
(a) CH₄
(b) CFCs
(c) CO₂
(d) N₂O
Answer : A

Question. The thinning of ozone layer was first observed in
(a) 1980s
(b) 1950s
(c) 1940s
(d) 1990s.
Answer : A

Question. Which group of organisms together do not constitute a food chain?
I . Grass, lion, rabbit, wolf
II. Plankton, man, hawk
III. Wolf, grass, snake, tiger
IV. Frog, snake, eagle, grass, grasshopper
(a) I and III
(b) III and IV
(c) II and III
(d) I and IV
Answer : C

Question. Of the total amount of energy that passes from one trophic level to another in a food chain, about 10% is
(a) transpired
(b) burnt in respiration
(c) stored in body tissues
(d) lost as heat.
Answer : C

Question. Which of the following groups contain nonbiodegradable substances only?
(a) Flowers, crops, plastic
(b) Plastic, polythene bags, aluminium cans
(c) Grass, wood, glass
(d) Fruit and vegetable peels, grass, wood
Answer : B

Question. Which of the following does not help in protecting our environment?
(a) Crop rotation
(b) Treatment of sewage
(c) Deforestation
(d) Judicious use of fertilisers
Answer : C

Question. DDT was accidently added to the water of a lake. All the organisms in it would be affected by DDT. Which of the following organisms would be affected the most?
(a) Man
(b) Birds living in the lake
(c) Fish living in the lake
(d) Aquatic plants in the lake
Answer : A

Question. Burning of waste substances usually in anaerobic conditions at high temperature of about 670°C is called
(a) land filling
(b) composting
(c) incineration
(d) none of these.
Answer : D

Question. If there was no CO₂ in the atmosphere, the earth’s temperature would be
(a) less than the present temperature
(b) same as the present temperature
(c) higher than the present temperature
(d) dependent on O₂ content of air.
Answer : A

Question. Select the mismatched pair.
(a) Crop field – Natural ecosystem
(b) Garden – Man made ecosystem
(c) Temperature – Abiotic factor
(d) Grass – Transducer
Answer : A

Question. Select the odd one out.
(a) Tomato leaves
(b) Wood
(c) Synthetic polymers
(d) Lime juice
Answer : C

Question. Which of the following pyramids is always upright?
(a) Pyramid of energy
(b) Pyramid of biomas
(c) Pyramid of numbers
(d) None of these
Answer : A

Question. Which of the following belongs to the category of primary consumers?
(a) Eagle and snake
(b) Grasshopper and cattle
(c) Snake and frog
(d) Water beetle and fish
Answer : B

Question :  World Environment day is celebrated on
(a) July 1
(b) July 5
(c) June 5
(d) June 1
Answer :  C

Question :  The UV radiation from the sun is likely to cause _____________ in human
(a) Skin cancer
(b) Lung cancer
(c) Liver Cancer
(d) Brain Cancer
Answer :  A

Question :  Accumulation of non- biodegradable pesticides in different trophic levels is called
(a) Biological magnification
(b) Biological degradation
(c) Biological concentration
(d) Biological deposition
Answer :  A

Question :  Only ____ % of the energy can be transferred from one trophic level to the next trophic level.
(a) 1
(b) 10
(c) 5
(d) 20
Answer :  B

Question :  The best way to dispose waste is by
(a) Separating biodegradable and nonbiodegradable waste before disposing in bins
(b) Making a paste of all domestic waste and putting them in a river
(c) Throw the waste on road side
(d) Dumping all domestic waste in litter bin
Answer :  A

Question :  Replacing Plastic cups by paper cups for selling tea on train may be preferred because
(a) Paper cups are bio degradable
(b) Paper cups are non bio degradable
(c) Paper cups are cheaper
(d) Plastic cups are bio degradable
Answer :  A

Fill In The Blank

Question. The hierarchies within a food web are called .......... levels.
Answer : Trophic

Question. Gardens and crop fields are examples of .......... 
Answer : Artificial Ecosystem

Question. Because there is a loss of energy at each trophic level ......... biomass can be supported at each successive level.
Answer : Less

Question. The flow of energy is always ......... in food chains.
Answer : Unidirectional

Question. The contamination of air by adding gases, smoke and ash is called ..........
Answer : Pollution

Question. Decrease in ozone in stratosphere is linked to release of synthetic chemicals like ..........
Answer : Chlorofluorocarbons

Question. The amount of various chemical materials cycling through the biosphere more or less remains .......... .
Answer : Constant

Question. All the interacting organisms in an area together with the non-living constituents of the environment form an ..........
Answer : Ecosystem

Question. Improvement in life style often results in increased generation of ......... material.
Answer : Waste

Question. The .......... make the energy from sunlight available to the rest of the ecosystem.
Answer : Producers

Question. The various populations of living organisms in an area together form .......... .
Answer : Biotic community

Question. The two important functions that food chains depict are transfer of .......... and ......... .
Answer : Energy, materials

Question. .......... absorb UV rays and protect the earth.
Answer : Ozone layer

Question. ......... is defined as sum total of all conditions and influences that affect the life of organisms.
Answer : Environment

Question. .......... absorb UV rays and protect the earth.
Answer : Ozone layer

Question. All the ecosystems taken together in a geographical area form a bigger unit known as.
Answer : Biome

Question. Climate refers to the prevailing .......... conditions.
Answer : Weather

Assertion & Reasoning Based MCQs

(a) Both assertion and reason are true, and reason is correct explanation of the assertion.
(b) Both assertion and reason are true, but reason is not the correct explanation of the assertion.
(c) Assertion is true, but reason is false.
(d) Assertion is false, but reason is true.

Question. Assertion : The burning of substances at higher temperature to form ash is called incineration.
Reason : Incineration greatly reduces the volume of waste.
Answer : B

Question. Assertion : We live in troposphere.
Reason : Our atmosphere extends beyond troposphere also.
Answer : B

Question. Assertion : Ozone depletion can be reduced by limiting the use of air conditioners and refrigerators.
Reason : Air conditioner and refrigerators release chlorofluorocarbons in the atmosphere that destroy ozone.
Answer : A

Question. Assertion : Pyramid of biomass may be upright or inverted.
Reason : Pyramid showing total biomass produced per unit time is always upright.
Answer : B

Question. Assertion : If pesticide is present in water bodies then fish eating birds accumulate maximum amount of DDT in their bodies.
Reason : Pesticides are not metabolised within bodies of living organisms and get concentrated at each trophic level leading to bioaccumulation.
Answer : A

Question. Assertion : There is always an interaction between neighbouring or distant ecosystems.
Reason : An ecosystem is recognised as self - regulating and self - sustaining entity.
Answer : B

Question. Assertion : Using jute bags while shopping is more environment friendly as compared to polythene bags.
Reason : Jute is biodegradable whereas polythene bag is non-biodegradable.
Answer : A

Question. Assertion : A food chain comprises of producers and consumers.
Reason : Consumers can be herbivores, carnivores and omnivores.
Answer : B

Question. Assertion : Paper cups are better option than plastic cups for serving tea.
Reason : Paper cups are biodegradable and can even be disposed off by burning.
Answer : A

Question. Assertion : Man is a social and cultured animal.
Reason : He developed socio-cultural environment and lives in it.
Answer : A

Matching Questions

DIRECTION : Each question contains statements given in two columns which have to be matched. Statements (A, B, C, D) in column-I have to be matched with statements (p, q, r, s) in column II.

Question.

Answer : A-p- B-q, C-r, D-s

Question.

Answer : A-r, B-s, C-p, D-q

Question.

Answer : A-s, B-r, C-q, D-p

Question.

Answer : A-w, B-s, C-u, D-v, E-p, F-q, G-r, H-t

Question.

Answer : A-r, B-s, C-p, D-q