Chapter 15 · Our Environment

NCERT Exemplar Class 10 Science Chapter 15 Multiple Choice Questions

All 21 questions of NCERT Exemplar Class 10 Science Chapter 15 Multiple Choice Questions (Our Environment), in the book's order, each with its answer and a step-by-step solution.

1. Q1
   Which one ​of the ​following ​is an ​artificial ecosystem?

   1. (a)Pond
   2. (b)Crop field
   3. (c)Lake
   4. (d)Forest
   Show answer

   (b) Crop field

   Step-by-step solution →
2. Q2
   In a food ​chain, ​the ​third ​trophic level ​is always ​occupied by

   1. (a)carnivores
   2. (b)herbivores
   3. (c)decomposers
   4. (d)producers
   Show answer

   (a) carnivores

   Step-by-step solution →
3. Q3
   An ecosystem includes

   1. (a)all living organisms
   2. (b)non-living objects
   3. (c)both living organisms and non-living objects
   4. (d)sometimes living organisms and sometimes non-living objects
   Show answer

   (c) both living organisms and non-living objects

   Step-by-step solution →
4. Q4
   In ​the ​given food chain, ​suppose the amount of ​energy at fourth trophic level is 5 kJ, what will be the energy ​available at ​the producer level? Grass → ​Grasshopper → Frog → Snake → Hawk

   1. (a)$5$ kJ
   2. (b)$50$ kJ
   3. (c)$500$ kJ
   4. (d)$5000$ kJ
   Show answer

   (d) $5000$ kJ

   Step-by-step solution →
5. Q5
   Accumulation ​of non-biodegradable ​pesticides in the ​food chain ​in increasing amount at ​each higher trophic ​level is ​known as

   1. (a)eutrophication
   2. (b)pollution
   3. (c)biomagnification
   4. (d)accumulation
   Show answer

   (c) biomagnification

   Step-by-step solution →
6. Q6
   Depletion ​of ozone ​is mainly ​due ​to

   1. (a)chlorofluorocarbon compounds
   2. (b)carbon monoxide
   3. (c)methane
   4. (d)pesticides
   Show answer

   (a) chlorofluorocarbon compounds

   Step-by-step solution →
7. Q7
   Organisms ​which synthesise ​carbohydrates from ​inorganic compounds ​using ​radiant energy are called

   1. (a)decomposers
   2. (b)producers
   3. (c)herbivores
   4. (d)carnivores
   Show answer

   (b) producers

   Step-by-step solution →
8. Q8
   In ​an ecosystem, the ​10% of energy ​available for ​transfer from ​one trophic ​level ​to the next is in the form of

   1. (a)heat energy
   2. (b)light energy
   3. (c)chemical energy
   4. (d)mechanical energy
   Show answer

   (c) chemical energy

   Step-by-step solution →
9. Q9
   Organisms ​of ​a higher ​trophic ​level which ​feed on several types of organisms belonging ​to a lower ​trophic level ​constitute the

   1. (a)food web
   2. (b)ecological pyramid
   3. (c)ecosystem
   4. (d)food chain
   Show answer

   (a) food web

   Step-by-step solution →
10. Q10
    Flow ​of energy in ​an ecosystem ​is always

    1. (a)unidirectional
    2. (b)bidirectional
    3. (c)multi directional
    4. (d)no specific direction
    Show answer

    (a) unidirectional

    Step-by-step solution →
11. Q11
    Excessive exposure ​of ​humans to U ​V-rays ​results in

    1. (i)damage to immune ​system
    2. (ii)​damage to lungs
    3. (iii)skin cancer
    4. (iv)peptic ulcers

    1. (a)(i) and (ii)
    2. (b)(ii) and (iv)
    3. (c)(i) and (iii)
    4. (d)(iii) and (iv)
    Show answer

    (c) (i) and (iii)

    Step-by-step solution →
12. Q12
    In the following groups of materials, which group (s) ​contains ​only ​non-biodegradable items?

    1. (i)​Wood, ​paper, ​leather
    2. (ii)Polythene, detergent, PVC
    3. (iii)Plastic, detergent, ​grass
    4. (iv)Plastic, bakelite, DDT

    1. (a)(iii)
    2. (b)(iv)
    3. (c)(i) and (iii)
    4. (d)(ii) and (iv)
    Show answer

    (d) (ii) and (iv)

    Step-by-step solution →
13. Q13
    Which of ​the following ​limits ​the number of ​trophic levels ​in a ​food ​chain?

    1. (a)Decrease in energy at higher trophic levels
    2. (b)Dufficient food supply
    3. (c)Polluted air
    4. (d)Water
    Show answer

    (a) Decrease in energy at higher trophic levels

    Step-by-step solution →
14. Q14
    Which ​of the ​statement ​is incorrect?

    1. (a)All green plants and blue green algae are producers
    2. (b)Green plants get their food from organic compounds
    3. (c)Producers prepare their own food from inorganic compounds
    4. (d)Plants convert solar energy into chemical energy
    Show answer

    (b) Green plants get their food from organic compounds

    Step-by-step solution →
15. Q15
    Which group of ​organisms ​are not constituents of a food chain?

    1. (i)Grass, lion, rabbit, wolf
    2. (ii)Plankton, man, fish, ​grasshopper
    3. (iii)Wolf, grass, snake, ​tiger
    4. (iv)​Frog, ​snake, eagle, ​grass, grasshopper

    1. (a)(i) and (iii)
    2. (b)(iii) and (iv)
    3. (c)(ii) and (iii)
    4. (d)(i) and (iv)
    Show answer

    (c) (ii) and (iii)

    Step-by-step solution →
16. Q16
    The percentage of ​solar ​radiation ​absorbed by all the green plants ​for the ​process of ​photosynthesis ​is about

    1. (a)$1$ %
    2. (b)$5$ %
    3. (c)$8$ %
    4. (d)$10$ %
    Show answer

    (a) $1$ %

    Step-by-step solution →
17. Q17
    In the ​given Figure 15.1 the ​various trophic levels are shown in ​a pyramid. ​At which trophic level is maximum ​energy ​available?

    1. (a)$T_4$
    2. (b)$T_2$
    3. (c)$T_1$
    4. (d)$T_3$
    Show answer

    (c) $T_1$

    Step-by-step solution →
18. Q18
    What will ​happen if deer is ​missing ​in the food chain given ​below? Grass → ​Deer ​→ ​Tiger

    1. (a)The population of tiger increases
    2. (b)The population of grass decreases
    3. (c)Tiger will start eating grass
    4. (d)The population of tiger decreases and the population of grass increases
    Show answer

    (d) The population of tiger decreases and the population of grass increases

    Step-by-step solution →
19. Q19
    The decomposers in an ecosystem

    1. (a)convert inorganic material, to simpler forms
    2. (b)convert organic material to inorganic forms
    3. (c)convert inorganic materials into organic compounds
    4. (d)do not breakdown organic compounds
    Show answer

    (b) convert organic material to inorganic forms

    Step-by-step solution →
20. Q20
    If ​a grass hopper is ​eaten ​by ​a ​frog, then the energy transfer will be from

    1. (a)producer to decomposer
    2. (b)producer to primary consumer
    3. (c)primary consumer to secondary consumer
    4. (d)secondary consumer to primary consumer
    Show answer

    (c) primary consumer to secondary consumer

    Step-by-step solution →
21. Q21
    Disposable ​plastic ​plates should ​not ​be ​used because

    1. (a)they are made of materials with light weight
    2. (b)they are made of toxic materials
    3. (c)they are made of biodegradable materials
    4. (d)they are made of non-biodegradable materials
    Show answer

    (d) they are made of non-biodegradable materials

    Step-by-step solution →