Our Environment

Science Mcqs

Our Environment 

Q1.Which of the following is biodegradable waste?
(a) DDT
(b) Aluminium can
(c) Plastic bag
(d) Cow dung

Ans: (d) Cow dung

Q2. Which of the two sets belong to the same trophic level?
(a) Rabbit: Tiger
(b) Vulture : Rat
(c) Grasshopper : Hawk
(d) Frog : Lizard

Ans: (d) Frog: Lizard

Q3. In a given food chain if the amount of energy at the fourth trophic level is 6 kJ, what will be the energy available at the producer level?
(a) 6000 kJ
(b) 20 kJ
(c) 60 kJ
(d) 600 kJ

Ans: (a) 6000 kJ

Q4. Which of the following is the best way for disposal of vegetable and fruit peels?
(a) Landfill
(b) Recycling
(c) Composting
(d) Burning

Ans: (c) Composting

Q5. The problem caused due to ozone hole is
(a) earthquakes
(b) damage due to UV radiations
(c) chemical pollution
(d) acid rain

Ans: (b) damage due to UV radiations

Q6. An ecosystem includes
(a) all living organisms
(b) non-living objects
(c) both living organisms and non-living objects
(d) sometimes living organisms and sometimes non-living objects

Ans: (c) both living organisms and non-living objects

Q7. Accumulation of non-biodegradable pesticides in the food chain in increasing amount at each higher trophic level is known as
(a) eutrophication
(b) pollution
(c) biomagnification
(d) accumulation

Ans: (c) biomagnification

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Q8. In an ecosystem, the 10% of energy available for transfer from one trophic level to the next is in the form of
(a) heat energy
(b) light energy
(c) chemical energy
(d) mechanical energy

Ans: (c) chemical energy

Q9. Organisms which synthesise carbohydrates from inorganic compounds using radiant energy are called
(a) decomposers
(b) producers
(c) herbivores
(d) carnivores

Ans: (b) producers

Q10. Excessive exposure of humans to UV-rays results in
(i) damage to immune system
(ii) damage to lungs
(iii) skin cancer
(iv) peptic ulcers
(a) (i) and (ii)
(b) (ii) and (iv)
(c) (i) and (iii)
(d) (iii) and (iv)

Ans: (c) (i) and (iii)

Q11. Organisms of a higher trophic level which feed on several types of organisms belonging to a lower trophic level constitute the
(a) food web
(b) ecological pyramid
(c) ecosystem
(d) food chain

Ans: (a) food web

Q12. Which group of organisms are not the constituents of a food chain?

(i) Grass, lion, rabbit, wolf
(ii) Plankton, man, fish, grasshopper
(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)

Ans: (c) (ii) and (iii)

Q13. The percentage of solar radiation absorbed by all the green plants for the process of photosynthesis is about
(a) 1%
(b) 5%
(c) 8%
(d) 10%

Ans: (a) 1%

Q14. Which of the statements is incorrect?
(а) All green plants and blue green algae are producers
(b) Green plants get their food from organic compounds
(c) Producers prepare their own food from inorganic compounds
(d) Plants convert solar energy into chemical energy

Ans: (b) Green plants get their food from organic compounds

Q15. The decomposers in an ecosystem
(a) convert inorganic material, to simpler forms
(b) convert organic material to inorganic forms
(c) convert inorganic materials into organic compounds
(d) do not breakdown organic compounds

Ans: (b) convert organic material to inorganic forms

Q16. Disposable plastic plates should not be used because
(а) they are made of materials with light weight
(b) they are made of toxic materials
(c) they are made of biodegradable materials
(d) they are made of non-biodegradable materials

Ans: (d) they are made of non-biodegradable materials

Q17. What will happen if deer is missing in the food chain given below?
Grass → Deer → Tiger
(а) The population of tiger increases
(b) The population of grass decreases
(c) Tiger will start eating grass
(d) The population of tiger decreases and the population of grass increases

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

Q18. When is the world environment day celebrated?
(a) 16 June
(b) 5 December
(c) 5 June
(d) 5 July

Ans: (c) 5 June

Q19. Which of these is a greenhouse gas?
(a) Hydrogen sulphide
(b) Methane
(c) Ozone
(d) Carbon monoxide

Ans: (b) Methane

Q20. The transfer of energy in a food chain is always:
(a) Unidirectional
(b) Methane
(c) Bi-directional
(d) Random

Ans: (a) Unidirectional

Q21. Which of these organisms are the most important decomposers in an ecosystem?
(a) Algae and fungi
(b) Fungi and bacteria
(c) Algae and bacteria
(d) Bacteria and virus

Ans: (b) Fungi and bacteria

Q22. Which of these does not belong to biotic component?
(a) Parasites
(b) Fungi
(c) Bacteria
(d) Soil

Ans: (d) Soil