ENVIRONMENTAL SCIENCE
Paper – III
Note : This paper contains seventy five (75) objective type questions of two (2) marks each. All questions are compulsory.
1. Chemosynthesis involves CO2 fixation using energy derived from
(A) Sunlight
(B) Infrared radiation
(C) UV-radiation
(D) Inorganic and Organic compounds
2. Wind in the mountain-valley regions are of
(A) Microscale
(B) Mesoscale
(C) Macroscale
(D) Synoptic scale
3. In tropical region an aircraft is flying at an altitude of 10 km. At that altitude the temperature is – 40 °C. What is the ambient temperature on the ground ?
(A) 24 °C
(B) 40 °C
(C) 30 °C
(D) 20 °C
4. Assertion (A) : Upper atmosphere shields life on earth.
Reason (R) : Ultraviolet radiations are absorbed in the upper atmosphere.
Choose the correct answer :
Codes :
(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 and (R) is false.
(D) (A) is false and (R) is true.
5. The molar extinction coefficient of proline ninhydrin complex at 520 nm is 0.34 μM–1Cm–1. A solution of the proline ninhydrin complex has an absorbance of 0.68 in a one centimeter cuvette. The concentration (μM) of proline is
(A) 0.5
(B) 0.2312
(C) 2.312
(D) 2
6. The principal components of photochemical smog in urban areas are
(A) SO2 and NO2
(B) SPM and CO
(C) SPM and NO2
(D) Oxides of Nitrogen, Hydrocarbons and Ozone.
7. The amount of a particular gas dissolved in water depends on
(i) its solubility in water.
(ii) its partial pressure at the air/water interface or sediment/ water interface.
(iii) the water temperature.
(iv) the levels of salts in the water.
Identify the correct answer :
(A) (i) and (ii) only
(B) (ii), (iii) and (iv) only
(C) (i), (ii) and (iii) only
(D) (i), (ii), (iii) and (iv)
8. A 50 ml solution of pH = 1 is mixed with a 50 ml solution of pH = 2. The pH of the mixture will be nearly
(A) 0.76
(B) 1.26
(C) 1.76
(D) 2.26
9. The solubility product of the following type of reaction :
10. Cells grown in medium containing isotope sulphur 35 will show radio labelling in
(A) membrane lipids
(B) membrane proteins
(C) glycogen
(D) nucleic acid
11. A stream flowing at 10.0 m3/s has a tributary feeding it with a flow of 5.0 m3/s. The stream concentration of chloride upstream at the junction is 20.0 mg/L and the tributary chloride concentration is 40 mg/L. Treating chloride as a conservative substance and assuming complete mixing of the two streams, find the down stream concentration.
(A) 26.7 mg/L
(B) 30.2 mg/L
(C) 22.6 mg/L
(D) 35.2 mg/L
12. Assume that dilution factor p for an unseeded mixture of waste and water is 0.03. The DO of the mixture is initially 9.0 mg/L and after 5 days, it has dropped to 3.0 mg/L. The reaction rate constant ‘K’ has been found to be 0.22 / day. Five day BOD of the water will be
(A) 200 mg/L
(B) 150 mg/L
(C) 100 mg/L
(D) 75 mg/L
13. Nudation is generally caused by
(A) migration of species
(B) climate change
(C) invasion of foreign species
(D) modification of habitat
14. Which one of the following is the best tool to study the interacting residues in protein-ligand interaction ?
(A) X-ray crystallography
(B) Circular dichroism spectroscopy
(C) UV – Vis spectroscopy
(D) Fluorescence spectroscopy
15. During centrifugation, if the centrifugal force is FC, buoyant force is Fb, and frictional force is Ff, which of the following equations expresses the sedimentation of the molecule ?
16. Match the List – I with List – II and choose the correct answer from the given codes :
17. The earthworm used for composting is
(a) Crassiclitellata excavata
(b) Octochaetona serrata
(c) Lumbricus terrestris
(d) Eisenia foetida
Choose the correct answer :
(A) (a) and (b) only
(B) (b) and (d) only
(C) (b) and (c) only
(D) (a) and (d) only
18. The amount of the living material present in different trophic levels at a given time is called
(a) standing crop
(b) standing state
(c) biomass
(d) biosphe
Choose the correct answer :
(A) (a) and (c) are correct.
(B) (d) is correct.
(C) (b) is correct.
(D) (c) and (b) are correct.
19. Many orchids use trees as a surface to grow. This is an example of
(A) Commensalism
(B) Mutualism
(C) Parasitism
(D) Predation
20. The r– strategist is a
(A) small organism that has a short life, produces many offsprings and does not reach carrying capacity.
(B) small organism that has a longer life, produces offsprings and does not reach carrying capacity.
(C) small organism that has a short life, produces numerous offsprings and reach carrying capacity.
(D) medium organism that has a short life, produces numerous offsprings and reach carrying capacity.
21. Under the Rhino relocation project, during 1987, Rhinoes were introduced in
(A) Assam
(B) Meghalaya
(C) West Bengal
(D) Madhya Pradesh
22. Which of the following is an endangered bird species ?
(A) Kashmir stag
(B) Great Indian Bustard
(C) Hangul
(D) Black buck
23. In India, Crocodile breeding project started for the first time in
(A) Tamil Nadu
(B) West Bengal
(C) Odisha
(D) Goa
24. Identify the correct sequence of materials in terms of their porosity.
(A) Sand > clay > gravel
(B) Clay > sand > gravel
(C) Gravel > sand > clay
(D) Gravel > clay > sand
25. For an aquifer of gravel having cross sectional area of 4 m2 and a depth of 2.5 m, how much water could potentially be extracted ? (The porosity and specific yield of gravel are 25% and 20% respectively.)
(A) 0.5 m3
(B) 0.25 m3
(C) 0.125 m3
(D) 1 m3
26. The layers formed by thermal stratification in lakes are
(A) Epilimnion, Midlimnion, Hypolimnion
(B) Epilimnion, Oligolimnion, Hypolimnion
(C) Epilimnion, Dystrolimnion, Hypolimnion
(D) Epilimnion, Thermocline, Hypolimnion
27. On an aerial photograph, the focal length (f) of the camera lens is 6 inches and flying height (H) over the datum line is 15,000 ft. What is scale of the aerial photograph ?
(A) 1 : 30,000
(B) 1 : 10,000
(C) 1 : 5,000
(D) 1 : 25,000
28. Which of the following substrate will have highest reflectance value ?
(A) Silt loam with 20% moisture.
(B) Clay with 36% moisture.
(C) Silt loam with 0.8% moisture.
(D) Clay with 2% moisture.
29. Assertion (A) : For sustainable development of a region, proper land use planning is required.
Reason (R) : Land use planning involves inputs of soil types, rock types, seismicity, weather pattern and socio-economic conditions of a region.
Codes :
(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 and (R) is false.
(D) (A) is false and (R) is true.
30. Tundra is a biome characterized by
(A) stunted trees and permanently frozen sub-surface soil.
(B) coniferous trees and permanently frozen sub-surface soil.
(C) lack of trees and permanently frozen sub-surface soil.
(D) evergreen trees and permanently frozen sub-surface soil.
31. Acid mine drainage occurs when
(A) the combined action of O2, H2O and certain bacteria cause sulphur in coal to form H2SO4.
(B) the combined action of H2O and certain bacteria cause sulphur in coal to form H2SO4.
(C) the combined action of O2 and certain bacteria cause sulphur in coal to form H2SO4.
(D) the combined action of SO2 and certain bacteria with coal to form H2SO4.
32. In accordance with the Saffir – Simpson hurricane scale, a cyclonic storm of category 5 should have wind speeds
(A) > 69 ms–1
(B) 50 – 58 ms–1
(C) 59 – 69 ms–1
(D) 33 – 42 ms–1
33. Assertion (A) : Large scale OTEC development may not be good for environment.
Reason (R) : Release of CO2 from ocean depths into the atmosphere could exacerbate GHG effect.
Codes :
(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) Both (A) and (R) are false.
34. In a methane fuel cell, what will be the voltage of the cell and its efficiency ?
(Given : ΔG° = 8 × 105 Joules/gm – mole ΔH° = 8.8 × 105 Joules / gm – mole and Faraday’s constant = 96500 coulomb/ gm-mole)
(A) ~ 1.23 Volts, ~ 90.9%
(B) ~ 1.04 Volts, ~ 90.9%
(C) ~ 1.15 Volts, ~ 11%
(D) ~ 2.13 Volts, ~ 92%
35. The coefficient of performance for an ideal wind mill is
(A) 3/8
(B) 5/16
(C) 2/5
(D) 16/27
36. Assume that the energy released during the combustion of methane is 900 kJ/mol. Its carbon intensity is
(A) 13.3 gc/MJ
(B) 15.3 gc/MJ
(C) 19.7 gc/MJ
(D) 24.2 gc/MJ
37. In a nuclear fusion reactor it is envisaged to use a liquid blanket of Li to absorb fast neutrons from D+T reaction. How many neutrons are produced as a result of 
(A) 1
(B) 2
(C) 3
(D) 4
38. In an ideal MHD power plant, the electrical efficiency corresponding to maximum power production is
(A) 50%
(B) 75%
(C) 25%
(D) 100%
39. Energy intensity is a measure of
(A) effectiveness of energy utilisation
(B) energy produced per unit area
(C) energy produced per unit volume
(D) energy produced per unit area per unit time
40. One of the criteria for characterizing a region as ABC hotspot is that the annual mean anthropogenic Aerosol Optical Depth (AOD) is greater than
(A) 0.3
(B) 0.5
(C) 0.8
(D) 0.1
41. The resultant of two noise levels of 50 dB and 55 dB is
(A) 58 dB
(B) 55.41 dB
(C) 52.5 dB
(D) 56.19 dB
42. Which of the following is used as a coagulant for removal of phosphates in water ?
(A) Aluminium sulphate
(B) Iron sulphate
(C) Copper sulphate
(D) Potassium chromate
43. Which of the following radionuclides has the longest half-life ?
(A) C14
(B) Sr90
(C) I131
(D) Cs137
44. Under anaerobic conditions nitrogenase catalises
(A) breakdown of atmospheric nitrogen
(B) oxidation of atmospheric nitrogen
(C) reduction of atmospheric nitrogen
(D) hydrolysis of nitrogenous compounds
45. Size range of atmospheric aerosols is
(A) 5nm – 100μm
(B) 100μm – 150μm
(C) 150μm – 200μm
(D) 0.01nm – 5nm
46. Which one of the following is used as microbial indicator of water contamination ?
(A) Coliform bacteria
(B) Giardia
(C) Cryptosporidium
(D) Tobacco mosaic virus
47. Elevated salt and Na+ concentrations in soils are highly toxic to many plants, but relatively high tolerance level (to this toxicity) is seen in
(A) Sugarbeet
(B) Sugarcane
(C) Onion
(D) Lettuce
48. Which of the following hydrocarbons is emitted by vegetation ?
(A) Ocimene
(B) Xylene
(C) Acrolein
(D) 1, 3 – Pentadions
49. For particles of size > 5μm, the efficiency of cyclones can be as high as
(A) 50%
(B) 60%
(C) 80%
(D) 90%
50. Given the following parameters of a primary settling chamber :
Diameter = 50m, Depth = 2.5m, average detention time = 2 hours. How much quantity of waste water is being treated ?
(A) ~ 58928 m3/day
(B) ~ 48321 m3/day
(C) ~ 45321 m3/day
(D) ~ 25321 m3/day
51. A flat surface type electrostatic precipitator (ESP) has the following parameters : collector plate area A = 4600 m2, volumetric flow rate Q = 200 m3/s and effective drift velocity of flue gas = 0.15 m/s. What is the efficiency of the ESP ?
(A) ~ 0.968
(B) ~ 0.981
(C) ~ 0.975
(D) ~ 0.922
52. Assertion (A) : Cost-benefit analysis for assessment of natural systems is not merely concerned with the effects on environmental quality but seeks the conditions for sustainable use of the natural resources of a region.
Reason (R) : Cost-benefit analysis is not useful for small scale development projects, but is better suited for the analysis and evaluation of a regional development plan.
Identify the correct answer :
Codes :
(A) Both (A) and (R) are true and (R) is the correct explanation.
(B) Both (A) and (R) are true but (R) is not the correct explanation.
(C) (A) is true and (R) is wrong.
(D) Both (A) and (R) are wrong.
53. Battelle-Columbus weighting – scaling checklist methodology for water-resources projects obtains base line data on how many environmental parameters ?
(A) 40
(B) 78
(C) 68
(D) 50
54. Match List – I with List – II and choose the correct answer from the codes given below :
55. Match List – I with List – II and choose the correct answer from the codes given below :
56. Significant hazard/accident factor to be considered under risk assessment of distillaries are
(A) toxic gas release and human accident
(B) pressure wave and heat radiation
(C) toxic gas release and radiation
(D) pressure wave and toxic gas release
57. If ‘I’ is the impact of the population on the environment, ‘P’ is the size of the population, ‘A’ is the per capita affluence or consumption and ‘T’ is the damage caused by technologies, then which of the following equation is correct ?
(A) I = (P × A)/T
(B) I = P × A × T
(C) I = T/(P × A)
(D) I = P/(A × T)
58. According to Environment (Protection) Act, 1986 permissible limits of oil and grease in the effluents to be discharged into public sewers is
(A) 10 mg/l
(B) 20 mg/l
(C) 25 mg/l
(D) 30 mg/l
59. ‘Reed swamp stage’ is also referred to as
(A) submerged stage
(B) woodland stage
(C) rooted floated stage
(D) amphibious stage
60. Match List – I with List – II and choose the correct answer from the given codes :
61. Maximum energy content (KJ/kg) in a typical municipal solid waste is found in
(A) Plastic
(B) Leather
(C) Wood
(D) Textile
62. Public Liability Insurance Act was enacted in the year
(A) 1991
(B) 1993
(C) 1995
(D) 1997
63. A sample size of 17 observations is selected from a normal population with mean = 50. The sample mean and variance are 48 and 8 respectively. The value of t – statistic is
(A) 0.25
(B) – 2.82
(C) – 2.2
(D) 0.71
64. A class has equal number of boys and girls. The mean and standard deviation of their weights are 
Sg = 2 kg for girls and 
Sb = 2 kg for boys. What is the combined variance of the weights of the whole class ?
(A) 29
(B) 16
(C) 8
(D) 19
65. For a simple regression analysis involving the dependent variable Y and explanatory variable X, the following data is given :
No. of observations N = 40, ∑X2 = 2000, ∑Y2 = 2000, 
standard error of estimate of Y
on X, SYX = 4. The explained variance is
(A) 360
(B) 860
(C) 500
(D) 580
66. A Ψ2 distribution with 10 degrees of freedom has variance
(A) 10
(B) 20
(C) 5
(D) 40
67. The rank of the matrix 
(A) 2
(B) 3
(C) 1
(D) Not possible to determine.
68. Which of the following is not an eigenvector of the matrix 
?
69. Assertion (A) : Ground level concentration of pollutants decreases when taller stacks are used.
Reason (R) : The ground level concentration varies inversely proportional to the height of the stacks.
Codes :
(A) Both (A) and (R) are correct and (R) is the correct explanation of (A).
(B) Both (A) and (R) are correct, but (R) is not the correct explanation of (A).
(C) (A) is true and (R) is false.
(D) Both (A) and (R) are false.
70. Assume that 5.3 billion people live in less developed countries, where average birth rate is 23 and infant mortality rate is 53. Then the total death due to infant mortality are
(A) 6.5 × 106/year
(B) 5.3 × 106/year
(C) 7.3 × 106/year
(D) 8.5 × 106/year
71. Which of the following act as ‘natural sink for carbon’ ?
I. Trees
II. Oceans
III. Soils
Choose the correct code :
(A) I only
(B) I and II only
(C) I, II and III
(D) II and III only
72. Match List – I with List – II and choose the correct answer from the codes given below:
73. REDD+ initiatives include
I. Forest carbon partnership facility
II. Forest investment programme
III. Sanitation for all
IV. Food security for all
Choose the correct code :
(A) I and IV only
(B) I and II only
(C) I, II and III only
(D) III and IV only
74. Match List – I with List – II and choose the correct answer from the codes given below:
75. Identify the correct sequence with reference to sensitization about environmental problems.
(A) Knowledge → Awareness → Attitude → Skill → Evaluation ability → Participation
(B) Knowledge → Awareness → Skill → Attitude → Participation → Evaluation ability
(C) Awareness → Knowledge → Attitude → Skill → Evaluation ability → Participation
(D) Awareness → Knowledge → Participation → Attitude → Skill → Evaluation ability
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