11. With reference to a fresh water lake, consider the following characteristics
    1. Richness in nutrients
    2. Rapid turnover of phytoplankton
    3. Depletion of dissolved oxygen
    Which of the above is / are observed in a lake after its eutrophication ?

1. 1. 1 only

   
   
   

   2. 1 and 2

   
   
   

   3. 3 only

   
   
   

   4. 1, 2 and 3

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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12. Due to their extensive rice cultivation, some regions may be contributing to global warming. To what possible reason / reasons is this attributable ?
    1. The anaerobic conditions associated with rice cultivation cause the emission of methane.
    2. When nitrogen based fertilizers are used, nitrous oxide is emitted from the cultivated soil.
    Which of the statements given above is / are correct ?

1. 1. 1 only

   
   
   

   2. 2 only

   
   
   

   3. Both 1 and 2

   
   
   

   4. Neither 1 nor 2

   
   
   

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   NA

   Correct Option: C

   NA

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13. What is eutrophication ?

1. 1. Process by which organisms concentrate certain chemical substances to levels above those found in their natural environment

   
   
   

   2. Excessive growth of algae in nutrient-rich water leading to reduced oxygen levels and the death of many organisms

   
   
   

   3. The ability of organisms in a food chain to convert energy received into living matter

   
   
   

   4. Population explosion of species in an ecosystem due to the removal of their predators

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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14. The following forms of relationship exist between man and his environment according to the development of geographical thought
    1. Environmental determinism
    2. Possibilism
    3. Neo-determinism
    The correct sequence of the development of these forms of relationship is

1. 1. 2,1,3

   
   
   

   2. 3,1,2

   
   
   

   3. 1,3,2

   
   
   

   4. 1,2,3

   
   
   

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   NA

   Correct Option: D

   NA

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15. Consider the following which can be found in the ambient atmosphere
    1. Soot
    2. Sulphur hexagluoride
    3. Water vapour
    Which of the above contribute to the warming up of the atmosphere ?

1. 1. 1 and 2 only
      

   
   
   

   2. 3 only

   
   
   

   3. 2 and 3 only

   
   
   

   4. 1, 2 and 3

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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