Home
Class 12
BIOLOGY
Study the graph given below and answer t...

Study the graph given below and answer the question that follow ?
(i) What is relationship between dissolved oxygen and biochemical oxygen Demand (BOD) ?
(ii) Mention their effect on aquatic life in the river.

Text Solution

Verified by Experts

(i) As BOD refers to the amount of oxygen consumed if all the organic matter in one liter of water were oxidised by bacteria. Thus greater the BOD, lesser will be the dissolved oxygen in sewage discharge.
(ii) Effects on aquatic life
(a) It causes high mortality rate aquatic animals.
(b) The excessive nutrients facilitate algel growth causing algal bloom .
Promotional Banner

Topper's Solved these Questions

  • XII BOARDS

    XII BOARDS PREVIOUS YEAR|Exercise DELHI BOARD 2016|1 Videos

  • XII BOARDS

    XII BOARDS PREVIOUS YEAR|Exercise [SET -I] [Comptt.] SECTION-A|4 Videos

  • XII BOARDS

    XII BOARDS PREVIOUS YEAR|Exercise [OUTSIDE DELHI : SET-III] SECTION - C|10 Videos

  • SAMPLE PAPER 2019

    XII BOARDS PREVIOUS YEAR|Exercise Section E Part B|3 Videos

Similar Questions

Explore conceptually related problems

Study the graph given below and choose the option that is correctly describing the relationship between dissolved oxygen (DO) and biochemical oxygen demand (BOD) :

Study the diagram given below and answer the following questions.

Biochemical Oxygen Demand (BOD) in a river water

What do you mean by Biochemical Oxygen Demand (BOD)?

Read the bar graph given below and answer the following questions: What information is given by the þar graph?

What effects does the increasing organic waste have on the dissolved oxygen content and biochemical oxygen demand of water?

Study the following graph carefully and answer the questions that What was the average of percent rise over the given years ?

XII BOARDS PREVIOUS YEAR-XII BOARDS-C.B.S.E. CLASS- XII
  1. Name the blank spaces a, b, c and d from the table given below :

    Text Solution

    |

  2. Name the type of immunity that is present at the time of birth in hume...

    Text Solution

    |

  3. Study the graph given below and answer the question that follow ? (i...

    Text Solution

    |

  4. Draw a labelled schematic structure of a transcription unit. Explain t...

    Text Solution

    |

  5. A snapdragon plant homezygous for red flower when crossed with a whit...

    Text Solution

    |

  6. Name any two vertebrate body parts that are homologous to human foreli...

    Text Solution

    |

  7. When and why do same animals like snails go into aestivation ?

    Text Solution

    |

  8. What is economic value of Spiurline ?

    Text Solution

    |

  9. What was the speciality of the milk produced by the transgenic cow Ros...

    Text Solution

    |

  10. How do neutrophils act as a cellular barrier to pathogens in humen ?

    Text Solution

    |

  11. Mention the polarity of DNA stands a - b and c -d shown in the replica...

    Text Solution

    |

  12. Mention any two significant roles predation plays in nature.

    Text Solution

    |

  13. Why is the polar region not a suitable habitat for tiny humming birds ...

    Text Solution

    |

  14. (i) Expand IUD. (ii) Why is hormone releasing IUD considered a good ...

    Text Solution

    |

  15. Name the interaction in each of the following : (a) Cuscute growing ...

    Text Solution

    |

  16. Apant of Antirrhinum majus with red flowers was crossed with another p...

    Text Solution

    |

  17. A women with blood group A married a men with B group . Show the possi...

    Text Solution

    |

  18. Why do sports persons of often fall a victim to cocaine addiction ?

    Text Solution

    |

  19. State the difference between the first trophic levels of detritus food...

    Text Solution

    |

  20. Coconut palm is monoecious while date palm is dioecious. Why are they ...

    Text Solution

    |