Home
Class 12
BIOLOGY
Why does the oxygen concentration in the...

Why does the oxygen concentration in the water decrease when sewae is discharged into a river?

A

Due to microbial activity

B

Increase in the number of fish

C

Less oxygen absorbed from the air

D

Rapid growth of bacteria

Text Solution

Verified by Experts

The correct Answer is:
A
Promotional Banner

Topper's Solved these Questions

  • ENVIRONMENTAL ISSUES

    ARIHANT NEET|Exercise Chapter exercises (B) Medical entrances special format questions (Statement based questions)|4 Videos

  • ENVIRONMENTAL ISSUES

    ARIHANT NEET|Exercise Chapter exercises (B) Medical entrances special format questions (Matching)|5 Videos

  • ENVIRONMENTAL ISSUES

    ARIHANT NEET|Exercise Check point 26.4|15 Videos

  • ECOSYSTEM

    ARIHANT NEET|Exercise Exercises C Medical entrances gallery (collection of questions Asked in NEET & Various Medical Entrance Exams)|77 Videos

  • EVIDENCES OF EVOLUTION

    ARIHANT NEET|Exercise Chapter exercises (Medical entrances gallery)(Collection of questions Asked in NEET & Various Medical Entrance Exams )|58 Videos

Similar Questions

Explore conceptually related problems

Salinity in ocean water decreases when:

Explain the change that can be observed in the characterstics of river water when sewage is discharged into it and a few weeks after the discharge with respect to (i) level of dissolved oxygen (ii) Population of fresh water organisms.

At high oxygen concentration, the rate of photosynthesis decreases due to

Why does the electric field inside a dielectric decrease when it is placed in an external field ?

ARIHANT NEET-ENVIRONMENTAL ISSUES-Chapter exercises (A) Taking it together (Assorted Questions of the Chapter for Advanced Level Practice)
  1. Fly ash is environmental pollutant produced by

    Text Solution

    |

  2. Most harmful type of environmental pollutants are

    Text Solution

    |

  3. Which process does not result in the return of carbon dioxide to the a...

    Text Solution

    |

  4. Which air pollutant could cause rains to be acidic?

    Text Solution

    |

  5. Why does the oxygen concentration in the water decrease when sewae is ...

    Text Solution

    |

  6. Ozone hole is the

    Text Solution

    |

  7. Which of the following statements is incorrect?

    Text Solution

    |

  8. How human activities increased the supply of fixed nitrogen available ...

    Text Solution

    |

  9. Which of the following is not thought to be a possible consequence of ...

    Text Solution

    |

  10. Ozone is

    Text Solution

    |

  11. The destruction of the ozone layer is most directly linked to the

    Text Solution

    |

  12. Eutrophication in lakes is the direct result of

    Text Solution

    |

  13. Which of these show a result of deforestation and its effect on the en...

    Text Solution

    |

  14. What is a long-term effect of cutting down larger areas of rainforests...

    Text Solution

    |

  15. Some possible properties of modern insecticides are listed below. When...

    Text Solution

    |

  16. A lake has been polluted by sewage. Compared with unpolluted water, th...

    Text Solution

    |

  17. The table shows the oxygen level, numbers of green plants and of fish ...

    Text Solution

    |

  18. In pollution, the term 'synergism' is used for

    Text Solution

    |

  19. Ecological balance of a mining area is restored through

    Text Solution

    |

  20. Lichens are organisms, which are very sensitive to air pollution. The ...

    Text Solution

    |