Self Studies
Self Studies
Self Studies
Self Studies
Selfstudy
Selfstudy

Environmental Issues Test - 36

Result Self Studies

Environmental Issues Test - 36
  • Score

    -

    out of -
  • Rank

    -

    out of -
TIME Taken - -
Self Studies

SHARING IS CARING

If our Website helped you a little, then kindly spread our voice using Social Networks. Spread our word to your readers, friends, teachers, students & all those close ones who deserve to know what you know now.

Self Studies Self Studies
Weekly Quiz Competition
  • Question 1
    1 / -0
    For how long and at what temperature an experiment is run to determine the value of BOD of a water body? 
    Solution
    BOD or biochemical oxygen demand is the amount of dissolved oxygen which is required by the aerobic organisms during the decomposition of organic matter. The BOD is measured at a specific temperature and specific period of time. BOD value is represented in the form of oxygen which is consumed per litre of the sample used for testing. The sample is tested before and after 5 days of incubation at 20 °C. The value describes the amount of organic material present in the contaminated or waste water. 
    Thus, the correct answer is option B. 
  • Question 2
    1 / -0
    Effect of today's radioactive fall out will be more on future children than on present-day children as
    Solution
    The ionising radiations from the radioactive materials results in causing mutations in the children. The children which are born toady may not suffer from the disorder. But when the children are born in the future generations due to the passing of the mutations from the parents in the recessive forms, the disorder will be expressed. The mutations which are caused by the radiations are generally recessive and expressed when both the genes are in the recessive form. 
    Thus, the correct answer is option B. 
  • Question 3
    1 / -0
    Which of the following is the most dangerous environment hazard to mankind? 
    Solution
    Nuclear winter is the climatic effects of nuclear war. It is the damaging effects of the light, heat, blast, and radiation caused by a nuclear explosion. Smoke from the fires started by nuclear weapons will be heated by the sun. They will rise in the upper stratosphere, and spread globally resulting in thick black clouds that could block out fraction of the sun’s light for a period as long as several weeks that would cause the surface temperatures would plunge for a few weeks. Hence semidarkness, killing frosts, and subfreezing temperatures, combined with high doses of radiation would stop plant photosynthesis. This will destroy earth’s vegetation and animal life. Hence a nuclear war could thus reduce human population to a very low number. Thus the correct answer is option C.
  • Question 4
    1 / -0
    Addition of phosphates and nitrates or fertilizers into water leads to
    Solution
    Eutrophication is the natural aging of a lake by nutrient enrichment of its water. With time, streams draining the sewage pollutants and fertilizers into the lake introduce nutrients such as nitrogen and phosphorus, which encourage the growth of aquatic organisms. As the lake's fertility increases, algal bloom occurs. Algal bloom causes the deterioration of water quality and fish mortality and dead remains begin to be deposited on the lake bottom. Over the year, the lake is finally converted into the land. 
    Thus, the correct answer is option B. 
  • Question 5
    1 / -0
    When huge amount of CO$$_2$$ is dumped into a river, the BOD will
    Solution
    Biological Oxygen Demand is a measurement of the amount of dissolved oxygen that is used by aerobic microorganisms when decomposing organic matter in water.  It is expressed in milligrams of oxygen consumed per liter of the sample during 5 days of incubation at 20°C and is used to determine the degree of organic pollution of water. Hence when a huge amount of carbon dioxide is added BOD will not be affected. Thus, the correct answer is option C.
  • Question 6
    1 / -0
    A rapid growth of photosynthetic algae in water develops 'bloom'. How would it affect the environment of water?
  • Question 7
    1 / -0
    Air pollution is maximum by
    Solution
    Automobiles and industries release huge amounts of gases by burning fossil fuels. Those gases are the combination of hydrocarbons (toxic compound of hydrogen & carbon), nitrogen oxides, carbon dioxide, sulphur dioxide, etc.

    And such gases affect ozone layer parallel to the air pollution. Thus, air pollution is maximum caused by automobile exhausts and chemicals from industries.  

    Hence, option A is correct .
  • Question 8
    1 / -0
    Increase skin cancer and higher mutation rates are generally the consequences of
    Solution
    The ozone layer is present in the stratosphere above the Earth. The layer of ozone is responsible for the absorption of the harmful ultraviolet radiations from the solar radiations. Due to ozone depletion, these radiations enter the Earth's atmosphere and cause skin cancer. The radiations can also damage the eye and other exposed parts of the body. The radiations can also cause mutations like thymine dimer formation or breaking of the hydrogen bonds. 
    Thus, the correct answer is option B. 
  • Question 9
    1 / -0
    Which of the following chemical is released by chlorofluorocarbon that is harmful to ozone ?
    Solution
    Chlorofluorocarbons are the compounds which are used as coolants in the air conditioning systems, refrigerators, coolers, etc. The CFCs, when released into the atmosphere, react with UV rays to form chlorine atoms which destroy the ozone layer and results in the thinning out of the ozone layer also known as the ozone hole.
    Thus, the correct answer is option D. 
  • Question 10
    1 / -0
    The measurement of rate of oxygen utilisation by a unit volume of water over a period of time is to measure.
    Solution
    BOD or Biochemical oxygen demand is the amount of dissolved oxygen which is required by the aerobic organisms during the decomposition of organic matter. The BOD is measured at a specific temperature and specific period of time. BOD value is represented in the form of oxygen which is consumed per litre of the sample used for testing. The sample is tested before and after 5 days of incubation at 20 °C. The value describes the amount of organic material present in the contaminated or waste water. 
    Thus, the correct answer is option A. 
Self Studies
User
Question Analysis

  • Correct -

  • Wrong -

  • Skipped -

My Perfomance
  • Score

    -

    out of -
  • Rank

    -

    out of -
Re-Attempt Weekly Quiz Competition
Self Studies Get latest Exam Updates
& Study Material Alerts!
No, Thanks
Self Studies
Click on Allow to receive notifications
Allow Notification
Self Studies
Self Studies Self Studies
To enable notifications follow this 2 steps:
  • First Click on Secure Icon Self Studies
  • Second click on the toggle icon
Allow Notification
Get latest Exam Updates & FREE Study Material Alerts!
Self Studies ×
Open Now