Environmental Studies · General Awareness

Water Quality and Pollution

1,303 Questions

Water Quality and Pollution examines the sources, mechanisms, and impacts of contaminants in aquatic ecosystems. It covers crucial environmental concepts like eutrophication, biochemical oxygen demand, and thermal pollution. This subject frequently appears in general science and environmental studies sections of various examinations.

Eutrophication CausesThermal Pollution EffectsBiochemical Oxygen DemandSynthetic Fertilizer ImpactsWastewater SourcesAquatic Ecosystem Toxicity

Water Quality and Pollution Questions

Multiple choice zoology diseases and immunity basics of water pollution sewage treatment wastewater treatment - need and methods personal and public cleanliness who will do this?

Excess nitrates in water cause problems for the Chesapeake Bay because

  1. They cause excessive cellular respiration in plants and animals, resulting in a large amount of carbon dioxide production.

  2. They cause excessive bacteria growth resulting in too much oxygen which hurts photosynthesis in plants.

  3. They cause excessive algae growth, blocking sunlight and reducing oxygen when the algae dies.

  4. Nitrates are poisonous to fish, crabs, and oysters.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Excess nitrates from runoff lead to eutrophication, causing rapid algae growth. When this algae dies, its decomposition by bacteria consumes dissolved oxygen, creating hypoxic conditions that harm aquatic life.

Multiple choice zoology diseases and immunity basics of water pollution sewage treatment wastewater treatment - need and methods personal and public cleanliness who will do this?

Mark the correct statement about nitrification


(a) Nitrification is important is agricultural system.
(b) Nitrification increase nitrogen leaching.
(c) Plays important role in removal of nitrogen from municipal waste water.

  1. a, b, c

  2. a, b

  3. a, c

  4. b, c
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Nitrification is a biological oxidation process includes convertion of Ammonia to Nitrate increases nitrogen leaching because nitrate is more water soluble than Ammonia.

Multiple choice zoology ecosystems decomposition in ecosystem ecosystem productivity and decomposition producers, consumers and decomposers

The slow rate of decomposition of fallen Iogs in nature is due to their

  1. Anaerobic environment around them

  2. Low cellulose content

  3. Low moisture content

  4. Poor nitrogen content
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Photosynthetically fixed carbon is eventually degraded by micro-organisms and two major forms of carbon known as methane and carbon dioxide. The micro-organisms breakdown the complex compounds of dead protoplasm of producers compounds of dead protoplasm of producers and consumers absorb some of the decomposition products and release simple substances. The slow rate of decomposition of fallen logs in nature is because of low moisture content.

Therefore, the correct answer is option C.

Multiple choice zoology ecosystems decomposition in ecosystem ecosystem productivity and decomposition producers, consumers and decomposers

A pollution free stream within a few miles downstream of a point at which a small amount of sewage is being dumped into it. This is the result of

  1. Succession

  2. Eutrophication

  3. Evaporation

  4. Photosynthesis

  5. Decomposition
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation
Presence of decomposers (bacteria) in sewage leads to decomposition of complex organic compounds of sewage into simpler substances. These simpler substances are then consumsed by the decomposers as source of organic compounds. Hence, decomposition of organic compounds and utilization of simper substances by decomposers might have led to formation of pollution free stream out of a sewage dump. 
The process of change in ecological community of an area over time which in turn results in formation of climax community is termed as succession; it does not remove pollutants from the habitat.  
Eutrophication means increased pollutant due to algal blooms as supported by presence of excess organic compounds in water. 
Complex organic substances can not be evaporated. 
Photosynthesis is carried out by autotrophs while sewage is mostly occupied by decomposers. 
Therefore, the correct answer is option E.
Multiple choice commercial studies striving for a better environment soil and its conservations soil pollution-control protecting our environment

The pH of water sample collected from a river was found to be acidic in the range of 3.5 to 4.5, on the banks of the river were several factories that were discharging effluents into the river. The effluents of which one of the following factories is the most likely cause for lowering the pH of river water?

  1. Soap and detergent factory

  2. Lead battery manufacturing factory

  3. Plastic cup manufacturing factory

  4. Alcohol distillery
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Lead battery manufacturing factory have acid electrolyte, so it will cause for lowering tin pH of river water.

Multiple choice biology wastewater story personal and public cleanliness who will do this? basics of water pollution

Biological control during sewage treatment is observed in 

  1. Aerating tanks

  2. Settling tanks

  3. Anaerobic sludge digesters

  4. Primary treatment
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

During secondary treatment, the sewage water is aerated and added with microorganisms like the bacteria and protozoa, these microorganisms degrade organic wastes in presence of oxygen
Multiple choice biology soil : our life soil properties soil - properties basics of soil pollution

Prolonged liberal irrigation of agricultural fields is likely to create a problem of

  1. Acidity

  2. Alkalinity

  3. Salinity

  4. Metal toxicity
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
  • Irrigation is the application of controlled amounts of water to plants at needed intervals. 
  • Prolonged liberal irrigation of agricultural fields is likely to create a problem of salinity, loss of nutrients from the soil. as more amount of water enters through the xylem vessels of the plants the soil becomes waterlogged, vegetations and crop die due to insufficient supply of oxygen.
  • Hence Prolonged liberal irrigation of agricultural fields is likely to create a problem of salinity.
  • So, the correct answer is 'Salinity'.
Multiple choice zoology meaning of life energy flow and loss energy flow in a food chain energy flows

A freshwater organism cannot survive in a water body that has grater ......... that its original habit. 

  1. Oxygen content

  2. Depth

  3. Salt concentration

  4. Water clarity
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

For aquatic organisms the quality (chemical composition, PH) of water is very important. The salt concentration (measured as salinity in parts per thousand), is less than 5 parts per thousand in inland waters, 30-35 parts per thousand in the sea and more than 100 parts per thousand in some hyper saline lagoons. Many fresh water animals cannot live for long in sea water and vice versa because of the osmotic problems they would face. 

So, the correct answer is 'Salt concentration'.

Multiple choice zoology environmental science personal and public cleanliness who will do this? basics of water pollution

If large quantities of domestic sewage is continuously emptied into a small stream, it leads to

  1. depletion of oxygen content in stream water

  2. depletion of nutrients in the stream water

  3. enrichment of oxygen content in stream water

  4. increase in the total amount of life in the stream water.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

If large quantities of domestic sewage are continuously emptied into a small stream, it leads to depletion of oxygen content in stream water as microbes that develop to degrade the organic matter shall consume the oxygen and reduces its amount.

So the correct option is 'depletion of oxygen content in stream water'

Multiple choice botany the living world archaebacteria the three domains of life classification of microbes

Organisms called methanogens are most abundant in

  1. Polluted stream

  2. Cattle yard

  3. Sulphur rock

  4. Hot spring
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Methanogen belongs to Archaebacteria group. They are capable of producing methane gas or marshy gas or biogas. They produces methane gas in marshy areas. They are most abundant in marshy areas and cattle yard where cow sheds are present. The methange gas produces a peculiar odour in these areas.

Thus, the correct answer is 'Cattle yard.'

Multiple choice zoology soil pollution industrial chemicals and their harmful effects toxic wastes and their effects soil pollution-causes

Bottom-feeding fish from the Great Lakes often contain

  1. Lead

  2. Dioxin

  3. Urethane

  4. Polychlorinated biphenyls

  5. B and D
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Polychlorinated biphenyls are a group of man-made chemicals useful in a variety of industrial processes, including the insulation and cooling of electrical equipment. But PCB pollution continues long after its source is cut off. PCBs are still found in the Great Lakes through a process called atmospheric deposition. Pollutants like dioxins and PCBs enter from the air into the water through rain and snow, falling particles, and absorption of the gas form of the pollutants into the water.  Dioxins are chemically similar to PCBs. Lake and river sediments are especially good at holding onto PCBs, so bottom-dwelling fish tend to have higher levels.

Therefore, the correct answer is option E.