Environmental Studies · General Awareness

Water Quality and Pollution

1,263 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 biology micro - organism useful actions of algae introduction to algae algae

Algae have great economic importance to man because

  1. They can be grown in tanks.

  2. They help to restore the fertility of the soil.

  3. Of their high protein content, some algae may be used as future food.

  4. Both B and C.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Algae have great economic importance to man as it is a rich source of protein and some algae may be used as future food apart from this, it is also true that algae enriches the soil and can be a good source to make the soil fertile. Algae are being commercially used by man in many ways. Red algae is used to produce edible gelatin. Thus, the correct answer is option D.

Multiple choice biology micro - organism useful actions of algae introduction to algae algae

Algae are important to study because

  1. They are good organisms to experiment with.

  2. They can be grown in large tank cultures.

  3. They may form important constituents of human food in future.

  4. They produce oxygen and organic acids.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In addition to their ecological roles as oxygen producers and as the food base for almost all aquatic life, algae are economically important as a source of crude oil and as sources of food and a number of pharmaceutical and industrial products for humans. The taxonomy of algae is contentious and subject to rapid change as new molecular information is discovered. The study of algae is called phycology, and a person who studies algae is a phycologist.

Multiple choice biology micro - organism useful actions of algae introduction to algae algae

Algae are useful because they

  1. Purify the atmosphere

  2. Are large in number

  3. Are used in fermentation

  4. Are used to study respiration
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Algae is a collective term for all those chlorophyll bearing organisms which are thalloid. So, during photosynthesis by taking in ${CO _2}$ and giving out ${O _2}$ they purify the atmosphere

Multiple choice biology micro - organism useful actions of algae introduction to algae algae

Which of the following statement supports the fact that studying about algae is important?

  1. They are good experimental materials

  2. They may become important constituent of future food for human beings

  3. They can be easily grown in water tanks

  4. They renew oxygen of atmosphere and water
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Algae are primary producers that can be cultivated as a sustainable food source, which is a significant area of research for future human nutrition.

Multiple choice indicators of pollution biodiversity: conservation human influences on the environment option c: ecology and conservation biology

Some organisms are sensitive to different levels of air pollution and are used as pollution-indicators. Suggest which among the following fits into the category

  1. Fungi

  2. Fresh water algae

  3. Bacteria

  4. Lichens
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Lichens are used as the indicators of air pollution. These structures grow on tree bark and rocks. Air pollutants which are in the gaseous forms get dissolved in the rainwater, especially SO$ _2$ (sulphur dioxide) can damage lichens, and check them from growing. In places where lichens are not growing, it indicates that the air is heavily polluted with sulphur dioxide and other pollutants. 

Thus, the correct answer is option D. 

Multiple choice indicators of pollution biodiversity: conservation human influences on the environment option c: ecology and conservation biology

Common indicator organism of water pollution is

  1. <p>Escherichia coli</p>

  2. <p>Cholera vibrio</p>

  3. <p>Salmonella typhi</p>

  4. <p>Entamoeba histolytic</p>
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Coliform bacteria are found in human faeces. Presence of such bacteria (E. coli is a member of the faecal coliform group) in surface water is a common indicator of faecal contamination. Sanitation program test detects the water for clearing contamination of faeces. Cholera vibrio, Salmonella typhi, Entamoeba histolytica are the pathogens found in the stagnant water or when the medical waste contaminates the water body. 

Hence, the correct answer is 'Escherichia coli'.

Multiple choice indicators of pollution biodiversity: conservation human influences on the environment option c: ecology and conservation biology

Use of lichens in case of pollution is

  1. Treatment of pollutant water

  2. Bioindicators of pollution

  3. Promote pollution

  4. Lichens have no relation with pollution
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Lichen represents the symbiotic association between the algae and fungi. These absorb their mineral nutrients from the atmospheric moisture rather than the soil. So, when the air is contaminated with the sulphur oxides, they show extreme sensitivity to the toxic gas. Their existence is threatened by the oxides of sulphur in the air. The disappearance of the lichen, when exposed to the sulphur oxide, is used as bioindicator of the sulphur pollution in the air. 

So, the correct answer is 'Bioindicators of pollution'

Multiple choice indicators of pollution biodiversity: conservation human influences on the environment option c: ecology and conservation biology

An indicator species of polluted waters is _________

  1. Tubifex

  2. Phytoplankton

  3. Zooplankton

  4. Prawn
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
A. Tubifex, also known as sludge worm or sewage worm, can survive in a eutrophic lake. Hence, it is considered to be a pollution indicator.
B. Phytoplankton are free floating autotrophic and microscopic marine algae.,
C. Zooplankton are the microscopic and heterotrophic organisms that drift in the oceans.
D. Prawn is a crustacean which is used as a source of food.
So, the correct answer is 'Tubifex'.
Multiple choice indicators of pollution biodiversity: conservation human influences on the environment option c: ecology and conservation biology

Which one of the following is not a bioindicator of water pollution?

  1. Sludge-worms

  2. Blood-worms

  3. Stone flies

  4. Sewage fungus
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Any organism which indicates the level of pollution in water is called as bioindicator.
Sludge worms, blood-worms, and sewage fungus are indicators of water pollution. As sludge-worms and blood-worms can survive in water with less oxygen and indicates the presence of organic matter in the water body like sewage fungus.
Stoneflies are found worldwide in running water and cannot survive in polluted water so, their presence indicates the good quality of water.
Multiple choice indicators of pollution biodiversity: conservation human influences on the environment option c: ecology and conservation biology

Polluted waters do not contain

  1. Stone fly larvae

  2. Sewage fungus

  3. <p>Water Hyacinth</p>

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

Insecta plecoptera (stonefly) is a sensitive insect that produces larvae in the water while the adults live on the land. The stonefly larvae are the indicators to the water pollution caused by the increase in the biological oxygen demand and the rise in temperature. Whenever there is an increase in the organic mass, the dissolved oxygen will decrease and the high rate of respiration of the algal bloom would also increase the temperature. Both these conditions are intolerable by the stonefly larvae and they die quickly. They need a high concentration of dissolved oxygen and normal temperature to survive.

Hence, the correct answer is 'Stone Fly Larvae'.

Multiple choice indicators of pollution biodiversity: conservation human influences on the environment option c: ecology and conservation biology

Which is not a bioindicator of water pollution?

  1. Blood worms

  2. Stone flies

  3. Sewage fungus

  4. Sludge worms
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Stoneflies are the aquatic insects that also live on land as adults. These lay their eggs in water and the larvae hatch in the water itself. These larvae are highly sensitive to water pollution as they need a high concentration of dissolved oxygen to respire. They also show sensitivity to the temperature and as the temperature rises, they begin to die. So, when the water is polluted and has low dissolved oxygen and high temperature due to decomposition, the stoneflies will not be seen. Similarly, overgrowth of sewage fungi and sludge worms in the water body indicates a high concentration of organic pollution. Bloodworms are the endoparasite in the human body. 

Hence, the correct answer is 'Bloodworms'.

Multiple choice indicators of pollution biodiversity: conservation human influences on the environment option c: ecology and conservation biology

High amount of Escherichia coli in water is an indicator of

  1. Hardness of water

  2. Industrial pollution

  3. Sewage pollution

  4. Presence of chlorine in water
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Escherechia coli is present in the intestines and is released with the faecal matter. Their presence in the water is indicative of the sewage mixup in the water source.

A. Hardness of water is indicated by the mineral ions concentration.

B. Industrial pollution is indicated by the presence of heavy metals, toxins etc.

C. Escherechia coli presence indicates sewage pollution in water.

D. Chlorine is added for the treatment or purification of water.

Hence, the correct answer is 'Sewage Pollution'.

Multiple choice evs rain: where does it come from sources of water and water cycle availability and forms of water the water cycle

Which of the following is the most important factor in balancing the amount of freshwater on earth?

  1. Water cycle

  2. Greenhouse effect

  3. Waste water treatment plant

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

Water cycle is a continuous cycle in which water changes from water vapour in the atmosphere, through liquid water through condensation and precipitation and then back to water vapour through evaporation, transpiration and respiration. 

Among the given options, $A$ is the correct one. 

Multiple choice commercial applications sources of water conservation of natural and energy resources energy conservation and sources importance of the conservation of natural resources reduce, recycle, reuse

If water pollution continues at its present rate, it will eventually

  1. Prevent precipitation

  2. Stop the water cycle

  3. Make oxygen molecules unavailable to aquatic life

  4. Make nitrates unavailable to aquatic life
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Water pollution is the condition in which there is an increase in the concentration of the undesirable compounds in the water resources. The pollutants are the organic compounds. The microbes use up the oxygen which is present in the water bodies for the degradation of the organic matter in the pollutants. This lowers the amount of oxygen which is available for the aquatic plants and animals.

Thus, the correct answer is option C. 

Multiple choice zoology environmental pollution primary air pollutants air pollution - types and sources not for breathing not for drinking

In pollution, the term 'synergism' is used for

  1. Biomagnification of nondegradable pollutants

  2. Dangerous effect when two pollutants are present together

  3. Decreasing effect to a degradable pollutant

  4. Formation of more potent secondary pollutant from primary pollutants
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Synergism means the process of acting together. In pollution, the synergism is seen when the primary pollutants are less harmful but they combine to form a more potent secondary pollutant. For example, the presence of ozone in the troposphere is undesired and this ozone has come due to the combination of hydrocarbons and nitrogen oxides (both are primary pollutants).

Hence, the correct answer is 'Formation of more potent secondary pollutant from primary pollutants'