Tag: environmental pollution

Questions Related to environmental pollution

Match the columns.

Column-I Column-II
a Nitrous oxide $1$ Secondary pollutant from car exhausts
b Chlorofluorocarbons $2$ Combustion of fossil fuels
c Methane $3$ Denitrification
d Ozone $4$ Refrigerators aerosols, sprays
e Carbon dioxide $5$ Cattle; rice fields, toilets
  1. a-$3$, b-$4$, c-$5$, d-$1$, e-$2$

  2. a-$5$, b-$1$, c-$3$, d-$4$, e-$2$

  3. a-$4$, b-$5$, c-$1$, d-$2$, e-$3$

  4. a-$1$, b-$3$, c-$4$, d-$5$, e-$2$

  5. a-$2$, b-$4$, c-$5$, d-$1$, e-$3$


Correct Option: A
Explanation:
   Column-I    Column-II
 Nitrous oxide  3  Denitrification
 b  Chlorofluorocarbons  4  Refrigerators aerosols, sprays
 c  Methane  5  Cattle, Rice fields, toilets
 Ozone  1  Secondary Pollutant from car exhausts
 e  Carbon dioxide  Combustion of fossil fuels

a. Nitrous oxide is formed as a result of denitrification in which the nitrates are converted to oxides of nitrogen and released into the atmosphere.

b. Chlorofluorocarbons are the ozone-depleting gases that are contributed by the refrigerators, aerosols and sprays.
c. Methane is a greenhouse gas. The digestion activity in the rumen of cattle by the methanogenic bacteria, rice fields and the decomposition of faecal matter in the toilets release the methane into the environment.
d. Ozone in the troposphere is the secondary pollutant formed by the photooxidation of the car exhausts pollutants.
e. Carbon dioxide is also a greenhouse gas whose concentration has increased due to excessive combustion of fossil fuels.
Hence, the correct answer is 'a-3, b-4, c-5, d-1, e-2'.

The first rate pollution monitor are

  1. molluscs

  2. butterflies

  3. honey bee

  4. plants


Correct Option: A
Explanation:

Freshwater molluscs--snails and bivalves--have been used frequently as bioindicator organisms. With increasing needs for research on contaminant effects in freshwater ecosystems, this kind of biomonitoring is likely to develop further in the future. Molluscs can be used effectively for studies of both organic and inorganic contaminants; this review focuses on studies involving bioaccumulation and toxicity of metals. Two important advantages of snails and bivalves over most other freshwater organisms for biomonitoring research are their large size and limited mobility.

So the correct answer is molluscs.

What is meant by root zone process?

  1. A control measure to prevent water pollution

  2. A process by which roots of plants are spread on the ground

  3. A control measure to prevent soil pollution

  4. None of these


Correct Option: A

Sedimentation is a

  1. Primary water treatment

  2. Secondary water treatment

  3. Tertiary water treatment

  4. Final process


Correct Option: A

Toxicity of chemical pollutant in water increases, with increase in

  1. Waste

  2. Water

  3. Temperature

  4. Air


Correct Option: C
Water pollution can be decreased by treating industrial wastes to yield safe effluents.
  1. True

  2. False


Correct Option: A
Explanation:
Water pollution can be decreased by treating industrial wastes to yield safe effluents.
  • Recycling, Renovation, Recharge and Reuse (4R concept) of waste water:
The waste water consisting of domestic sewage industrial effluents, thermal and radioactive pollutants receive some sort of treatment before mixing into water bodies. Urban sewage and sludge, etc, may be recycled and reused to generate cheaper fuel, gas and electricity.
  • Cooling methods:
For preventing thermal pollution such methods are used like cooling waste water effluent, evaporation tower, cooling ponds, dry cooling towers, wet cooling towers etc.
  • Using chemical methods:
Several chemical methods have been devised for the treatment of industrial effluents before discharging them in water bodies.

Therefore, the correct answer is option A.

BOD stands for

  1. Biochemical oxygen demand

  2. Chemical oxygen demand

  3. Biological optimum demand

  4. Biological oxygen demand


Correct Option: A
Explanation:

Biochemical oxygen demand (BOD) is the amount of dissolved oxygen required by aerobic biological organisms to break down organic material present in a given water sample at certain temperature over a specific time period. It is used to measure of the amount of organic waste in water.

Therefore, the correct answer is option A.

Water pollution can be controlled by

  1. Treating sewage or factory wastes to remove harmful organisms and compounds

  2. Using biodegradable fertilizers and pesticides

  3. Both A and B

  4. Electrostatic precipitator


Correct Option: C
Explanation:

Water pollution is the increase in the concentration of the undesirable harmful compounds in the water resources. The water pollution can be controlled by many ways. The sewage and the factory wastes which contain the pollutants and high number of microbes can be treated before letting the water discharged into water bodies. Biodegradable form of fertilizers and pesticides can be used for the reduction of the soil and water pollution, and eutrophication. 

Thus, the correct answer is option C. 

Biological treatment of water pollution is done with the help of

  1. Bacteria

  2. Lichens

  3. Fungi

  4. Both A and C


Correct Option: D
Explanation:

Biological treatment of the waste water can be performed with the use of microbes. The bacteria and fungal cells are commonly used in the treatment of the water through activated sludge. Activated sludge refers to floc of microorganisms including bacterial cells and fungal filaments which are used in the process to break down organic matter into carbon dioxide, water, and other inorganic compounds and help in the clearing of the water. 

Thus, the correct answer is option D.  

Which of these methods is/are used to control water pollution?
(i) Preventing the release of factory wastes into nearby streams.
(ii) Educating society about the dangers of water pollution.
(iii) Using biological control in agricultural areas instead of using pesticides.

  1. Only (i) and (ii)

  2. Only (ii) and (iii)

  3. Only (i) and (iii)

  4. (i), (ii) and (iii)


Correct Option: D
Explanation:

The methods that can be used to control water pollution are:
(i) Avoiding the use of chemical substances freely.
(ii) Educating society about the dangers of water pollution.
(iii) Using biological control in agricultural areas instead of using pesticides.