Water Pollution

Q.

What are the 4 steps of eutrophication?

Q.

What is thermal pollution ?

Q.

How is aquatic life affected by water pollution?

Q. How do excessive fertilizers reach the water bodies and pollute them ?

Q. What is the main cause of eutrophication?

1. Photosynthesis
2. Fertilizers
3. Killing of fish
4. Flooding

Q. What are the effects of water pollution?

Q.

Name any three water pollutants.

Q.

Explain the following : (i) Eutrophication ; (ii) Biomagnification.

Q. Biological Oxygen Demand (BOD) is

1. Directly related to dissolved oxygen (DO)
2. The amount of oxygen required by the anaerobic microorganisms to metabolise all the organic waste present in 1 L of water
3. The amount of oxygen required by the aerobic microorganisms to metabolise all the inorganic waste present in 1 L of water
4. The amount of oxygen required by the aerobic microorganism to metabolise all the organic waste present in 1 L of water

Q. Biological Oxygen Demand (BOD) is the measure of

1. Amount of Oxygen present in the Industrial wastes poured into water bodies
2. The extent to which water is polluted with organic compounds
3. Amount of carbon monoxide inseparably combined with haemoglobin
4. Amount of oxygen needed by green plants during the night

Q.

List main sources of water pollution.

Q.

How does water get polluted? [2 MARKS]

Q.

Which of the following does not cause water pollution?

1. Addition of fertilizers to water body

2. Addition of mercury salts to water body

3. Addition of dissolved oxygen to water body

4. Addition of disease-causing bacteria to water body

Q. The accumulation of more pesticides like DDT in higher trophic levels is termed as___________.

1. Biopollution
2. Bioremediation
3. Biomagnification
4. Biological enhancement

Q.

Define eutrophication. What is ill effect of eutrophication?

Q. What are the challenges faced by hydrophytes in their habitat?

Q.

What causes eutrophication?

Q.

Biochemical oxygen demand (BOD) is the amount of oxygen required (in ppm):

1. For the photochemical breakdown of waste present in 1m3 volume of a water body.

2. By anaerobic bacteria to break-down inorganic waste present in a water body.

3. By bacteria to break-down organic waste in a certain volume of water sample.

4. For sustaining life in a water body.

Q. Describe the usefulness of incineration of wastes, and also mention the precautions required in it. <!--td {border: 1px solid #cccccc;}br {mso-data-placement:same-cell;}--> [Review Questions - Pg No.185 - LAT - 4]

Q.

Eutrophication leads to death of fish due to

1. increased $O_2$ content

2. increased algal content

3. decreased $O_2$ content

4. decreased algal content

Q. What happens in water bodies when the water temperature increases?

1. Aquatic life diversity increases in the water.
2. Aquatic life diversity reduces in the water.
3. Amount of dissolved oxygen decreases.
4. Amount of dissolved oxygen increases.

Q. The addition of harmful materials to water that reduces its quality is called water pollution.

1. True
2. False

Q. In a slum area many people were suffering from malaria . Mention two unhygienic conditions prevailing in that area .

Q.

Is biochemical oxygen demand (BOD) used to measure the amount of organic pollutants in water?

Q. Common cold is an acute disease.

1. True
2. False

Q. Select the correct option.

Assertion: Water pollution tends to cause cholera, typhoid, and jaundice.
Reason: Sewage may contain bacteria, viruses, fungi and parasites.

1. Both A and R are correct and R explains A.
2. Both A and R are correct and R does not explain A.
3. Both A and R are incorrect.
4. A is correct, R is incorrect.

Q. Mention any three ways by which potable water can be contaminated.

Q. Most of the fresh water on Earth surface is found in:

1. oceans
2. glaciers
3. rivers
4. underground

Q.

Select the eco-friendly activity among the following

1. Using car for transportation.

2. Using polybags for shopping.

3. Using dyes for coloring clothes.

4. Using windmills to generate power for irrigation.

Q. Question 3
Do you know of any activity which may be polluting the water source?