Water: A Precious Resource Class 7 Extra Questions and Answers Science Chapter 16

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In this page, we are providing Water: A Precious Resource Class 7 Extra Questions and Answers Science Chapter 16 pdf download. NCERT Extra Questions for Class 7 Science Chapter 16 Water: A Precious Resource with Answers will help to score more marks in your CBSE Board Exams.

Class 7 Science Chapter 16 Extra Questions and Answers Water: A Precious Resource

Extra Questions for Class 7 Science Chapter 16 Water: A Precious Resource with Answers Solutions

Water: A Precious Resource Class 7 Extra Questions Very Short Answer Type

Question 1.
What message do we get from water day?
Answer:
We celebrate water day to attract the attention of everybody towards the importance of conserving water.

Question 2.
What percentage of earth’s surface is covered with water?
Answer:
71%.

Question 3.
What is the two sources through which groundwater gets recharged?
Answer:
The rainwater and water from other sources such as rivers and ponds are the sources for recharging groundwater.

Question 4.
What will happen to plants if they do not get water for few days?
Answer:
Plants will wilt and ultimately dry-up if they are not watered for a few days.

Question 5.
List the main sources of underground water.
Answer:
Springs, tubewells, handpumps, etc.

Question 6.
What is water management?
Answer:
Minimum wastage of water is called water management.

Question 7.
Name the techniques of watering plants which minimises the wastage of water.
Answer:
Drip irrigation.

Question 8.
Why do certain regions on the earth become desert?
Answer:
Certain regions on the earth became desert because they got very little rain.

Question 9.
What is the minimum amount of water per person per day recommended by United Nations?
Answer:
50 Litres.

Question 10.
State any one way to prevent the wastage of water.
Answer:
There should not be any leakage in the supply lines.

Water: A Precious Resource Class 7 Extra Questions Short Answer Type

Question 1.
Define briefly what is water cycle.
Answer:
The continuous movement of water from the water bodies to the atmosphere and again back to the water bodies is called water cycle.

Question 2.
What do you mean by surface water?
Answer:
The water present on the surface of the earth is called the surface water.

Question 3.
What do you mean by rainwater harvesting?
Answer:
Collecting and conserving the rainwater from the roof tops of the buildings is called rainwater harvesting.

Question 4.
How is water table maintained below the earth?
Answer:
The rainwater and water from other sources seeping into the earth maintains the water table. This is called replenishing the water table.

Question 5.
What is the reason due to which earth appear blue from space?
Answer:
The earth appears blue from space because a major part of the surface of earth is covered with water in seas and oceAnswer:It is this water on the earth which makes it appear blue in colour.

Question 6.
What is drip irrigation?
Answer:
Drip irrigation is a technique of watering the plants by making use of narrow tubings which deliver water drop by drop directly at the base of the plant.

Question 7.
What is freshwater?
Answer:
The water that is fit for human consumption is called freshwater.

Question 8.
List the various reasons of depletion of water table.
Answer:
Following are the various reasons for depletion of water table:

  1. Increase in population
  2. Scanty rainfall
  3. Deforestation
  4. Agricultural activities
  5. Industrialization
  6. Decrease in the effective area of seepage of water.

Question 9.
What are bawris?
Answer:
Bawris are the old age practices of water storage and water recharge. It is a step well in which a person can go down by using set of steps to fetch water.

Water: A Precious Resource Class 7 Extra Questions Long Answer Type

Question 1.
What do you mean by conservation of water? How can we conserve water?
Answer:
The process of conservation of water is the wise and judicious use of water by us. We can conserve water by different ways. Rainwater harvesting minimises the wastage of water in houses and industries, us¬ing conservation techniques like drip irrigation in agriculture, etc., are few methods of conservation of water.

Question 2.
Explain briefly what is rainwater harvesting?
Answer:
Collecting and conserving the rainwater from the roof tops of the buildings is called rainwater harvesting. Water from the roof tops of the houses, industries, etc., is collected. It is used directly or allowed to seep into the soil instead of allowing it to flow down. It helps in raising the water table.

Question 3.
List five advantages of conserving water.
Answer:
Following are the five advantages of conserving water:

  1. Protects drinking water resources.
  2. It solves the problem of water scarcity.
  3. It helps to recharge groundwater.
  4. It saves energy and money.
  5. It save freshwater to run off into sea and ocean.

Question 4.
Explain how increasing population is responsible for the depletion of water table.
Answer:
Increasing population creates demands for construction of houses, shops, offices, roads and pavements. This decreases the open areas like parks and playgrounds. This in turn decreases the seepage of rainwater into the ground.

Moreover a huge amount of water is required for construction work and daily chores, often groundwater is used for this purpose. So on the one hand we are consuming more groundwater and on the other we are allowing lesser water to seep into the ground. This results in depletion of water table. In fact, the water table in some parts of many cities has gone down to alarmingly low levels.

Question 5.
How can you contribute towards water conservation?
Answer:
We can contribute towards water conservation by
(a) checking faucets and pipes for leaks.
(b) turning off taps while brushing
(c) mopping the floor instead of washing.
(d) using water after mopping to water the plants.
(e) using grey water from washing machine to flush the toilets.
(f) watering plants in evening and morning to avoid loss of water due to evaporation.

Water: A Precious Resource Class 7 Extra Questions HOTS

Question 1.
What is the source of water in each of the following?
(a) Wells
(b) Atmosphere
(c) Ground
Answer:
(a) Groundwater
(b) Evaporation (from ponds, lakes, transpiration, etc.)
(c) Rain (through infiltration)

Question 2.
Three-fourths of earth is covered with water, then why we need to conserve water?
Answer:
Seas and oceans occupy a vast per cent of water and is salty. This water is unfit for human consumption. Only a little per cent of water is freshwater. Out of this freshwater major portion is present in the frozen form in glaciers, ice caps and permanent snow. Thus, only a little is present as groundwater and much lesser than that as ponds, lakes, rivers, etc. So for our future we need to conserve water.

Question 3.
How scarcity of water can effect education of children?
Answer:
In water scarce area, children cannot attend school regularly since they spend hours in fetching water. Also, many children are not able to attend the school due to water-borne diseases caused due to absence of safe drinking water.

Question 4.
How scarcity of water can effect health as well as economy of an area?
Answer:
Water scarcity will force people to drink contaminated or polluted water. It may also lead to unhygienic conditions as our daily activities need lot of water to keep us clean. Thus, can lead to many infectious diseases. Neither small businesses or major global industries can function properly without water. Also, unhealthy people cannot work properly or able to attend a business. Thus, water scarcity effects health as well as economy of an area.

Water: A Precious Resource Class 7 Extra Questions Value Based (VBQs)

Question 1.
A bottle packaging company established in Rohan’s village started extracting a large quantities of water from the ground. It affected both the quantity and quality of water. All the wells in their village dried up. Women now had to walk nearly five kilometres to fetch water. All the villagers united to protest against the packaging company and led to its permanent closure.
(a) Why the wells in village dried up?
(b) How the quality of groundwater deteriorates due to over-extraction?
(c) How can groundwater be replenished again?
(d) What value of villagers are shown here?

Answer:
(a) Wells in the village dried up due to over-exploitation of groundwater by the packaged drinking water company.
(b) Excessive pumping in coastal areas cause saltwater to move inland and upward, resulting in saltwater contamination of the water supply.
(c) Groundwater can be replenished again through rainwater harvesting by building bunds, check- dams and other methods which helps in much percolation of water into the ground. By planting more and more trees, i.e., reforestation, groundwater level can be increased.
(d) Villagers are conscious of their rights and duty to mother nature, and united.

Question 2.
Water is one of the most important compound for all living things. There can be no life without it. Empty water pots, long queue of women and children, people jostling to get a bucket of water when a tanker arrives, etc., are common scenes at the onset of summer or in water-scarce area. Still many people who are blessed with this precious gift, water, do not bother to waste it thoughtlessly.
(a) Do you think that handling the most precious gift of nature thoughtlessly is correct?
(b) In your level how would you try to minimise the wastage of water?
(c) Write two slogans for conserving water.

Answer:
(a) No.
(b)

  1. Close the tap while brushing.
  2. Check for leaking taps and water pipes.
  3. Use water from mopping for watering plants
  4. Help in spreading water education and creating awareness amongst the masses.

(c)

  1. Water water everywhere, try to save it if you care’.
  2. ‘Slow the; flow, save H20’.