NCERT Exemplar Solutions Class 10 Science Management of Natural Resources

Multiple Choice Questions.........................

Question 1:  From the list given below to pick the item that is not a natural resource

(a) Soil

(b) Water

(c) Electricity

(d) Air 

Solution 1: (c) Electricity 

Natural resources include soil, water, and air, while electricity is created by humans through the transformation of various sources of energy.

Question 2:  The most rapidly dwindling natural resource in the world is

(a) water

(b) forests

(c) wind

(d) sunlight 

Solution 2: (b) forests

The resources of water, wind, and sunlight are all non-renewable. Forests are being depleted as a result of human activities.

Question 3:  The most appropriate definition of a natural resource is that it is a substance/commodity that is

(a) present only on land

(b) a gift of nature which is very useful to mankind

(c) a man-made substance placed in nature

(d) available only in the forest 

Solution 3:  (b) a gift of nature which is very useful to mankind 

Option a) and d) are incorrect since natural resources are found all over the world. Option d) is incorrect since natural resources are not created by humans.

Question 4:  The main cause for abundant coliform bacteria in the river Ganga is

(a) disposal of unburnt corpses into water

(b) discharge of effluents from electroplating industries

(c) washing of clothes

(d) immersion of ashes 

Solution 4: (a) disposal of unburnt corpses into water

The majority of coliforms are found in human excreta. As a result, unburned bodies are a source of coliform, which pollutes the water of the Ganga river.  

Question 5:  The pH of water sample collected from a river was found to be acidic in the range of 3.5 – 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?

(a) Soap and detergent factory

(b) Lead battery manufacturing factory

(c) Plastic cup manufacturing factory

(d) Alcohol distillery 

Solution 5: (d) Alcohol distillery 

Lactic acid and alcohol are produced during fermentation. Ethanoic acid is formed when alcohol oxidises. The p^H of river water would be lowered as a result of this.

Question 6: The p^H range most conducive for life of freshwater plants and animals is

(a) 6.5 – 7.5

(b) 2.0 – 3.5

(c) 3.5 – 5.0

(d) 9.0 – 10.5 

Solution 6: (a) 6.5 – 7.5 

Freshwater plants and animals prefer a pH of around 7. Freshwater plants and animals prefer a p^H of around 7. As a result, the answer is (a) 6.5–7.5.

Question 7:  The three R’s that will help us to conserve natural resources for long term use are

(a) recycle, regenerate, reuse

(b) reduce, regenerate, reuse

(c) reduce, reuse, redistribute

(d) reduce, recycle, reuse 

Solution 7:  (d) reduce, recycle, reuse 

Three R’s that will help us to conserve natural resources for long term use are reduce, recycle, reuse.

Question 8:  Given below are a few statements related to biodiversity. Pick those that correctly describes the concept of biodiversity

                                 i.            Biodiversity refers to the different species of flora and fauna present in an area

                               ii.            Biodiversity refers to only the flora of a given area

                              iii.            Biodiversity is greater in a forest

                             iv.            Biodiversity refers to the total number of individuals of a particular species living in an area

(a) (i) and (ii)

(b) (ii) and (iv)

(c) (i) and (iii)

(d) (ii) and (iii) 

Solution 8: (c) (i) and (iii) 

Option ii) and iv) are incorrect claims since biodiversity encompasses both flora and fauna, and it does not refer to a single species.

Question 9:  Among the statements given below to select the ones that correctly describe the concept of sustainable development

(i) Planned growth with minimum damage to the environment

(ii) Growth irrespective of the extent of damage caused to the environment

(iii) Stopping all developmental work to conserve the environment

(iv) Growth that is acceptable to all the stakeholders

(a) (i) and (iv)

(b) (ii) and (iii)

(c) (ii) and (iv)

(d) (iii) only 

Solution 9: (a) (i) and (iv)

Environmental protection should not be sacrificed in the name of progress. Option ii) and iii) are both false claims since human development is equally significant.

Question 10:  In our country, vast tracts of forests are cleared and a single species of plant is cultivated. This practice promotes

(a) biodiversity in the area

(b) monoculture in the area

(c) growth of natural forest

(d) preserves the natural ecosystem in the area 

Solution 10:  (b) monoculture in the area  

In our country, large swaths of forest are cleared and a single plant species is grown. Monoculture is promoted in the region as a result of this activity.

Question 11: A successful forest conservation strategy should involve

(a) protection of animals at the highest trophic level

(b) protection of only consumers

(c) protection of only herbivores

(d) comprehensive programme to protect all the physical and biological components 

Solution 11:  (d) comprehensive programme to protect all the physical and biological components 

Option d) is the correct response since biotic and abiotic population balance is critical for forest conservation.

Question 12:  The important message conveyed by the ‘Chipko Movement’ is

(a) to involve the community in forest conservation efforts

(b) to ignore the community in forest conservation efforts

(c) to cut down forest trees for developmental activities

(d) government agencies have the unquestionable right to order the destruction of trees in forests 

Solution 12: (a) to involve the community in forest conservation efforts

The ‘Chipko Movement' emphasises the importance of involving the group in forest conservation efforts.

Question 13:  In our country, there are attempts to increase the height of several existing dams like Tehri and Almati, dams across Narmada. Choose the correct statements among the following that are a consequence of raising the height of dams

(i) Terrestrial flora and fauna of the area is destroyed completely

(ii) Dislocation of people and domestic animals living in the area

(iii) Valuable agricultural land may be permanently lost

(iv) It will generate permanent employment for people

(a) (i) and (ii)

(b) (i), (ii) and (iii)

(c) (ii) and (iv)

(d) (i), (iii) and (iv) 

Solution 13:  (d) (i), (iii) and (iv)

Question 14:  Expand the abbreviation GAP

(a) Governmental Agency for Pollution Control

(b) Gross Assimilation by Photosynthesis

(c) Ganga Action Plan

(d) Governmental Agency for Animal Protection 

Solution 14: (c) Ganga Action Plan

Full form of the abbreviation GAP is Ganga Action Plan.

Question 15:  Select the incorrect statement

(a) Economic development is linked to environmental conservation

(b) Sustainable development encourages development for current generation and conservation of resources for future generations

(c) Sustainable development does not consider the viewpoints of stakeholders

(d) Sustainable development is a long-planned and persistent development 

Solution 15:  (c) Sustainable development does not consider the viewpoints of stakeholders 

Since the participation of all stakeholders is critical to the long-term success of any initiative, choice c) is incorrect.

Question 16:  Which of the following is not a natural resource?

(a) Mango tree

(b) Snake

(c) Wind

(d) Wooden house 

Solution 16: (d) Wooden house

The mango tree, the snake, and the wind are all natural resources, while the wooden house is artificial.

Question 17:  Select the wrong statement

(a) Forests provide a variety of products

(b) Forests have greater plant diversity

(c) Forests do not conserve soil

(d) Forests conserve water 

Solution 17:  (c) Forests do not conserve soil 

Forests help to preserve soil and fertility by preventing soil erosion and adding fertility to the soil by adding humus.

Question 18: Arabari forests of Bengal is dominated by

(a) Teak

(b) Sal

(c) Bamboo

(d) Mangroove 

Solution 18:  (b) Sal 

Arabari forests of Bengal is dominated by Sal.

Question 19:  Groundwater will not be depleted due to

(a) afforestation

(b) thermal power plants

(c) loss of forest, and decreased rainfall

(d) cropping of high water demanding crops 

Solution 19:  (b) thermal power plants 

Groundwater depletion has little to do with thermal power plants, but it is linked to afforestation, which causes seepage and water loss, as well as a reduction in rainfall.

Question 20:  Opposition to the construction of large dams is due to

(a) social reasons

(b) economic reasons

(c) environmental reasons

(d) all the above 

Solution 20:  (d) all the above 

An environmental reason is the destruction of an ecosystem near the dam. People relocating is a social cause. Economic factors have an effect on agricultural land and jobs.

Question 21:  Khadins, Bundhis, Ahars and Kattas are ancient structures that are examples for

(a) grain storage

(b) wood storage

(c) water harvesting

(d) soil conservation  

Solution 21:  (c) water harvesting 

Khadins, Bundhis, Ahars, and Kattas are examples of ancient water harvesting systems.

Question 22:  Pick the right combination of terms which has no fossil fuel.

(a) Wind, ocean and coal

(b) Kerosene, wind and tide

(c) Wind, wood, sun

(d) Petroleum, wood, sun 

Solution 22:  (c) Wind, wood, sun 

Option a) contains gasoline, option b) contains kerosene, and option d) contains petroleum, all of which are fossil fuels, so the correct answer is (c).

Question 23:  Select the eco-friendly activity among the following

(a) Using a car for transportation

(b) Using polybags for shopping

(c) Using dyes for colouring clothes

(d) Using windmills to generate power for irrigation 

Solution 23:  (d) Using windmills to generate power for irrigation 

Using a vehicle for transportation, as well as polybags and dyes for clothing colouring, has a negative impact on the atmosphere, making them non-ecofriendly.

Question 24:  It is important to make small check dams across the flooded gullies because they

(i) hold water for irrigation

(ii) hold water and prevent soil erosion

(iii) recharge groundwater

(iv) hold water permanently

(a) (i) and (iv)

(b) (ii) and (iii)

(c) (iii) and (iv)

(d) (ii) and (iv) 

Solution 24:  (b) (ii) and (iii) 

Check dams help to keep soil from eroding. Check dams aid in the increase of groundwater levels by retaining water.

Short Answer Questions.....................

Question 25:  Prepare a list of five items that you use daily in the school. Identify from the list such items that can be recycled. 

Solution 25:  Steel lunch box, steel spoon, paper, rexin pocket, blade, pen, plastic box, scale, eraser, compass and dividers (metallic), scale, eraser, compass and dividers (metallic).

It is possible to recycle paper, blades, plastic boxes, erasers, compass, steel lunch boxes, and steel spoons.

Question 26:  List two advantages associated with water harvesting at the community level. 

Solution 26:  The following are some of the benefits of group water harvesting:

• Groundwater levels rise as a result of water harvesting.
• Water harvesting retains water on the top layer of the soil, reducing water loss due to evaporation.

Question 27:  In a village in Karnataka, people started cultivating crops all around a lake which was always filled with water. They added fertilisers to their field in order to enhance the yield. Soon they discovered that the waterbody was completely covered with green floating plants and fishes started dying in large numbers.

Analyse the situation and give reasons for excessive growth of plants and death of fish in the lake. 

Solution 27:  Fertilizers used in agriculture wash into the lakes during rainstorms. Fertilizers include phosphates and nitrates, which have been enriched in water bodies. These chemicals encourage the growth of aquatic plants to the point that the water's surface is fully saturated with them.

Fish died as a result of a lack of light in the water body, as well as a lack of dissolved oxygen and nutrients.

Question 28:  What measures would you take to conserve electricity in your house? 

Solution 28:   The following are some ways to save energy in your home:

• When the room/house is empty, turn off the fan and light.
• LED bulbs can be used to replace all incandescent bulbs.
• Use of air conditioners and coolers should be reduced.
• Leaving windows open allows light to reach the home, reducing the amount of light used during the day.

Question 29:  Although coal and petroleum are produced by degradation of biomass, yet we need to conserve them. Why? 

Solution 29:   Since coal and petroleum take millions of years to shape, we must preserve them. Petroleum consumption is outpacing production, and reserves may be exhausted. As a result, it is important to eat them.

Question 30:  Suggest a few measures for controlling carbon dioxide levels in the atmosphere. 

Solution 30:   The following are a few steps for reducing carbon dioxide levels in the atmosphere:

• Take public transportation to minimise automobile emissions.
• Rather than burning waste, manure should be made from it.
• Planting more trees reduces the amount of carbon dioxide in the atmosphere.
• CNG or other environmentally friendly fuels should be used.

Question 31: 

 (a) Locate and name the water reservoirs in the figures below.

(b) Which has an advantage over the other and why?

Solution 31:

(a) A pond ecosystem is depicted in the first figure, while an underwater waterbody is depicted in the second.

(b) For the following factors, a groundwater body has more benefits than a pond ecosystem:

• It is impossible for water to evaporate.
• There will be no insect breeding.
• Animal and human waste can contaminate the water.
• Water would not be able to spread out to replenish wells. Moisture is distributed over a large region.

Long Answer Questions...................................

Question 32:  In the context of conservation of natural resources, explain the terms reduce, recycle and reuse. From among the materials that we use in daily life, identify two materials for each category. 

Solution 32:

Reduce:

Reduction of usage of material or service, for example energy and water.

Recycle:

Recycle refers to returning a used item to the producer so that the content can be used to create another by-product. E.g., paper, plastic utensils, metal objects.

Reuse:

Reuse is the process of reusing a material rather than discarding it. For example, used envelopes, plastic carry bags, and jam bottles.

Question 33:  Prepare a list of five activities that you perform daily in which natural resources can be conserved or energy utilisation can be minimised. 

Solution 33:  List of activities that we perform daily in which natural resources can be conserved or energy utilisation can be minimised:

1. Only wash vehicles when they are dirty.
2. When watering plants, avoid using a hosepipe.
3. Use CFL bulbs/tubes instead of traditional bulbs/tubes.
4. Before going to bed, turn off all the faucets.
5. Only use the fan and light when necessary.
6. Only use solar water heating systems when necessary.
7. Water from the water bottle that hasn't been used can be used to water plants.

Question 34:  Is water conservation necessary? Give reasons. 

Solution 34:  All terrestrial forms of life need water to survive. Water is needed for all life processes, so life is impossible without it.

Water covers 3/4^th of the globe, but the majority of it is in the form of water. As a result, we are unable to use the water for our survival. For our survival, we need safe, clean water. Freshwater makes up less than 1% of the overall water on the planet. As a result, the amount of water available is extremely limited.

When the world's population grows, so does our need for water. As a result, water is overexploited, and people in a few areas face water shortages. As a result, water conservation is needed to save lives.

Question 35:  Suggest a few useful ways of utilising wastewater. 

Solution 35:   The following are some examples of successful wastewater reuse:

• Wastewater can be used for irrigation.
• Wastewater can be used to recharge groundwater.
• Certain contaminants in sewage water can be used as fertiliser for a variety of crops.
• Treated urban water can be used for car washing and garden watering. 

Question 36:  What is the importance of the forest as a resource? 

Solution 36:  The following are some of the reasons why the forest is valuable as a resource:

• The water cycle is controlled by forests.
• Forests increase the soil's ability to retain water.
• Forests include goods such as fruits, resins, gums, essential oils, bidi-wrapper, and other useful items.
• Forests provide wildlife with habitat, food, and defence.
• Forests include all vital resources such as fuel wood, timber pulp and paper, and so on.
• Forests aid in the balance of CO₂ and O₂ levels in the atmosphere.

Question 37:  Why are the Arabari forests of Bengal known to be a good example of conserved forest? 

Solution 37:   The forest department devised a plan that enlisted the help of the villagers in protecting the forest. The villagers were compensated in exchange for their labour, and they also benefited from harvesting operations. On payment of a small fee, they were permitted to collect wood and fodder. The sal forests of Arabari were preserved in this way, thanks to the active and willing involvement of the local people.