Topic outline

    • Conservation of Plants and Animals

      Q36. How does deforestation lead to frequent floods?

      Ans. Deforestation leads to a decrease in the water holding capacity of the soil. The movement of water from the soil surface into the ground (infiltration rate) is reduced. A lot of rain water from deforested soil rushes into the river quickly, causing floods.

       

      Q37. What is desertification?
      Or
      How can deforestation lead to desertification?
      Or
      How does deforestation lead to reduced soil fertility?

      Ans. Trees roots hold the soil in position and prevent soil erosion. Fewer trees result in more soil erosion. Removal of the top layer of the soil exposes the lower, hard and rocky layers. This soil has less humus and is less fertile. Gradually the fertile land gets converted into deserts. It is called desertification.



      Q38. What is the reason for global warming?
      Or
      What Causes Global Warming?

      Ans. Plants need carbon dioxide for photosynthesis. Fewer trees would mean that less carbon dioxide will be used up resulting in its increased amount in the atmosphere. Carbon dioxide traps the heat rays reflected by the earth. Trapping of heat rays by carbon dioxide increases the temperature of earth’s atmosphere. This will lead to global warming.

       

      Q39. Explain how by killing small animals, we are actually harming ourselves.

      Ans. At times, we kill snakes, frogs, lizards, bats and owls ruthlessly without realising their importance in the ecosystem. By killing them we are harming ourselves. They might be small in size but their role in the ecosystem cannot be ignored. They form part of food chains and food webs which are essential for maintaining a balance in nature.

       

      Q40. Explain how deforestation leads to reduced rainfall.

      Ans. Plants need carbon dioxide for photosynthesis. Fewer trees would mean that less carbon dioxide will be used up resulting in its increased amount in the atmosphere. This will lead to global warming as carbon dioxide traps the heat rays reflected by the earth. The increase in temperature on the earth disturbs the water cycle and may reduce rainfall. This could cause droughts.



      Q41. Differentiate between wildlife sanctuary and biosphere reserve.

      Ans. Difference between wildlife sanctuary and biosphere reserve

      Wildlife Sanctuary

      Biosphere Reserve

      1. Areas where animals are

      protected from any disturbance to them and their habitat.

      1. Large areas of protected land for conservation of wildlife, plant and animal resources and traditional life of the tribals living in the area.


      2. Example : Bori and

      Pachmarhi

      2. Example: Pachmarhi Biosphere Reserve

       

      Q42. Differentiate between zoo and wildlife sanctuary.

      Ans. Difference between zoo and wildlife sanctuary

      Zoo

      Wildlife Sanctuary

      1. In a zoo, animals and birds live in artificial settings.

       

      1. In a wildlife sanctuary, animals and birds live in their natural habitat.

      2. Animals are not comfortable living in the artificial environment of zoo.

      2. Animals are comfortable in the natural environment of a wildlife sanctuary.



      Q43. Differentiate between endangered and extinct species.

      Ans. Difference between endangered and extinct species

      Endangered Species

      Extinct Species

      1. Endangered species are those which are facing the danger of extinction.

      1. Extinct Species are those which no longer exist on earth.


      2. Example: desert cat, tiger, snow leopard etc.

      2. Example: dinosaur, dodo, cave lion etc.

       

      Q44. Differentiate between flora and fauna.

      Ans. Difference between flora and fauna

      Flora

      Fauna

      1. Plants that grow naturally in a particular area are called flora of that area.

       

      1. Animals that live naturally in a particular area are called fauna of that area.

      2. Example: sal, teak, mango, jamun, silver ferns, arjun, etc. are examples of the flora of the Pachmarhi Biosphere Reserve.

      2. Example: chinkara, blue-bull, barking deer, cheetal, leopard, wild dog, wolf, etc. are examples of the fauna of the Pachmarhi Biosphere Reserve.



      Q45. Why should we conserve biodiversity?
      Or
      Why should forests and wildlife be conserved?

      Ans. Biodiversity is of great importance in order to maintain stable ecosystems. Each species has a specific role and function in an ecosystem. These roles include capturing and storing energy, providing food resources, providing medicinal resources,  decomposing organic matter, cycling water and nutrients, promoting soils formation, controlling erosion, controlling pests and climate regulation, adding to soil fertility, pollination, plant growth etc. All organisms are interdependent on others for survival; the removal of one species may have a significant effect on others.


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