DAV Class 7 SST Solution Chapter 1 Components of Environment
DAV School Books Class 7 SST Solution Chapter 1 Components of Environment all Question Answer. DAV Class 7 1st Chapter Components of Environment full Chapter explanation by expert teacher.
DAV School Books Class 7 SST Solution Chapter 1 Components of Environment:
(A) Tick the correct option.
(1) Which one is not a part of biological environment?
(a) Plants
(b) Water
(c) Animals
(d) Human beings
Ans: (b) Water.
(2) Volcanoes erupt due to –
(a) Internal disturbance of the earth
(b) External disturbance of the earth
(c) Climate change
(d) Man-made changes on the earth
Ans: (a) Internal disturbance of the earth.
(3) Which one brings a sudden change in the environment?
(a) Formation of a river
(b) Rainfall
(c) Growth of a plant
(d) Formation of a mountain
Ans: (b) Rainfall.
(4) Identify by the term that stands for the topmost layer of the earth comprising of loose material-
(a) Minerals
(b) Soil
(c) Sial
(d) Sima
Ans: (c) Sial.
(5) In which year was the wildlife protection Act passed in India?
(a) 1971
(b) 1972
(c) 1973
(d) 1974
Ans: (b) 1972.
(C) Match the following:
(1) Physical environment includes |
(a) Atmosphere |
(2) It is the most dynamic in nature |
(b) Human beings |
(3) A narrow zone supporting life |
(c) Non-living things |
(4) They are capable of modifying environment |
(d) Biosphere |
(5) Rocks rich in silica and magnesium |
(e) Sima |
Ans:
(1) Physical environment includes | (c) Non-living things |
(2) It is the most dynamic in nature | (a) Atmosphere |
(3) A narrow zone supporting life | (d) Biosphere |
(4) They are capable of modifying environment | (b) Human beings |
(5) Rocks rich in silica and magnesium | (e) Sima |
(D) Answer the following questions in brief.
(1) Name the major components of the environment.
Ans: The major components of the environment are –
(1) Natural elements –
(i) Physical components
(ii) Biological components
(2) Man-made elements
(2) What is meant by Sima and Sial?
Ans: Sial- the uper most layer of the lithosphere is called Sial because this layer is mainly composed with silica and alluminium. Sima-below the Sial, the layer is reached with sillicon and magnesium and called Sims.
(3) Mention the distribution of water in the Northern and Southern hemispheres.
Ans: Distribution of water is in the northern hemisphere and southern hemisphere – The earth is often called blue planet or water planet as it’s 71 percent area is covered with water. But the distribution of water is not even in both the hemisphere of the Earth. Such as 43 percent area of northern hemisphere is covered with water where as 51 percent area of southern hemisphere is covered with water.
(4) Give the literal meaning of four spheres of environment.
Ans: The natural environment is broadly divided into four spheres
(i) Lithosphere or literally we can call sphere of rocks.
(ii) Hydrosphere or sphere of water
(iii) Atmosphere means sphere of air
(iv) Biosphere or literally sphere of life
(5) What is the atmosphere composed of?
Ans: Atmosphere is composed of a mixture of gases, extending about 1600 km above the earth surface.
(E) Answer the following questions –
(1) Differentiate between the physical and the biological environment.
Ans: Physical environment – Its a part of natural environment and all the non-living things like land, water and air belong to it.
Biological environment – it is also a part of natural environment and all the living things belong to biological environment.
(2) Why is the earth called the ‘Blue Planet’?
Ans: 71 percent of the earth surface is covered with water including sea, river, pond, lake etc. The earth is called blue planet because maximum area of the earth is covered with water.
(3) Define biosphere. Why is it important for us?
Ans: Biosphere-Biosphere is called a link between all the other three spheres-atmosphere, hydrosphere and Lithosphere because all kind of life exists over here and it’s a called sphere of life.
Biosphere-Biosphere is important for us because it’s full of life. It creates a direct link between lithosphere, atmosphere and hydrosphere. It’s a rich variety of micro organisms, plants and animals.
(4) Explain with the help of an example how physical and biological components of the environment are interdependent.
Ans: Physical and biological environments are interdependent. We can say this because a change can put an effect on the physical and biological environments simultaneously. For example soil is a part of physical environment. The changes occurring inside the soil take millions of the year but because of these changes earthquake, landslides, volcanic eruptions occur. These activities affected the lives of the biological environment.
(5) Explain two ways in which human beings are disturbing the natural environment.
Ans: Human beings are disturbing the natural environment by cutting forests and interfering into the plant and animal. Lives. For their own benefits and comfort they are utilising and destroying plant and animal lives. Continuous cause of pollution artificially or intentionally created by human beings brutally affecting the plant and animal lives.
For more updates, follow our netexplanations home page
Thank you soo much my dought clears .