Exercise - Question:
Q1. Answer the following questions briefly.
(a) What are the four major domains of the earth ?
Ans. The four realms of the earth are :
(i) Lithosphere, (ii) Hydrosphere, (iii) Atmosphere, (iv) Biosphere.
(b) Name the major continents of the earth.
Ans. The major continents of the earth are :
Asia, Europe, North America, South America, Australia and Antarctica.
(c) Name the two continents that lie entirely in the Southern Hemisphere are :
Ans. 1. Australia, 2. Antarctica
(d) Name the different layers of the atmosphere.
Ans. The different layers of the atmosphere are :
Troposphere, Stratosphere, Mesosphere, Thermosphere and Exosphere.
(e) Why is the earth called the 'blue planet' ?
Ans. More the 71 percent of earth is covered with water. Therefore, from outer space it appears blue. That is why, it is called a blue planet.
(f) Why is Northern Hemisphere called land Hemisphere ?
Ans. The greater part of the land masses lie in the Northern Hemisphere.
(g) Why is the Biosphere Important for the living organisms ? Ans. The Biosphere is the narrow zone of contact between land, water and air. It is in this zone that life that is unique to the planet exists. The growth and survival of the biosphere is made possible by the transfer of energy and matter between elements of the environment.
Q2. Tick the correct answers.
(a) The mountain range that separates Europe from Asia is
(i) the Andes
(ii) the Himalayas
(iii) the Ural
(b) The continent of North America is linked to south America by
(i) Isthmus
(Ii) Strait
(iii) Suez canal
(c) The major continent of atmosphere by per cent is
(i) Nitrogen
(ii) Oxygen
(iii) Carbon dioxide
(d) The domain of the earth consisting of solid rocks is
(i) the Atmosphere
(ii) the Hydrosphere
(iii) the Lithosphere
(e) Which is the largest continent ?
(i) Africa
(ii) Asia
(iii) Australia
Ans. a. (iii), b. (i), c. (i), d. (iii), e. (ii)
Q3. Fill in the blanks.
(a) The deepest point on earth is ......... in the pacific Ocean.
(b) The ......... Ocean is named after a country.
(c) The ........ is the narrow contact zone of land, water and air that supports life.
(d) The continents of Europe and Asia together are known as ........ .
(e) The highest mountain peak on the earth is .........
Ans. (a) Mariana Trench, (b) Indian, (c) Biosphere, (d) Eurasia, (e) Mt. Everest.