Class 7 Social Science - Our Environment (Geography) - Chapter Air NCERT Solutions | (i) Wet clothes take longer time to dry

(i) Which of the following gases protects us from harmful sun vays?
(a) Carbon dioxide (b) Nitrogen (c) Ozone

(ii) The most important layer of the atmosphere is
(a) Troposphere (b) Thermosphere (c) Mesosphere

(iii) Which of the following layers of the atmosphere is free from clouds?
(a) Troposphere (b) Stratosphere (c) Mesosphere

(iv) As we go up the layers of the atmosphere, the pressure
(a) Increases (b) Decreases (c) Remains the same

(v) When precipitation comes down to the earth in the liquid form, it is called
(a) Cloud (b) Rain (c) Snow

(i) What is atmosphere?
(ii) Which two gases make the bulk of the atmosphere?
(iii) Which gas creates green house effect in the atmosphere?
(iv) What is weather?
(v) Name three types of rainfall?
(vi) What is air pressure?

(i) Solve this Crossword puzzle with the help of given clues:

(i) Trade Winds                                     (a) Incoming solar energy
(ii) Loo                                                  (b) Seasonal wind
(iii) Monsoon                                        (c) Horizontal movement of Air
(iv) Wind                                              (d) Layer of ozone gas
                                                            (e) Permanent wind
                                                            (f) Local wind

(i) What is an ecosystem?

(ii) What do you mean by natural environment?

(iii) Which are the major components of the environment?

(iv) Give four examples of human made environment.

(v) What is lithosphere?

(vi) Which are the two major components of biotic environment?

(vii) What is biosphere?

(i) What are the three layers of the earth?
(ii) What is a rock?
(iii) Name three types of rocks.
(iv) How are extrusive and intrusive rocks formed?
(v) What do you mean by a rock cycle?
(vi) What are the uses of rocks?
(vii) What are metamorphic rocks?

(i) Why do the plates move?
(ii) What are exogenic and endogenic forces?
(iii) What is erosion?
(iv) How are flood plains formed?
(v) What are sand dunes?
(vi) How are beaches formed?
(vii) What are ox bow lakes?

(i) What is precipitation?
(ii) What is water cycle?
(iii) What are the factors affecting the height of the waves?
(iv) Which factors affect the movement of ocean water?
(v) What are tides and how are they caused?
(vi) What are ocean currents?

(i) Which are the two factors on which the growth of vegetation mostly depends?
(ii) Which are the three broad categories of natural vegetation?
(iii) Name the two hardwood trees commonly found in tropical evergreen forest.
(iv) In which part of the world are tropical deciduous forest found?
(v) In which climatic conditions are citrus fruits cultivated?
(vi) Mention the uses of coniferous forest.
(vii) In which part of the world is seasonal grassland found?

(i) What are the four means of transport?
(ii) What do you understand by the term ‘settlement’?
(iii) Which are the activities practised by the rural people?
(iv) Mention any two merits of railways.
(v) What do you understand by communication?
(vi) What is mass media?

(i) Name the continent in which the Amazon Basin is located.
(ii) What are the crops grown by the people of the Amazon Basin.
(iii) Name the birds that you are likely to find in the rainforests of the Amazon.
(iv) What are the major cities located on the River Ganga.
(v) Where is the one-horned rhinoceros found?

(a) What are the two types of deserts found in the world?
(b) In which continent is the Sahara desert located?
(c) What are the climatic conditions of the Ladakh desert?
(d) What mainly attracts tourists to Ladakh?
(e) What type of clothes the people of the Sahara desert wear?
(f) Name the trees that grow in Ladakh.

(i) Which is not a natural ecosystem?
(a) Desert (b) Aquarium (c) Forest

(ii) Which is not a component of human environment?
(a) Land (b) Religion (c) Community

(iii) Which is a human made environment?
(a) Mountain (b) Sea (c) Road

(iv) Which is a threat to environment?
(a) Growing plant(b) Growing population (c) Growing crops

(i) The rock which is made up of molten magma is
(a) Igneous (b) Sedimentary (c) Metamorphic

(ii) The innermost layer of the earth is
(a) Crust (b) Core (c) Mantle

(iii) Gold, petroleum and coal are examples of
(a) Rocks (b) Minerals (c) Fossils

(iv) Rocks which contain fossils are
(a) Sedimentary rocks
(b) Metamorphic rocks
(c) Igneous rocks

(v) The thinnest layer of the earth is
(a) Crust (b) Mantle (c) Core

(i) Ocean water is salty.
(ii) The quality of water is deterioting.

(i) Sahara is located in which part of Africa
(a) eastern (b) northern (c) western

(ii) Sahara is what type of desert
(a) cold (b) hot (c) mild

(iii) The Ladakh desert is mainly inhabited by
(a) Christians and Muslims
(b) Buddhists and Muslims
(c) Christians and Buddhists

(iv) Deserts are characterised by
(a) scanty vegetation
(b) heavy precipitation
(c) low evaporation

(v) Hemis in the Ladakh is a famous
(a) temple (b) church (c) monastery

(vi) Egypt is famous for growing
(a) wheat (b) maize (c) cotton

(i) Mosses and Lichens are found in:
(a) Desertic Vegetation
(b) Tropical evergreen forest
(c) Tundra vegetation

(ii) Thorny bushes are found in:
(a) Hot and humid tropical climate
(b) Hot and dry desertic climate
(c) Cold polar climate

(iii) In tropical evergreen forest, one of the common animals is:
(a) Monkey (b) Girraffe (c) Camel

(iv) One important variety of coniferous forest is:
(a) Rosewood (b) Pine (c) Teak
(v) Steppe grassland is found in

(a) S. Africa (b) Australia (c) Central Asia

(i) The rainforests are depleting.
(ii) Paddy is grown in the Ganga-Brahmaputra plains.

(i) Which are the two factors on which the growth of vegetation mostly depends?
(ii) Which are the three broad categories of natural vegetation?
(iii) Name the two hardwood trees commonly found in tropical evergreen forest.
(iv) In which part of the world are tropical deciduous forest found?
(v) In which climatic conditions are citrus fruits cultivated?
(vi) Mention the uses of coniferous forest.
(vii) In which part of the world is seasonal grassland found?

(i) Oasis                                                          (a) Libya
(ii) Bedouins                                                   (b) monastery
(iii) Oil                                                             (c) glacier
(iv) Gangri                                                      (d) depressions with water
(v) Lamayuru                                                 (e) cold desert
                                                                       (f) Sahara 

(i) Which is not a natural ecosystem?
(a) Desert (b) Aquarium (c) Forest

(ii) Which is not a component of human environment?
(a) Land (b) Religion (c) Community

(iii) Which is a human made environment?
(a) Mountain (b) Sea (c) Road

(iv) Which is a threat to environment?
(a) Growing plant(b) Growing population (c) Growing crops

(i) Collect pictures and photographs of forests and grasslands of different parts of world. Write one sentence below each picture.
(ii) Make a collage of rainforest, grassland and coniferous forests.

(i) Glacier                                      (a) Sea shore
(ii) Meanders                                (b) Mushroom rock
(iii) Beach                                     (c) River of ice
(iv) Sand dunes                           (d) Rivers
(v) Waterfall                                 (e) Vibrations of earth
(vi) Earthquake                            (f) Sea cliff
                                                    (g) Hard bed rock
                                                    (h) Deserts

(i) Name the continent in which the Amazon Basin is located.
(ii) What are the crops grown by the people of the Amazon Basin.
(iii) Name the birds that you are likely to find in the rainforests of the Amazon.
(iv) What are the major cities located on the River Ganga.
(v) Where is the one-horned rhinoceros found?