ANSWER KEY
Unit 1—Our Universe
Chapter 1: The Solar System
Exercises (on page 14)
(A)
1. (a) chromosphere
2. (d) solar prominences
3. (c) tongues or loops of gases extending tens of thousands of
kilometres on the Sun.
4. (c) indicate the presence of strong magnetic fields.
5. (d) during solar eclipse
(B)
1.Asteroids
2.two
3.Ceres
4.Venus
5.Moon
6. Solar Prominences
(C)
1. Big Bang Theory
2. Proxima Centauri
3.Sun
4. Halley's Comet
5.Titan
6.Asteroids
(D)
1.False2. True
3.False4. False
5.True6. False
7.False
(E)1. Mercury is closest to the Sun and so it is able to revolve
around the Sun in just 88 days, which is the shortest period
of revolution.
2. Venus has a thick poisonous atmosphere that conceals its
surface and traps heat.
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Price : `45.00
3. Strong winds blow on the planet and this gives it a striped
look. As the gases in the atmosphere circle the planet, strong
wind blow here and this results in its fast spin. They produce
colourful belts and zones.
4. It does not have an atmosphere and moisture. It also
experiences extremes of temperature.
5. A small amount of methane is present in it.
6. (i) The earth is at a right distance from the Sun.
(ii) It has abundance of water (71%).
(iii) The atmosphere acts as a blanket protecting the Earth
from extremes of temperatures.
(iv) I has oxygen, nitrogen, carbon dioxide, ozone and
hydrogen.
(v) The biosphere provides us with food, shelter, clothing
and minerals.
(F)
1. Life not possible on Jupiter because the gases present in
its atmosphere contain methane and ammonia, apart from
hydrogen and helium.
2. Uranus appears to rotate on its sides, so Uranus has very
strange seasons—summer here is 42 years long.
3. Comets are heavenly bodies revolving around the Sun in
elongated elliptical orbits. They are bodies of ice and dust.
When they approach the Sun, they heat up and release
glowing tails of dust and gas blowing away from the Sun.
4. Planets are classified according to their distance from the
Sun–
(i) Inner Planets/Inferior Planets
(ii) Outer Planets/Superior Planets.
5. Mercury spins on its axis slower than the Earth—once in
every 58.6 days on Earth.
6. On Venus and Uranus the Sun sets in the east, because the
planets Venus and Uranus rotates from east to west.
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7. The Sun is the biggest member of the system and an important
source of heat and light. It is a medium size star, with a
diameter about 1,392,684 km and its mass about 2 × 1030
kilograms, 330,000 times of Earth's. The Sun's gravitational
force is very strong and it holds all the heavenly bodies in
their orbits. Four hydrogen atoms combine to produce one
helium atom and a lot of energy is released. The Sun's energy
is the result of nuclear fusion. Sun also has mountains and
valleys, the Sun has sunspots and storms.
Unit 2—Our Atmosphere
Chapter 2: Weather and Climate
Exercises (on page 26)
(A)
1. (b) water droplets
2. (c) decreases
3. (c) Altitude
4. (b) Earth's rotation
5. (a) atmospheric pressure
6. (b) decreases as you go further from the equator and decreases
with altitude
7. a. True
b. True
c. False
d. False
(B)
1. Weather —The state of the atmosphere of a place over a short
period of time.
2. Oktas—The amount of cloud cover in the sky is expressed
in oktas (eights).
3. Lapse rate—The rate at which the temperature drops with
altitude in the atmosphere is known as lapse rate.
4. Celsius—The Celsius degree is almost twice as large as
the Fahrenheit degree: 1°C = 1.8°F. In the Celsius scale, the
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freezing point of water is 0°C and its boiling point is 100°C.
Today the Celsius scale is largely in use all over the world.
5. Current – The vertical movement of air is called currents.
(C)
1.winds
2.humidity
3.decreases
4. Hot, low
5. high, low
(D)
1. The important elements of weather are temperature,
moisture, wind, sun, cloud cover and atmospheric pressure.
2. Clouds are visible mass of water droplets or frozen ice
crystals suspended in the atmosphere above the surface of
the earth. Cloud cover affects weather conditions. During
the daytime a cloud-covered sky reflects the sunshine and
reduces insolation and also the amount of heat received.
It also prevents radiation from the Earth's surface. Cloudy
days and nights are warmer than cloudless ones. Cloudless
skies indicate fair weather while saturated clouds indicate
rainfall. Thick dark clouds bring heavy rainfall while white
clouds indicate fair weather.
3. The atmospheric pressure, at a given place and at a given
time, is the weight of the overlying atmosphere pressing
down on unit area of that place.
4. When air gets cooled, they condense to form masses of frozen
vapour which we call clouds. When clouds get loaded with
water vapour, they can no longer remain suspended in the
air, and falls on the Earth as tiny droplets, which we call
precipitation. Rain, snow, hailstorm, fog, mist, dew are the
various forms of precipitation.
5. Moving air is called wind. The unequal heating on the surface
of the Earth, causes the winds.
(E)1.23
6
1°
1°
N to 23
S – Torrid Zone
2
2
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2.23
1°
1°
N to 66
S – Temperate Zone
2
2
3.66
°
°
1°
1°
N and 66
S to 90 N and 90 S pole – Frigid Zone
2
2
Unit 2—Our Atmosphere
Chapter 3: Temperature and Rainfall
Exercises (on page 34)
(A)
1. b. Decreases as you go farther from the equator and decreases
with altitude
2. d. Places near the equator receives Sun's rays with a slanting
angle. – True because Sun's rays are almost vertical near the
equator through out the year.
(B)
1. Temperature—The degree of hotness or cloudiness of the
air in the atmosphere is called a temperature.
2. Stevenson Screen—An enclosure to shield meteorological
instruments against precipitation and direct heat radiation
from outside sources, while still allowing air to circulate
freely around them.
3. Range of temperature—Temperature range is the extent of
diurnal or seasonal (annual) temperature variation.
4. Elements of weather—Temperature, humidity, air pressure,
precipitation, sunshine and cloud cover are known as the
elements of weather.
(C)
1. To record the shade temperature of the air. 2. So that evaporation is kept to a minimum.
(D)
1.285 ÷ 12 = 23.75°C
2.May
3.January
4.12°C
5.July
6. 763 cm
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Unit 2—Our Atmosphere
Chapter 4: Atmospheric Pressure and Winds
Exercises (on page 46)
Q. 1(A)
1. a. It is less dense than cold air
2. a. typhoon
3. b. anemometer
4. a. Uneven heating of the Earth causes a change in weather
5. b. Puri
6. ii. Air contracts on heating. – False
iv. Cold air rises – False
7. d. All of the above
(B)
a. iii. other name of cyclone
b. ii. name of cyclone in Japan
c. iv. a dark funnel-shaped cloud
d. i. eye of a cyclone
(C)
1. The weight of the overlying atmosphere pressing down on
a unit area of the place pressure exerted ont he Earth as a
result of its weight.
Any two factors –
i. Temperature
ii. Altitude
iii.Rotation of the earth
iv.Presences of water vapour
2. The unequal heating of the Earth's surface and the differences
in air pressure cause air to move.
3. Local winds
i. Chinook – USA and Canada
ii. Foehn – Alps
iii.Loo – North India
iv. Bora – Hungarian Basin
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v. Mistral – North-west Mediterranean coast of France and
Spain.
4.A cyclone is a huge storm that originates at sea. It is
characterised by a low pressure centre and strong wind
spiraling inward and upward. They develop in the trade
wind belt between latitudes 5°N and 20°S of the equator.
Due to the rotation of the Earth, cyclones rotate in an anticlockwise direction in the Northern Hemisphere, and in a
clockwise direction in the Southern Hemisphere around the
'eye'.
5. Monsoon winds are seasonal. These are caused due to the
differential heating of the land masses and oceans.
6. Anticyclones can become stationary, giving settled weather,
clear skies and calm winds.
(D)
1. Doldrums
2. Aneroid Barometer
3.Millibar
4. High Pressure
5. South Westerly Winds
6. North-East Trade Winds
(E) 1.night
2. Valley breeze
3. Monsoon winds, warm
4. Coriolis force
(F)
1. Air expands on being heated, becomes lighter and rises,
creating an area of low pressure on the land.
2. On a warm summer day along the coast, uneven heating of
land and sea leads to the development of a local wind called
sea breeze.
3. Because of the rotation of the earth.
4. On the mountains, the thickness of air is less and hence
atmospheric pressure is less moisture laden winds.
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5. The South-West monsoon winds originate over the Indian
Ocean. They are loaded with moisture and humidity. As
they reach Indian Peninsular and find any barrier they rain
heavily. They bring heavy rain to the west coast of India.
(G)
1. Land breeze—A periodic local wind blowing from land to
sea at night.
Sea breeze—A periodic local wind blowing from sea to land
during the day.
2. Cyclone—A cyclone is a huge storm that originates at sea. It
is characterised by a low pressure centre and strong winds
spiraling inward and upward. They develop in the trade
wind belt between latitudes 5°N and 20°S of the equator.
Anticyclone—A high pressure system with gentle winds
blowing outwards from the centre.
3. Planetary winds—These winds blow constantly in a
particular direction throughout the year and are known
as planetary or permanent or prevailing winds. The trade
winds, westerlies and polar winds are the main planetary
winds.
Local winds—These are localised over small areas and can
be warm and cold winds.
4. Loo—Loo is a local wind blowing in summers in North India.
Nor'Westers – are also known as Kaal Baisahakhi, a violent
thunderstorm in Bengal, Assam (India).
Unit 2—Our Atmosphere
Chapter 5: Moisture in the Atmosphere
Exercises (on page 57)
(A)
10
1. a. Evaporation is the process through which water changes
into vapour.
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2. a.Air rising in currents from a heated surface
3. d. Dry Bulb Thermometer
4. d.Nimbus
5. b. water droplets
(B)
1. The moisture in the atmosphere help to bring rain.
2. The continuous movement of water from oceans, seas,
rivers and other water bodies to the atmosphere; to the
land as precipitation and back to the oceans is known as the
hydrological cycle or the water cycle.
3.When saturated air is subjected to cooling the capacity to
hold water vapour decreases and the water vapour changes
to liquid or solid. The convectional rainfall occurs every
afternoon.
4. The Sun warms up the Earth and the air above it during the
day. When the air gets heated it expands, becomes lighter,
rises higher into the atmosphere and cools. Thus a convection
current is set up in the atmosphere due to local heating. On
reaching the upper layers the air cools. When dew point
is reached large cumulonimbus clouds are formed. Water
vapour condenses and heavy rain occurs, accompanied by
thunder and lightning. This rainfall does not last long. These
rain showers are called thunder showers. This type of rainfall
is called convectional rain. It is also known as to 4 o'clock
showers.
5. Snow, hail, fog, mist and dew are the forms of precipitation.
(C)
1.Cirrus/Cerro
2.Cyclone
3.Rain
4. Dry and Wet Bulb Thermometer / Hygrometer
5. Convectional rainfall
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(D)
1. Condensation—The change of water vapour to water on
cooling.
Precipitation—The process of condensation leads up to
precipitation.
2. Dew—The temperature at which air gets saturated in the
water vapour that it is carrying.
Frost—In the early morning when temperature falls below
0°C, dew drops deposit on the cool surfaces, plants, benches,
rocks and the ground, freeze into tiny crystals of ice. These
frozen dewdrops are called frost.
3. Relief Rainfall—This type of rainfall occurs when onshore
moisture-laden winds come across a mountain barrier. The
mountains force the wind to rise. As the winds rise up, they
cool. Clouds form and rainfall occurs on the wind wards side
of the mountain or rainward side.
Frontal Rainfall—Warm air being lighter advances and rises
above the cold air, which is heavier and denser. The surface
they meet along is called a front. As they meet along the
front, water vapour condenses and rainfall occurs.
4.
Fog—A warm moist air mass blowing over a cold surface,
usually snow or ice, or over a cold ocean surface can cause
a fog.
Mist is thin fog resulting from condensation of air near the
Earth's surface. When the air cools below the dew point water
vapour condenses near the ground. This mixes with dust in
air and forms mist.
5. Cumulus clouds are fluffy clouds with flat bases. The word
cumulus means 'heap' or "globular". They have a flat base and
cauliflower-like rounded top. Some cumulus clouds are more
than 9–10 km high. They often bring heavy thunderstorms.
Nimbus clouds – Nimbo means rain. These are rain bearing
clouds and are generally found in lower altitudes.
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1.False
2.True
3.True
(E)
4.False
(F)
5.True
1. – Evaporation is faster when the wind blows.
2. – Water vapour in the air has cooled and condensed to form
dewdrops on the grass.
3. – Mahabaleshwar lies on the windward side of the Western
Ghats.
4. – Cumulonimbus clouds are formed, water vapour condenses
and heavy rain occurs, accompanied by thunder and
lightning.
5. –The water vapour changes to liquid or solid. This process
is called condensation.
Unit 3—Our Atmosphere
Chapter 6: Pollution and Its Control
Exercises (on page 65)
(A)
1. d.Ozone in the upper part of atmosphere is harmful to
animals.
2. b. Transparent to heat but traps sunlight.
(B)
1. Agricultural waste / Animal waste.
2. Crop rotation/mulching/contour ploughing.
3. Water hyacinth
4. Polluting gases like carbon monoxide, sulphur dioxide,
nitrogen dioxide, ozone.
(C)
1. low yields
2. dust filters, scrubbers and electrostate
3. air pollution
4. Mechanical process which involves screening, grinding,
flocculation and sedimentation, biological process and
chemical process.
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5.leaching.
6.pollution.
(D)
1. Pollution is contamination of the Earth's environment with
materials that interfere with the natural functioning of ecosystems – living organisms and their physical surroundings.
2. To reduce pollution the main aim should be to reduce the
output of the polluting gases like carbon monoxide, sulphur
dioxide, nitrogen dioxide, ozone, etc.
3. Emissions from vehicles, fossil fuels, smoke in the factories
caused by coal, etc.
4. To control thermal operation, industries should allow the
water to cool properly before releasing it into the river or
pond.
5. Water hyacinth, agricultural waste, animal wastes, urban
run-off, water run-off are some of the reasons which pollute
the water.
Unit 3—Europe
Chapter 7: Europe—The Land
Exercises (on page 74)
(A)
1. Fjords—The narrow deep inlets with steeply rising sides are
fjords. These fjords are responsible for the highly indented
coastline.
2. Land-locked countries—Countries having no coastline and
surrounded by other countries.
3. Balkan states—The countries in the Balkan Peninsula –
Greece, Albania, Macedonia, Romania and Bulgaria.
4. Eurasia—The division between Europe and Asia as two
different continents is a historical and cultural construct, with
no clear physical separation between them. This continuous
land mass it forms is called Eurasia.
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5. Benelux countries—The low countries : Belgium,
Netherlands, Luxemburg of low altitudes.
(B)
1. The Scandinavian countries are also called the Nordic
countries which include Norway, Sweden, Denmark, Finland
and sometimes Iceland.
2. The west-flowing rivers are Guadalquivir, Tagus, Douro,
Ebro, Garonne, Rhone, Po, Loire, Seine, Rhine, Weser, Elbe
Oder, Vistula.
3. The Alpine mountain system includes the Cantabrian
mountains of Northern Spain, the Sierra Nevada in Spain
and France, the Apennines extending southwards in Italy.
On the eastern side there are two branches—che Carpathian
in Slovakia, Poland, Ukraine and Romania and the Balkans.
The Dinaric Alps runs southwards into the Balkan Peninsula
and the Pindus mountain in Greece.
4. The North Western Highlands consists of the highland
systems running from Finland through Norway to Scotland.
These are among the oldest mountain systems of Europe
made up of old and hard rocks. These mountains were
covered by thick sheets of ice during the great Ice Age, which
were responsible for the general lowering in height and the
formation of rounded hills due to ice erosion.
5. Austria, Czech Republic and Hungary are located away from
the coast and are surrounded by land on all sides, hence are
called land-locked countries.
(C)
1. These mountains were covered by thick sheets of ice during
the great Ice Age, which were responsible for the general
lowering in height and the formation of rounded hills due
to ice erosion.
2. The highly rugged coastal areas of the North-West have deep
glacial valleys which have been drowned and then filled by
sea water.
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3. — Because of their low altitudes, Belgium and the Netherland
are called the low countries.
4. – During the Ice Age glaciers and ice sheets had covered
half of Europe and as they retreated, they eroded the land
to form long hollows, which later got filled in with water to
form lakes.
(D)
1. The Alpine mountain systems are the young fold mountains
running east-west as a series of parallel ranges lying south of
the Central Highlands between the Atlantic Ocean and the
Caspian Sea. They have steep slopes, narrow deep valleys
and high jagged peaks. The mountain system also includes
the Cantabrian mountains of Northern Spain the Sierra
Nevada in Spain, the Pyrenees between Spain and France,
the Apennines extending southwards in Italy. On the eastern
side there are two branches—the Carpathian in Slovakia,
Poland, Ukraine and Romania and the Balkans (in Bulgaria
form another branch. The Dinaric Alps runs southwards into
the Balkan Peninsula and the Pindus mountains in Greece.)
2. Europe is made of a few more peninsulas lying along the
coastline—the Scandinavian peninsula, the Iberian peninsula
and the peninsulas of Italy and Greece with its many islands,
hence the name "peninsula of peninsulas". Therefore Europe
is known as "peninsula of peninsulas".
3. The Alpine Mountain Systems are young fold mountains
running east-west as a series of parallel ranges lying south
of the Central Highlands between the Atlantic Ocean and the
Caspian Sea. They have steep slopes, narrow deep valleys
and high jagged peaks.
The North Western Highlands consist of high land system
running from Finland through Norway to Scotland. These
are the oldest mountain systems of Europe made up of old
and hard rocks. These mountains were covered by thick ice
sheets of ice during the great Ice Age, which were responsible
for the great lowering in height and the formation of rounded
hills due to ice erosion.
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Unit 3—Europe
Chapter 8: Europe—Climate and Vegetation
Exercises (on page 82)
(A)
1. Tropical type
2. North-west part
3.Westerlies
4.Steppes
5. Wild cats
(B)
1.Tundra
2.Westerlies
3.Olive
4.Steppes
5. North Atlantic Drift
(C)
1.Temperate
2.Temperate
3. Tundra/Arctic type
4.Westerlies
5.Coniferous
(D)
1. Many factors like relief features, distances from the sea,
direction of winds and the warm North Atlantic Drift affect
the climate of Europe.
2. The climate of Europe is of a temperate kind with a maritime
climate prevailing on the western coasts and a Mediterranean
climate in the South. Eastern Europe has a drier continental
climate.
3. The winters are long and bitterly cold; much of the area
remains under permanent cover of snow and ice.
4. Due to the extremely cold conditions, the region is generally
covered with thick layers of snow throughout the year.
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Unit 3—Europe
Chapter 9: Europe—Resources and Utilisation
Exercises (on page 94)
(A)
1. Market gardening
2.Flax
3. National and international highways
4.Transhumance
5. Channel Tunnel
(B)
1. Newsprint and matchsticks
2. Wells/Dykes
3. Dogger Banks/Great Fishing Bank
4. Rotterdam in Netherland
5. Floating factories
(C)
1. Extensive Farming—Where population is scanty and land is
available for cultivation, machines are used on large farms
covering several thousand hectares in areas. Wheat is mostly
cultivated in this farming. Extensive farming is practised in
the steppe region of Russia and Ukraine.
Intensive Farming is carried out in those areas where the
population is dense. The pressure on the land is heavy and
little land is available for agriculture. Small farms produce
high yields as improved methods of farming are used. These
include:
(i) better varieties of seeds.
(ii) better fertilisers and insecticides
(iii) practice of crop rotation
2. Viticulture is the practice of growing grapes in vineyards.
Grapes are used for making wines, raisins and currants.
Horticulture deals with the cultivation of fruits, flowers and
vegetables on a commercial scale.
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3. Market gardening is the small-scale production of fruits,
vegetables and flowers as cash crops, near large cities for
urban markets.
Mixed farming is the practice of growing crops and rearing
animals on the same field at the same time.
4. Crop rotation is the growing of different crops on the same
field alternately to maintain the fertility of the soil naturally.
Pastoral farming—Rearing of animals for commercial
purposes is called pastoral farming.
(D)
1. Suburban and underground stations are used for local travel.
2. The mild climate of north-western give rise to luscious soft
grass.
3. Mild winters and dry summers favour the growth of various
fruits, especially wine.
Unit 4—Asia
Chapter 10: Asia—The Land
Exercises (on page 102)
(A)
1. Rivers that drain northwards into Arctic Ocean—The
Northern part of the plain is called the Siberian Plain and
is drained by the three rivers – Ob, Yenisei and Lena. These
plains are formed mainly by the deposition brought by these
rivers. As the rivers are flowing northwards their lower
course and delta remain frozen during the winter.
Rivers that drain eastwards into the Pacific Ocean—The eastflowing rivers have formed a great plain by the deposition
of the rivers Huang He (Hwang Ho), Chang Jiang (Yangtze
Kiang) and Sikiang.
2. Aral Sea—The southern part of the Siberian plain which is
a lowland around the Aral Sea is called the Turan plain. It is
drained by the rivers Amu Darya and the Syr Darya, which
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flow into the Aral Sea. The Aral Sea is an inland sea and this
land-locked area forms an area of inland drainage.
Persian Gulf—Both the rivers, Tigris and Euphrates drain
into the Persian Gulf. This river valley is known as the
Mesopotamian lowlands.
3. Pamir Knot—To the south of the northern lowlands lies a
complex system of young fold mountains with plateaus in
between extending from the east to west. The entire ranges
seem to converge on the nodal uplift known as the Pamir
Knot on the Pamir Plateau. From here several south central
Asian mountain ranges branch out in all directions.
Armenian Knot—lies west of the Elburz mountains.
(B)
1. Asia extends between latitudes 10°N and 80°N and from
longitudes 26°E to 170°W.
2. Russia and China are the largest countries. Maldives and
Singapore are among the smallest.
3. Eurasia—The combined land mass of Asia and Europe.
4. River flowing into the
Pacific Ocean—Huang He (Hwang Ho), Chang Jiang (Yangtze
Kiang) and Sikiang
Arctic Ocean—Rivers Ob, Yeimesi and Lena.
Indian Ocean—Rivers Ganga and Brahmaputra.
5. East of the Pamir Knot, between the Kunlun mountains and
the Himalayas, lies the Tibetan Plateau. This plateau is the
highest plateau in the world and is called the "roof of the
world".
6. An archipelago is a group of islands lying near the coast of
a continent. The Indonesian archipelago, the largest in the
world extending for 5120 km, consists of five large islands–
Sumatra, Java, Borneo, Sulawesi, Bali and Timor and 30
groups of small islands.
(C)
1. Most of these rivers bring down large amounts of alluvium
and deposit them to form extensive depositional plains.
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2. Its wide variety of relief, climate, natural vegetation, religion
and cultures gives it this unique identity.
3. The water coming from their upper course, which is in the
warmer south, is thus blocked and spreads over large parts
of the plains forming swamps and marshes.
(D)
1.Tibet
2. Ural mountain
3. Western Ghats
Difference between Rivers draining the Northern Plains and
the Peninsular Plateau
Rivers of the Northern Plains
Rivers of Peninsular India
These rivers have their origin in
the Himalayas and are fed by the
rain and melting snows. They are
therefore perennial.
These rivers are rain fed as there
is no snow in the highlands of the
peninsular plateau. These rivers are
seasonal.
These rivers are long, perennial and
slow flowing over the vast plains.
They can be used for irrigation as
well as navigation.
These rivers cannot be used for
irrigation or navigation as they are
seasonal and dry during summer
and fast flowing.
These rivers are slow flowing and These rivers are fast flowing and
easy to navigate but are prone to have deep valleys and waterfalls
floods.
along their courses. They are not
navigable, but are not prone to
floods.
Unit 4—Asia
Chapter 11: Asia—Climate and Vegetation
Exercises (on page 112)
(A)
1.summer
3.equatorial
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2.steppes
4.equatorial
21
5.winter
6.equatorial
(B) 1. Tropical monsoon climate
2. Mediterranean climate
3. Cool temperate climate/Taiga region
4. The Great Panda
5. Tropical monsoon
(C)
1. Oceans are much cooler and a high pressure area develops
over them.
2. Due to lack of moisture, desert vegetation, known as
xerophytes, are found scattered over the region. They have
natural adaptation to the harsh climate. They have long roots,
spiny leaves and waxy stems to collect and absorb as much
moisture as possible.
3 The region experiences short warm summers, long cold
winters and light rainfall, in the form of snow, which is heavy
during winter, giving rise to several small and medium-sized
fur-bearing animals.
4. The Pacific Ocean and Indian Ocean are much cooler and a
high pressure area develops over them. Winds, therefore,
blow from sea to land and bring heavy rain to many parts
of south Asia.
5. Due to its long severe winters and frozen sub-soils, the tundra
is a black and treeless place.
6. In the drier regions, with moderate rainfall, the forests become
less dense and scattered.
(D)
1. Factors influencing the climate of Asia:
(i) Distance from the equator,
(ii) Distance from the sea,
(iii) Relief and altitude,
(iv) Winds,
(v) Ocean currents.
2. Due to the rise in temperature a low pressure develops over
this area. The Pacific Ocean and Indian Ocean are much
cooler and a high pressure area develops over them. Winds,
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therefore, blow from sea to land and bring heavy rain to
many parts of South Asia. These winds are known as the
south-west monsoons.
3.Table 11.1 Major climatic regions: Flora and fauna
1.
Equatorial
Malaysia,
Indonesia
and southern
Philippines
No marked
seasons. Normal
temperatures of 28
to 30°C
4 o'clock
shower
throughout
the year
Dense
evergreen
forest.
Mahogany,
ebony,
rosewood,
coconut and
rubber
Monkeys,
apes,
elephants,
wild cats,
colourful
birds and
reptiles
2.
Tropical
monsoon
Indian subcontinent
Hot wet
Cool
dry
Rainfall by
monsoon
winds
Tropical
deciduous/
monsoon
forest. Teak,
sal, shisham
and mango
Elephants,
bears, deer,
apes, lions,
tiger and
leopard
3.
Tropical
hot desert
Arabia, Thar
desert and
Iran
Hot dry
Cool
dry
Less than 25
cm of rainfall
Bushes,
shrubs, cacti,
clumps of
dry grass
Camels,
horses, mules
and insects
4.
Temperate
mild
latitude
desert
Gobi plateau
and Plateau of
Tibet
Very hot
Very
cold
with
temp.
below
0°C
Very little
rainfall
Tufts of
coarse short
grass and
thorny
bushes
Yak, lizards,
insects and
rodents
5.
Mediterranean
West Asia,
Turkey,
Lebanon and
Syria
Warm
dry
Cool
wet
In winter
due to
shifting of
wind belts
Oak,
chestnut,
walnut, olive
and fruit
trees
Donkey,
sheep and
cattle
6.
Warm
temperate
East coast/
China
type
China, Japan
and Korea
Hot wet
summer
Cool
dry
winter
Rainfall in
summer
Mixed forest
Oak, beech,
fir, chestnut
and bamboo
Monkey, foxes
and birds
7.
Temperate
Grassland
(Steppe)
Caspian Sea
of Russia
and eastern
Mongolia
Hot dry
Cold
dry
Rainfall from
25 to 75 cm
Short grasses,
wheat, barley
and other
food grains
Donkey, horse
and cattle
8.
Cold
Temperate/
Taiga
Sub-arctic
region of
Syria
Short
cool
Long
cold
Snowfall
Coniferous
Trees – Pine,
fir, spruce
and cedar
Sable, fox,
bear and
mink
9.
Arctic /
Tundra
Region
beyond Arctic
Short
cold
Long
severely
cold
Heavy
snowfall
Mosses and
lichen
Polar bear,
deer, foxes,
seals and
walrus
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4. Equatorial Natural Vegetation – Due to the heat and plentiful moisture, the vegetation grows abundantly rapidly. This
makes it impenetrable. The trees do not shed their leaves and
gives an evergreen appearance. The forests have large variety
of trees scattered all over; they are dense with broad-leaved
trees. The trees are tall and their branches form canopy and
do not allow sunlight to penetrate thus making the forest
dark.
Tropical deciduous or monsoon forests grow here which are
influenced by the seasonal amount of rain. Vegetation is thick
and mainly deciduous type. They shed their leaves in the dry
winter season. Areas with heavy rain have evergreen and
deciduous type and the forests are quite dense. The trees are
hardwood and broad-leaved. The tropical monsoon forests
also have trees like acacia, tall grasses and scrub vegetation.
5. Due to the heat and plentiful moisture, the equatorial
vegetation grows abundantly and rapidly. The growth of
dense vegetation makes the forests impenetrable. The forests
have a large number of species scattered all over. The trees
are tall and their branches form a canopy and do not allow
sunlight to penetrate, thus making the forests quite dark and
impenetrable.
Unit 4—Asia
Chapter 12: Asia—Resources and Utilisation
Exercises (on page 127)
(A)
1. It connects St. Petersburg and Moscow in Western Russia in
Europe to Vladivostok in Eastern Russia.
2. Two main races of Asia—Aryans and Dravidians
3. Natural resources and technical expertise
4. China and India
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5. Exports industrial goods as computers, TV sets, clocks,
watches, cameras, ship, automobiles and textiles.
(B) 1.False
2.True
3.True
4.True
5.False
(C) 1. Coal and petroleum.
Coal – raw material for chemical industry
Petroleum – petrochemical industry.
2. Plantation farming is a highly specialised method – farming
is carried out on huge farms called estates. A large capital is
required, modern scientific techniques are incorporated. All
the work of growing, harvesting, processing and packing are
carried out on the premises. Much work is done manually,
so a large number of labourers are employed. Production is
also on a large scale as these cash crops are chiefly grown
for export.
3. The long rivers in South and South-east Asia are some
of the important inland waterways. The Rivers Ganga,
Brahmaputra, Irrawaddy, Salween, Mekong are some of the
busiest waterways.
4. Family planning measures are being spread throughout
rural and urban areas. Health care centres are coming up in
remote parts, so that all are able to plan their families.
5. Today, the United Nations Organisation (UNO) along with
the governments of different countries is taking steps to
control the rapid growth of population. Among the steps
undertaken are:
(i) Education for all, especially women.
(ii) Family planning.
(iii) Abolition of child marriage.
6. The long coastline of Asia and the opening of the Suez Canal
have led to the development of many ports which has helped
to connect East Asia and South Asia to America by the Pacific
Route and South – East Asia and West Asia to parts in Europe
and Africa by the Suez Canal Route.
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25
Aden (Yemen), Mumbai.
7. Rice and wheat are the major staple food for the entire
continent.
The high temperatures and precipitation levels of South-east
Asia are the perfect conditions for the production of rice.
8. Shifting agriculture is harmful for the environment because
the burning of the forest creates pollution. Another name for
this agriculture is known as slash-and-burn agriculture.
(D)
1. –Of the extreme climatic conditions.
2. – Railways are the cheapest means of transportation of bulky
goods over long distances.
3. – European countries—The British, Dutch, Portuguese and
French—all had trading posts in many Asian countries. Their
whole idea of coming to Asia was trade and commerce.
4. – To avoid the stagnation of water.
5. – The land is covered with thick snow.
6. – Therefore Japan imports most of the industrial goods
required.
7. Varied geographical conditions – soil, climate, water resources
and economic conditions – have led to various types of
agricultural methods.
Crop
Climatic conditions
Areas (at least 2)
Rice
Hot and wet climate, India and China
heavy rainfall
Wheat
Cool, moderate rainfall Northern China, India
Tea
H i g h t e m p e r a t u r e , India, Bangladesh
heavy rainfall
Sugar cane
Hot and moist climate, India, Java
Bright sunshine.
Cotton
High temperature,
sunshine, frost-free
days
China and Pakistan
Rubber
High temperature,
heavy rainfall
Malaysia, Indonesia
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(G)
1. Shifting agriculture
2. Plantation agriculture
Unit 5—India
Chapter 13: Location, Extent & Physical Features
Exercises (on page 143)
(A)
1. b. Himachal Pradesh
2. c.Kerala
3. b. Sri Lanka
4. c. Zaskar Range
5. d.Jhelum
6. b.Godavari
7. b.Kosi
(B)
1. Western Ghats
2.Indus
3.Karakoram
4. Khasi Hills
5. Aravalli Range
6. Andaman and Nicobar Islands
(C)
1. 8° 4' N and 37° 6' N
2. Tropic of Cancer
3. Yarlung Tsangpo
4.Sahyadhri
5.Kanyakumari
6.K2 Godwin Austen
(D)
1. Aravalli Range
2. Ten Degree channel
3.Godavari
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4. Himadri or the Greater Himalayas
5. Narmada River
6.Karakoram
(E)
1. (i) Acts as a climatic barrier.
(ii) Glaciers and snow fields are sources of many perennial
rivers.
(iii) Fertile alluvial soil.
(vi) Tourist centre.
(v) Mineral resources.
(vii) Numerous hill stations.
2. Fertile alluvial soil deposited by the rivers and the perennial
rivers provide easy transport/good network of roads helping
to make the area have a dense population.
3. They depend on the monsoon rain for water. They are less
suitable for irrigation and are not easily navigable.
(F)
1. Eastern Ghats
(i) They are broken by the valley of rivers flowing into the
Bay of Bengal extending from the Mahanadi valley to
the Nilgiris.
(ii) They are much lower with their average height being
about 450 m.
(iii) They have gentle slopes and rise from much wider
eastern coastal plain.
Western Ghats
(i) They are continuous, extending from the Tapi River to
Kanyakumari.
(ii) They are much higher, their average height being around
1200 m, but rising to 2500 m in some parts.
(iii) They are steep and rise abrupetly sharply from a narrow
western coastal plain.
2. The Himalayan Rivers—Originate from the snow capped
mountains and have drainage basin consisting of the Indus,
the Ganga and the Brahmaputra and their many tributaries.
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The Peninsular Rivers—are classified into two as the westflowing rivers and the east-flowing rivers. These rivers are
short, swift-flowing rivers.
3. The Eastern Coastal Plains
Lie between Bay of Bengal and Eastern Ghats. It is wider and
extends from the mouth of River Ganga to Kanyakumari.
The northern part of the coast between Rivers Mahanadi and
Krishna is known as Northern Circars. The southern part
between the Krishna and Kaveri is called the Coromandel
Coast. There are several lagoons and lakes – Lake Chilika
Kollery. Lake and lagoons are known as the backwaters in
Kerala. Lake Vembanad is the largest coastal lagoon.
The Western Coastal Plains—Lie between the Western Ghat
and the Arabian Sea stretching from Kutch in the north to
Kanyakumari. The western coast is known as the Gujarat
coast, the Konkan Coast in Maharashtra and the Malabar
Coast in Kerala. The Konkan Coast is broader and has the
largest seaport.
Unit 5—India
Chapter 14: India—Climate and Vegetation
Exercises (on page 158)
(A)
1. b.Ebony
2. b. Evergreen rainforests
3. b.Acacia
4. c.Sundari
5. a. Deltas
6. b. deciduous forests
7. a. coniferous forests
8. a.Sundari
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9. a.Kangaroo
10. b. Madhya Pradesh
(B)
1.South-westerly
2. Kaal baisakhi
3. Break of monsoon
4. Western depression
5.Biosphere
6. Tropical deciduous forest
(C)
1.Mawsynram
2.Mediterranean
3. Peacock, Bengal tiger
4. Teak and Sal
5. Western side of the Western Ghats
(D)
1. Windward side
The mountain slopes facing the rain-bearing clouds receive
rain and are called the windward side.
2. Rain-shadow area
Region not receiving much rain as it lies on the leeward side
of a mountain barrier.
3. 'Break in the monsoon'
The rainy season may not be a continuous one. At times there
may be break between spells of rain.
4. National parks
These are protected area reserved exclusively for preserving
the flora and fauna, landscape and buildings and monuments
of historic importance of an area.
5. Natural vegetation
Plants that grow on its own under the influence of climate
and soil.
(E)
1. Due to the lapse rate, the temperature decreases with increase
in altitude. For every 1,000 metres of ascent there is a drop
of 6°C in temperature.
2. Delhi is away from the sea and has an extreme climate,
whereas Mumbai located along the coastal region and have
an equable climate.
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3. Due to human activities.
4. The Bay of Bengal branch bring heavy rain to the Garo-KhasiJaintia as they get trapped in the funnel-shaped arrangement
of the hills.
5. Due to large-scale cutting down of trees called deforestation.
6. Winters are dry in northern India. When north-east winds
blow over the Bay of Bengal they pick up to became northeast monsoons and bring rain to the Coromandel coast.
7. The most extensive tidal forest area is found in the GangaBrahmaputra delta called the Sunderland after the Sundari
tree that grows here.
(F)
1. Monsoon rains are characteristically irregular. They are
irregular in terms of time of occurrence, distribution, amount,
which vary from year to year. The rainy season may not be a
continuous one. At times there may be break between spells
of rain.
2. Himalayas are called a climatic divide –
(i) Himalayas stops the moisture-bearing South-westerly
winds to go across the Himalayan mountain and shed
the moisture at the foothills of the Himalayas.
(ii) Himalayas stops the cold Arctic winds from entering
into India.
3. Tropical deciduous forest is common in India. The
important trees are teak, sal, ebony, mahua, deodar, palash,
peepal, sandalwood, etc.
4. Thorn forest is found in areas where the annual rainfall
varies between 50 and 100 cm. Mostly thorn bushes,
acacia and grasses are found. The vegetation consists of
widely scattered and short trees like acacia. The leaves
are waxy, spicy and thorny to reduce transpiration and
loss of water, their roots are long so that they may go
deep in search of water.
5. (i) The summer monsoons—March–June
(ii) The winter season—November–February
6. Forests are important (1) because trees produce a
large amount of oxygen, (2) Trees act as natural air
conditioners.
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7.Relief features cause great variations in its distribution.
These winds can cause flood in one part and drought in
another part simultaneously.
Unit 5—India
Chapter 15: India—Case Studies
Exercises (on page 171)
(A)
1. Rabi
2. white sap (latex), Hevea brasiliensis
3. financial capital
4. Information Technology
5.broadcasting/dibbling
6.Kerala
7.Nylon/Terylene
8. Texas Instruments/Lucent Technologies
(B)
1. (i)Plantations need large amounts of capital for preparing
the land, planting the crops, hiring labour and
establishing processing factories.
(ii) A large number of workers are employed in
administration, technical services and labour.
(iii) Advanced technology is used—machines for planting,
harvesting and laboratories to check the quality of the
products.
(iv) Good transport links, especially with ports, are also
necessary.
2. Factors favouring wheat cultivation in Punjab:
(i)Ideal climatic conditions: The temperatures average
about 10°C–15°C during the sowing seasons in OctoberNovember and around 20°C in February–March, the
harvesting season.
(ii) Ideal rainfall: It has rainfall around 15 cm. Punjab also
experiences winter rain which is especially beneficial to
the crop.
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(iii) Good irrigation facility: Close network of canals and
large number of tube wells.
3. Green Revolution: A package offered to wheat farmers which
enables, them to increase their production of wheat many
fold.
4. (i) Its strategic location
(ii) Easy availability of raw material
(iii) Cheap hydroelectricity and soft water for dyeing and
bleaching
(iv) Cheap unskilled labour
(v) Major port
(vi) A good network of roads and railways
(vi) Humid climate is ideal for spinning of yarn
(viii)Parsee and Gujarati merchants provide capital
5. (i) It has the largest and widest availability of skilled
managers with work experience.
(ii) Large number of educational institution and information
technology colleges.
(iii) Climate is moderate which attracts foreign companies.
(iv) Good transport network, good telecom connectivity
advanced infrastructure, better state policy and invester
perception.
(v) Dust-free with low rent and low cost of living.
(vi) The state government of Karnataka was the first to
announce an IT policy in 1992.
(C)
1. Pepper, cardamom, clove, chilli, ginger, turmeric (any two)
2. Jalandhar, Ludhiana, Sangrur, Amritsar, Bhatinda, Firozpur,
Patiala, Gurdaspur (any 2)
3. Ahmedabad, Gujarat, Coimbatore, Kolkata, Kanpur,
Ludhiana, Chennai, Panipat (any 2)
(D) 1. (i) Mumbai factories had old and obsolete machinery, the
production of which was low and the industry became
uneconomic and sick.
(ii) Mumbai faced stiff competition from other countries like
Egypt, Sudan, Kenya Uganda and Tanzania, which grows
fine long-stapled cotton and produced quality fabrics.
TH—Our Earth—8
33
(iii) Mumbai cotton became expensive. Raw cotton was a light
commodity which was quite cheap to transport to other
counties that produced better and cheaper cloth.
(iv) The increasing demand for synthetic textile like rayon, nylon,
terylene, etc. was another cause for the setback of the cotton
textile industry in Mumbai.
2. Parts of Worlds—
(i) The USA—Cotton
(ii) Sri Lanka—Tea
(iii) Brazil—Coffee
(iv) Kenya—Coffee
(v) Ghana—Cocoa
(vi) Malaysia, Indonesia—Rubber, coconut
(vii) Queensland, Australia—Sugar cane
2.
a. Plantation farming is practised in selected parts of the world
because large amount of capital, good transport links, skilled
and unskilled cheap labour and other favourable conditions
are hard to be found everywhere easily.
Plantation farming is expensive—It is totally commercial type
of farming grown on large farms involving the growing of
mainly cash crop. Plantation farming is expensive because
it needs large amount of capital for preparing land, planting
the crop, hiring labour and establishing processing factories.
3. (i) The largest and widest availability of skilled managers
with work experience.
(ii) Largest number of educational institutions and
information technology colleges.
(iii) Climate is moderate throughout the year, which attracts
foreign companies.
(iv) Good network of transport, good telecom connectivity
advanced infrastructure and better state policy and
investors perception.
(v) It is dust-free with low rents and low cost of living.
4. The western distrubances are beneficial for Punjab average
wheat crop because the rain in winter season. Winter
rainfall in this region is 15 cm, which is ideal for wheat
crop.
34
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