Page 123 - SST Class 06

Major Domains

of the Earth 19

q Lithosphere (distribution of continents) q Atmosphere (composition and importance)
q Importance of Biosphere q Hydrosphere (distribution of oceans)

Introduction LITHOSPHERE

Earth is unique in the Solar System as being the only Lithosphere comprises all types of land masses,
planet which is able to support life in all its forms— big or small, low or high. It comprises high
from basic living micro-organisms to highly mountains, plains, plateaus and valleys. It is the
sophisticated and intelligent human beings. Life has top crust of the Earth. This Earth’s crust can be
become possible on this planet only due to the divided into two—the land masses and the ocean
presence of land, water and air in just right beds. The thickness of lithosphere ranges from 6
amount. These are called the three domains of to 60 km.
lithosphere , hydrosphere and atmosphere The highest point in the lithosphere is Mount
respectively. The domain where these three Everest (8848 m) and the deepest point is Mariana
domains meet and create conditions favourable
Trench (11022m). The land masses constitute
to the origin and support of life, is called nearly 29 percent of the Earth’s surface, while
biosphere . Thus, there are a total of four about 71 percent of the surface is under seas and
domains. We shall study them in brief.
oceans.

ARCTIC OCEAN ARCTIC OCEAN

ARCTIC CIRCLE ARCTIC CIRCLE

NORTH EUROPE
AMERICA ASIA NORTH
NORTH PACAFIC
ATLANTIC OCEAN
OCEAN
TROPIC OF CANCER TROPIC OF CANCER
NORTH
PACAFIC
AFRICA
OCEAN
EQUATOR EQUATOR
INDIAN OCEAN
SOUTH
AMERICA
TROPIC OF CAPRICORN SOUTH TROPIC OF CAPRICORN SOUTH
ATLANTIC PACIFIC
AUSTRALIA
SOUTH OCEAN OCEAN
PACIFIC
OCEAN

ANTARCTIC CIRCLE
ANTARCTICA
Continents and oceans
Major Domains of the Earth
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