Grade 6. chapter 5. realms of the earth.. The Earth divided into 4 realms which are interconnected. The names of the 4 spheres have been derived from Greek words for stone (litho), air (atmo), water (hydro), and life (bio) The layer of the gas that surrounds the Earth is called atmosphere. The atmosphere protects Earth from absorbing the harmful ultraviolet rays of the Sun. It also acts as a blanket around the Earth.

1. Grade – 6 – Social
Science
Chapter – 5- Realms of
the Earth
Prepared By : Navya Rai

2. Introduction
The Earth divided
into 4 realms which
are interconnected.
Atmosphere
• A layer of
gas that
surrounds
the earth
Hydrosphere
• Water
bodies on
our planet
Lithosphere
• Rocks of
the earth’s
crust and
thin layer
of the soil
Biosphere
• Which
comprises
all living
organisms
The names of the 4
spheres have been
derived from Greek
words for stone
(litho), air (atmo),
water (hydro), and
life (bio)

4. Atmosphere
The layer of the gas that
surrounds the Earth is
called atmosphere.
The atmosphere
protects Earth from
absorbing the harmful
ultraviolet rays of the
Sun.
It also acts as a blanket
around the Earth.

5. Composition of the Atmosphere
In the atmosphere,
nitrogen and oxygen
are found in bulk
quantities.
Carbon dioxide,
helium, ozone, argon
and hydrogen are
found in lesser
quantities.

6. Layers of the Atmosphere
Montreal
Protocol was
adopted in 1987 to
protect the ozone
layer from
depleting.

7. This layer is the most
important layer of the
atmosphere.
Its average height is 10
to 12 km and the air we
breathe exists here.
In this layer, all-
weather phenomena
like rainfall, fog and
hailstorm occur.
Troposphere

8. Stratosphere
Above the troposphere
lies the stratosphere.
It extends up to a height
of 50 km.
This layer is free from
clouds and associated
weather phenomenon,
which makes it most
ideal for flying
aeroplanes.
It contains a layer of
ozone gas.

9. Mesosphere
➜ This is the third layer of the
atmosphere.
➜ It lies above the stratosphere.
➜ It extends up to a height of 80
km.
➜ Temperature is here -85℃ so
its causes to formation of ice
clouds called noctilucent clouds.
➜ Meteorites burn up in this layer
on entering from space.

10. thermosphere
In thermosphere, temperature
rises very rapidly with
increasing height.
Ionosphere is a part of this
layer. It extends between 80-
400 km.
This layer helps in radio
transmission.
Beautiful natural phenomenon
of lights occurs in the skies
called aurora.
Auroras also have
been observed on
Jupiter’s moon lo.

11. Aurora

12. Exosphere
The uppermost layer
of the atmosphere is
known as exosphere.
This layer has very
thin air.
Light gases like
helium and hydrogen
float into space from
here.

13. lithosphere
The lithosphere is the outer solid part of the earth,
including the crust and uppermost mantle.
The crust covers the entire surface of the Earth and
the beds of the seas and oceans
It floats upon a softer layer called the asthenosphere.
The crust is made up of two layers
Upper layer called sial.
Lower layer called Sima.
About 71% of the total area of lithosphere is covered
with water and the remaining 29 % is occupied by land.

15. Mountains
Mountains are landforms that rise abruptly
above the surroundings land, forming a peak at
the top.

16. Hills
Hills are like mountains but not as steep, large
and tall as the mountains.
Eg: Shivalik hills, Anamalai Hills, Biligirirangana
hills

17. plateaus
In geology and physical geography, a plateau,
also called a high plain or a tableland, is an area
of a highland, usually consisting of relatively flat
terrain, that is raised significantly above the
surrounding area, often with one or more sides
with deep hills.

18. Plains
A plain is a flat, sweeping landmass that generally
does not change much in elevation.
Plains occur as lowlands along valleys or on the
doorsteps of mountains, as coastal plains, and as
plateaus or uplands.

19. Hydrosphere
A hydrosphere is the total amount of water on a
planet.
The hydrosphere includes water that is on the
surface of the planet, underground, and in the
air.
A planet's hydrosphere can be liquid, vapor, or
ice.
On Earth, liquid water exists on the surface in
the form of oceans, lakes and rivers.

21. Importance of the hydrosphere
It plays a key role in the water cycle of the Earth.
It provides fresh water which is our basic need for survival.
It provides a cheap and easy means of transportation.
It plays a key role in weathering and erosion of rocks in the
lithosphere.
It is a storehouse of mineral wealth.
The aquatic organisms in the hydrosphere are important
sources of food.
The oceans contain organisms which are of great medicinal
value.

22. Biosphere
The biosphere, also
known as the
ecosphere, is the
worldwide sum of all
ecosystems.
It can also be termed
the zone of life on
Earth, a closed
system, and largely
self-regulating.

23. Realms of the earth
Biosphere
Atmosphere
HydrosphereLithosphere