scsvshsstclass5e(20.5) part 4

REALMS OF THE EARTH    -    REVISION

May 22, 2020

On completion of the lesson , you are able to:

# list the four spheres of the Earth

# explain key features of the Earth

# understand the components of the Earth

Today, we are going to do the recap of what we have learnt in the chapter.

Copy the work in your notebook and give the heading as REVISION

Question 1:

Name the four realms of the earth.

ANSWER:

The four realms of the Earth are as follows:

(1) Lithosphere: 

•  It is the hard, rocky outermost shell of the Earth made up of rocks and soil. 
•  It is composed of the crust, mantle and core.
• Almost three-fourths of the total area of the Earth is covered by water and the remaining one-fourth is covered by land.

(2) Atmosphere:

•  It is the air or the layer of gases that surrounds us. 
• Air is essential for survival.

• The main constituent of the atmosphere is nitrogen, which is followed by oxygen  and gases such as carbon dioxide

(3) Hydrosphere: 

• It is the mass of water found on the Earth that includes oceans, rivers, lakes,  etc. 
• It includes water in all forms.
• It also includes ice caps of the polar regions, underground water and water vapour in the air.

(4) Biosphere: 

• The zone where land, water and air come in contact with each other to support life and where living organisms inhabit is called the biosphere.
• It overlaps all the other three layers.

Question 2:

Name the five layers of the atmosphere.

ANSWER:

The atmosphere is divided into five layers. The layer that is closest to the Earth is the troposphere, followed by the stratosphere, the mesosphere, the thermosphere and the exosphere. All layers vary in thickness and are divided on the basis of their temperature, chemical composition, etc.

Question 3:

Write the difference between lithosphere and hydrosphere.

ANSWER:

Lithosphere	Hydrosphere
It is the outermost layer of the Earth that is composed of crust, mantle and core.	It is a mass of water found on the Earth that includes oceans, rivers, lakes .
Almost three-fourths of the lithosphere is covered with water, while the rest is covered with land.	It nearly covers 71 percent of the Earth's surface.Water, in all its forms is constantly moving.

Now, its time to do some brain exercise.

 

This is all for today !!