7 Chapter - 2.Geography. The Earth and the Changes.Questions/Answers.

 Chapter - 2.Geography.

The Earth and the Changes.

Questions/Answers.
A.Tick (√) the correct option
1.Which one of the following is not a human activity
(a) Diverse land use
(b) Cleaning of forest
(c) New human settlements
(d) Formation of mountains
2. Which one is a continental glacier?
(a) Siachin
(b) Antarctica
(c) Gangotri
(d) Yamunotri 
3.Which of the following features are formed by a river?
(a) ‘V’ shaped valley ,meander and delta
(b) ‘U’ shaped valley, meander and delta
(c) ‘I’ shaped valley, cliff and delta
(d) ‘V’ shaped valley, meander and sand dunes
4.Which layer of the soil contains humus?
(a) Bed rock
(b) Weathered rock
(c) Sub soil                           
(d) Top soil
5. Which soil type is capable of retaining moisture and becomes sticky when wet?
(a) Alluvial soil
(b) Black soil
(c) Red soil
(d) Laterite soil

B.Fill in the blanks.
Q1.Organic matter when gets decomposed in the soil and converts it into dark coloured material is called humus.
Q2.Alluvial soil is found in a large part of our Country.
Q3.‘I’shaped and ‘V’shaped  valleys are formed at the Youthful stage of a river.
Q4.A cliffs is a steep sided rock facing the sea.
Q5.Ganga River and Brahmaputra River from the largest delta of the world.

C.Give a single term for each of the following statements.
Q1.Mounds of sand deposited by wind action in deserts Sand dune
Q2.The process in which a gradual wearing and carrying away of soil particles takes place   on the earth’s surface. Erosion.
Q3.The process of laying down of sediments carried by various agents of gradation. Deposition
Q4.A mass of moving ice down the slope. Glacier
Q5.Removal of the top layer of soil. Soil erosion

D. Answer the following question in brief.
Q1. Specify two differences between internal and external forces.
Ans-The sudden change originates inside the earth,due to volcanic or earthquake activities. Internal forces bring radical changes and are easily visible.
These changes usually take inside the earth.
On the other hand,some changes are very slow and take place gradually over a long time. This could be due to natural forces,such as carrying of soil by rain water, changes in the course of river, winds carrying soil particles with them, etc.
These bring changes on the surface of the Earth.
Q2. Name the various agents of gradation.
Ans - Agents of gradation are- Running water,Glacier, Wind and Sea water.
Q3. Distinguish between transported and residual soil.
Ans -The weathering process breaks the rock into small particles.These are then carried away by water, wind, etc and let’s get deposited at a new place. Such soil is called the  transported soil. 
But, when the soil is formed by the weathering of a parent rock and remains presents on the same site,it is called residual soil.
Q4. How is a delta formed?
Ans - The river,thus deposits silt, sand and sediments over a large area near its mouth. This large deposition helps in the formation of a delta. Ex – Sundarban Delta
Q5. Why is humus formed more rapidly in humid areas?
Ans - Humus is rapidly formed in humid areas due to heavy growth of pants and rich animal life.

E.Answer the following question.
Q1. Explain weathering. Mention the factors that affect the role of weathering and

soil erosion.
Ans- The term weathering refers to the process that breaks rocks into smaller

particles. It includes erosion and deposition.

Human factor can play an equally important role in changing the surface of the earth.

The example are cutting” down of forests, construction of roads, bridges and railway

line, large-scale bringing of dams, etc.

This could be due to natural forces, such as carrying of soil by rain water, changes in

the course of a river, winds carrying soil particles with them.
Q2. Explain the formation of soil with the help of a labelled diagram.
Ans - The soil forming process continues over a long span of time. It starts developing in
layers are called horizons. From bottom to top the lowest horizons is called bed rock. 
Then comes the horizons of weathered rock and it is followed by the sub soil and top soil.
The top most horizons is rich in humus.
Q3.What are the major soil types found in India? Give one important characteristic of each
Ans - Alluvial Soil is found in large part of India.This soil is very fertile.
Soil is generally classified on the basis of color texture.
Black soil is found in Deccan plateau.This type of soil is confined to some parts of Gujarat,
Maharashtra and Karnataka. It is popularity know cotton soil. 

         Red Soil is found over the hill slopes of peninsular plateau. The Laterite soil is found in the regions of heavy rainfall.

Desert & Mountain Soil are other types of soil.
Q4. Describe the journey of a river from its source to it mouth
Ans - It takes birth in a mountain or a hill. In its early stage, the river is young. It flows over
steep mountain where its rate of erosion is maximum. 
It forms striking youthful feature like 'I' and ‘V’ shaped valleys,waterfalls, etc. 
As the river enters into the plain, it comes to the stage of maturity. During this stage, the
river is said to flow through meanders. 
The river, thus, deposits, silt, sand and sediments over a large area near its mouth.This
large deposition helps in the formation of delta.
After that it gets mixed with the sea.

Q.5 why is conservation of soil important? Suggest three different ways of soil conservation.

Answer: The conservation of soil is important because the formation of soil is a very slow process. It takes thousands of years to form a thin layer of soil.

The three different ways of soil conservation are:

(i) Plantation of trees.

(ii) Development and management of pasture land.

(iii) Selective agricultural practices like crop rotation and multiple cropping

Inside questions answers.
1.What is External ?
Ans- Any process working on the earth's surface and bringing changes on it,is known as
external process.
2.What is Geomorphology?
Ans- Geomorphology is the science study of landforms.
3.Define Weathering.
Ans-The term weathering refers to the process that breaks rocks into smaller particles.
4.What does weathering include?
Ans-The weathering includes erosion and deposition.
5.Define Gradation.
Ans- Gradation means leveling of land.It occurs in two ways :- 
(a) Agradation
(b) Gradation
6.Define Agradation .
Ans- Agradation means adding of sediments and raising the level of land.
7. Define Degradation.
Ans- Degradation it means breaking and wearing away of sediments and lowering the level
of land.
8.What is Erosion?
Ans- Erosion refers to gradual wearing and carrying away of all those lose particles of
disintegrated rock which lie exposed on the earth's surface by the weathering agents of
gradation I.e. running water,wind, moving ice and sea waves.
9.What is Deposition?
Ans- Deposition refers to the laying down of sediments which have been carried from
distant parts of the earth's surface by various agents of gradation.
10.Name the Agents of Gradation.
Ans- The name of Agents of gradation are:-
(a) Running water
(b) Glacier
(c) Wind
(d) Sea waves
11. Define the process of Running water.
Ans- A river, like any living form,has a 'life cycle'.It takes birth in a mountain or a hill
,becomes larger where it met  by several number of tributaries , flows over plains and finally
ends when it reaches the sea.
12. What is Glacier?
Ans-The mass of moving ice is called a glacier.
13. Define the process of sea waves?
Ans- Sea waves are the most powerful agent of Gradation . The continuous striking of sea
waves breaks the rocks .such continuous erosion forms steep sided cliffs facing the sea.
14. Define Wind.
Ans- Wind is neither be seen or can neither be seen not felt but the swift horizontal
movement of air is felt and it is called wind.This forms sand dunes
15. What is Soil?
Ans- Soil is the loose material found on the surface of the earth . It is made up of  organic
and non-organic particles.
16.Define the transported  soil.

Ans- It is very slow process .it takes thousands of years to form a thin layer of soil. These
are carried by water,wind etc,and later get deposited at a new place. This type of soil is
called as transported soil.
17.Define the residual soil.

Ans- When the soil is formed by the weathering of the parent rock and remains present on
the same site, it is called as transported soil.
18.What are horizons?

Ans- The soil forming process continues over a long span of time . It starts developing in
layers, one over another . These layers are called horizons.
19.Define the Bed rock.

Ans- From bottom to top,the lowest horizon is called bed rock.
20.Define Weathered rock.

Ans- After bed rock the horizon comes is known as weathered rock.
21. The process of bed and weathered rock followed by which soils?

Ans - The process of bed rock and weathered rock followed by sub soil and top soil.
22.What is distribution of Major soil types.

Ans- Soil is generally classified on the basis of colour and texture .They are of many types
23.What is Alluvial soil?

Ans- It is found over a large part of India .This type of soil is very fertile and forms major
agricultural land of our country.
24.What type of soil is black soil?

Ans- It is found in Deccan plateau .It is largely used for growing cotton and thus,it is also
known as Cotton soil.
25.What type of soil is known as Red soil?

Ans- The soil is red in colour due to the presence of iron particles Red soil is confined to
peninsular India and some patches of north-eastern parts of India .It is highly porous ,fine
grained and deep.
26.What type of soil is known as laterite soil?

Ans- It is found over the hill slopes of peninsular plateau.The laterite soil is found in the
region of heavy rainfalls.It is formed by the leaching process.
27.What is soil erosion?

Ans- Removal of the top layer of the soil is called soil erosion.
28.What is Snow line?

Ans- The Snow line on the high mountains above which the snow never melts.
29.What is a cliff?                               

Ans:-The continuous striking of sea waves breaks the rock. Such continuous erosion forms
steep sided cliffs.
Map skill 
Locate and label the areas of major soil types in India.