CBSE Class 7 Social Science Collection of Assignments Set G

Chapter 1 Where, When and How

Question and answer

A. Short answer question.

Question. What are the………… country?
Answer: Different names of our country

Bharat varsha or bharat: derived from the name of bharata, who was the son of dushyanta and shakuntala. Hindustan: It basically means a place where huindus live.

Jambudvipa : it means land of jamun trees Nabhivarsha: It was named after Nabhiraja son of agnidhara the ruler of india India : this name is taken from French word ‘inde’.

Question. Which…………………..India?
Answer: The great Himalayas in the north always acted as a barrier against the foreign invasion.

But the mountain passes like Khyber and the bolan allowed travelers and invaders to enter India through the North West. The main invading tribes who came to India were the Turks, Afghans, Persian and the Mongols.

Question. How………………………….Period?
Answer: Coins from Medieval period gives us information about the different ruler of that time their interest and achievement. They study of coins is called Numismatics.

Question. Name……………………………Examples?
Answer: Ibn Battuta: A traveler from Morocco who wrote about Muhammad-bin-tughlaq’ rule in his travelogue ‘Rihla’. Sir Thomas Roe:An ambassador of British king James I, stayed at the court of mughal Emperor ‘Jahangir’. Domingo Paes: he was a Portuguese traveller9 who visited Vijayanagar Empire around the year 1520 AD.

B. Long Answer question

Question. What………………………detail?
Answer: The archaeological sources can be classified into various types

• Monuments: Monuments includes temples, mosques, forts, tombs, etc. They not only tells about the religious practices but also about the society its architecture, economic and political conditions.

• Inscription: The Inscriptions or epigraphs are the wrirings engraved on hard surfaces.

• Coins: coins from medieval period give us information about the different rulers of that time, their interests, achievement.

• Paintings: paintings are very important sources of history. They tell us about the customs, rulers and socio-political life of the period.

Question. How ………………………………..Period?
Answer: These were created within the country, these include manuscripts and chronicles.

• The manuscripts were mainly nwritten onplam leaves, cloth, brick bark and later, on paper as well.

• The chronicles were the record of urle of kings and their kingdoms.

• Bards were appointed by the kings for this propose.

• They used to record all the proceedings at king’s court, thus giving valuable information about the administration of that period.

• The languages used in these chronicles were mostly Persian and Turkish.

Question. What……………………………Period?
Answer: Major historical developments during the medieval period

• Many political groups emerged. Muslim invaders like Mahumad of ghazni and Muhammad Ghori and other Turks, founded the delhi Sultanate.

• Mughals were the most powerful Mongol rulers who uprooted the rulers of delhi sultanate and gave a kind of political stability to our country for a very long period of time.

• Changes were made at the social and economic levels. Extension of agriculture was marked by the gradual clearing of forests.

• Castes or jatis and sub caste gained prominence during this period.

C. Give reasons

Question. Writing………………………Information.
Answer: The account of foreign travelers proved to be an important source to know about the life of ordinary people. Some of the known travelers were Ibn Battuta, Marco Polo, Sir Thomas Roe, Abdur Razzaq.

D. Distinguish Between

1. Northern region and Sourthern region

2. Early medieval period and late medieval period

Chapter :- I
Our Environment

Distinguish between----

1. Physical and Human Environment

2. Lithosphere and Hydrophere

3. Biosphere and Ecosystem

Short answer questions--

Question. What do you mean by environment?
Answer:
1. Environment is our basic life support system.
2. It is made up of different components.
3. They can be broadly classified into two groups-a)Natural environment b) Human environment.

Question. What is an ecosystem?
Answer:
1. Ecosystem is a combination of two words, ecology and system.
2. It is the study of the interaction between living and non living things in a specific area.
3. An ecosystem includes all of the livings things and non living things.

Question. What is the relationship between environment and human beings?
Answer:
1. Human beings interact with the environment and modify it according to their needs.
2. Early humans adopted themselves to the natural surroundings and lived in harmony.
3. Human environment is the environment that is created by man for his better existence and growth

Question. Give two examples for each of the following----
Answer:
1 . Abiotic Environment—Land,water
2. Biotic Environment---Plant,animals
3. Human Evironment---Bridges roads

Question. Name any five ecosystems.
Answer:
1. Freshwater Ecosystem.
2. Marine Ecosystem
3. Tropical rainforest Ecosystem
4. Desert Ecosystem
5. Grassland Ecosystem

Question. What is biosphere?
Answer:
1.The narrow zone of the earth where land,waterand air interact with each other to support life is called biosphere.
2.It is a unique feature of our earth.
3.Because of this zone that life can exit and flourish on the earth.

Long answers questions

Question. Explain how is oxygen useful to us?
Answer:
1. Oxygen is a life supporting gas and it is used by all living things.
2. Human beings and animals inhale oxygen during breathing.
3. Plants breathe and absorbe oxygen during night.
4. During the day they give off oxygen by photosysthesis.
5. Oxygen cylinders are used by patients having breathing difficulty .
6. It is also used by mountaineers and divers in the sea.

Question. Write the significance of the biosphere?
Answer:
1. It is the narrow zone of the earth where land ,water and air interact with each other to support life.
2. It is a unique feature of our earth.
3. Because of this zone that life can exit and flourish on the earth.
4. This zone provides us all our necessities.
5. Outside the limits of the biosphere,life is not possible.

Question. What is the hydrosphere comprised of?
Answer:
1. The domain of water is reffered as Hydrosphere.
2. It is the part of the earth surface which is covered with water.
3. It includes all the water bodies such as oceans,seas,lakes,rivers and streams etc.
4. It also includes ice sheet in the polar.
5. High mountains regions,underground water and water vapours in the air.

Question. Briefly explain different constituents of natural environment?
Answer: Land (Lithosphere),water(Hydrosphere)and air (Atmosphere) along with plants and animals (Biosphere) are the different constituents of our natural environment.

IV Give reason for the following----
1. Man modifies his environment. For his better existence and growth.
2. Biosphere affects climate.
Due to exchange of green house gases in biosphere.
2. Imbalance in our environment.
Is due to environmental pollution.

Chapter - 2
The Earth’s structure

Distinguish between-

1. Intrusive and Extrusive Igneous Rocks--

2. Rocks and Minerals-

3. Magma and Lava--

Short answer questions

Question. Name some minerals found in sedimentary rocks?
Answer: Minerals are—
1.Sandstone
2.Shale
3.Limestone
4.Gypsum
5.Conglomerate

Question. What do you understand by sial,sima,nife?
Answer:
Sial—The main menerals constituents of the continental mass are silica and alumina.
It is called Sial.
Sima -The oceanic crust mainly consists of silica and magnesium, it is therefore called sima.
Nife- The core is made up of heavy metals like iron and nickel,and is called nife.

Question. Difine fossile.
Answer: Sedimentry rocks may contain remains of animals and plants, which sometimes get trapped in the layers of sediments. They are called fossils .

Question. How rocks and minerals are formed?
Answer: The rocks are formed when magma is extruded or forced out, onto the surface of the earth and becomes lava and form minerals in it form very small crystals and thus these rocks very fine grained.

Question. How rocks and minerals are useful to us?
Answer:
1. Some rocks contain useful minerals from which metals like iron, copper and gold can be extracted.
2. Rocks like marble,granite,basalt and sandstone are good building materials.
3. Without minerals ,there would be no cars,trains or planes.
4. We would not be able to clean our teeth or wash our clothes without minerals.
5. Soil is formed from rocks.

Long answers questions

Question. Briefly describe the layers of the earth.
Answer: The earth is divided into three concentric layers---crust,mental and core.Each of these layers have their own characteristics
Crust---
1. The uppermost layer over the earth’s surface is called the crust. It is the famous landscape in which we live consists of rocks, soil and seabed etc.
2. It is not uniformaly thick at all places.
3. It is thinner under the ocean and thicker under the continents.
4. Sial and sima are some constituents of crust.
Mantle---
1. The next layer is the mentle. It extends upto a depth of about 2,900 km.
2. The mantle consists of two layers-the upper mantle and the lower mantle.
3. The average temperature of the upper mantle is 870 degree C.
4. It is found in a semi solid,plastic stage.
5. The lower mantle has an average temperature of 2200 degree C and it is in solid state.
Core---
1. The innermost layer of the earth is called the core.
2. It is about 3,500 km thick.
3. The core is divided into two parts-the inner core and the outer core.
4. The temperature of the outer core is about 5000 degree C.
5. The core is made up of heavy metals like iron and nicle,and is called nife.

Question. What is a rock cycle? Explain with the help of a near labelled diagram.
Answer:
1. The rock cycle is a group of changes.
2. Igneous rock can change into sedimentary rock or into metamorphic rock.
3. Sedimentary rock can change into metamorphic rock or into igneous rock.
4. Metamorphic rock can change into igneous or sedimentary rock.
5. Igneous rock forms when magma cools and makes crystals.
6. The melted minerals can form crystals when they cools down.
7. Igneous rock is formed underground where the magma cools slowly and above ground, when the magma cools quickly.
8. On earth’s surface,wind and water can break Rock into pieces.
9. They can also carry rock pieces to another place.
10. Usually, the rock pieces are deposited in layers.
11. Layers upon layers of fine sediments are collected.
12. After a long time the sediments can be comented together to make sedimentary rock.
13. In this way,igneous rock can become sedimentary rock.

Question. How intrusive and extrusive igneous rocks formed?
Answer: Intrusive rocks—
1. These are formed when cooling of magma take place below the surface of the Earth.
2. Beneath the surface, the molten rocks cools and hardens slowly.
3. The slow cooling allows us large crystals of minerals to form.
4. These rocks are very coarse grained.
Extrusive rocks—
1. These rocks are formed when magma is extruded or forced out,onto the surface of the earth.
2. The magma that reached the surface is known as lava.
3. As the lava cools down and solidifies rapidly on the surface,the minerals present in it form very small crystals.
4. These rocks are very fine grained.

Question. How sedimentary rocks are formed?
Answer:
1. Igneous rocks are exposed to the forces of nature such as wind,water and glaciers.
2. These forces break the rock on the surface of the earth into small pieces.
3. These small pieces of rocks are called sediments.
4. These small pices of rocks or sediments are carried by wind,rivers and glaciers and are deposited on the floors of lakes,seas or oceAnswer:
5. Layers upon layers of fine sendiments are collected.
6. Due to weight of the overlying layer,heat of the interior and chemical reaction, the sediments are compressed,cemented and hardened.
7. The rocks formed in this manner are called sedimentary rocks.

IV. Give reasons—
1. Igeneous are called primary rocks. Because all other rocks are directly or indirectly formed from them.
2. Sedimentary rocks are also called stratified rocks.
Because the deposition take place in layers.
3. Coal and petroleum called fossil fuels.
Because they were formed by the decomposition of remains of prehistoric plants and animals buried under the earth long, long ago.