NCERT Class 7 Social Science Chapter 28 Human Environment Interaction: The Tropical And The Subtropical Region

NCERT Class 7 Social Science Chapter 28 Human Environment Interaction: The Tropical And The Subtropical Region Solutions to each chapter is provided in the list so that you can easily browse through different chapters NCERT Class 7 Social Science Chapter 28 Human Environment Interaction: The Tropical And The Subtropical Region and select need one. NCERT Class 7 Social Science Chapter 28 Human Environment Interaction: The Tropical And The Subtropical Region and After Question Answers Download PDF. NCERT SST Class 7 Solutions.

NCERT Class 7 Social Science Chapter 28 Human Environment Interaction: The Tropical And The Subtropical Region

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Also, you can read the NCERT book online in these sections Solutions by Expert Teachers as per Central Board of Secondary Education (CBSE) Book guidelines. CBSE Class 7 Social Science Solutions are part of All Subject Solutions. Here we have given NCERT Class 7 Social Science Chapter 28 Human Environment Interaction: The Tropical And The Subtropical Region and After, NCERT Class 7 Social Science Textbook of Our Pasts – II: History, Social and Political Life – II: Civics, Our Environment: Geography. for All Chapters, You can practice these here.

Human Environment Interaction: The Tropical And The Subtropical Region

Chapter: 28

Our Environment [Geography]

QUESTIONS WITH ANSWERS

1. Answer the following questions:

Q.1. Name the continent in which Amazon Basin is located.

Ans: It is located in South America. 

Q.2. What are the crops grown by the people of the Amazon Basin?

Ans: Crops such as pineapple, sweet potato and cash crops such as coffee, maize and cocoa are grown by the people Amazon Basin.

Q.3. Name the birds that you are likely to find in the rainforests of the Amazon. 

Ans: Humming birds and Toucans.

Q.4. What are the major cities located on the river Ganga?

Ans: Allahabad, Banaras, Kanpur, Patna, Kolkata and Lucknow are some of the important cities located on the bank of the river Ganga.

Q.5. Where is the one-horned rhinoceros found?

Ans: One-horned rhinoceros are found in Brahmaputra plain.

2. Tick the correct answer:

1. Toucans are a type of

(a) Birds.

(b) Animals.

(c) Crops.

Ans: (a) Birds.

2. Manioc is the staple food of

(a) Ganga Basin. 

(b) Africa.

(c) Amazon.

Ans: (c) Amazon.

3. Kolkata is located on the river

(a) Orange.

(b) Hooghly.

(c) Bhagirathi.

Ans: (b) Hooghly.

4. Deodars and firs are a type of

(a) Coniferous trees.

(b) Deciduous trees.

(c) Shrubs.

Ans: (a) Coniferous trees.

5. Bengal tiger is found in

(a) Mountains.

(b) Delta area.

(c) Amazon.

Ans: (b) Delta area.

3. Match the following:

Ans: 

4. Give reasons:

1. The rainforests are depleting.

Ans: The rainforests are depleting on account of following reasons:

(i) Large scale development activities and setting up of large industries leads to clearing of forests on large scale.

(ii) Floods can submerge them or wash away the top soil.

2. Paddy is grown in the Ganga-Brahmaputra plains.

Ans: For cultivation of paddy, sufficient water is required. The Ganga-Brahmaputra plain fullfils this condition, because they receive high rainfall.

MAP SKILL

1. On an outline map of Indian Sub-continent, draw the river Ganga and Brahmaputra from the source to the mouth. Also show the important tributaries of both the rivers.

Ans: 

2. On the political map of South Africa, draw equator. Mark the countries located on equator.

Ans: 

5. For Fun:

(i) Make a collage to show places of attractions in India. You can divide the class in different groups to show attractions based on mountain landscapes, coastal beaches, wildlife, wildlife sanctuaries and places of historical importance.

Ans. Students do yourself.

6. Activity:

• Collect under mentioned material and observe how destruction of trees effect the soil cover.

Material

(i) Three small flowerpots or food cans (e.g., cold drinks tin cans).

(ii) One big can with holes punched in the bottom (this will act as a sprinkling can).

(iii) Twelve coins or bottle caps.

(iv) Soil.

Process

Take three small cans or pots. Fill them with soil till the top. Press the soil to make it level with the top of the can. Now put four coins or bottle caps on the soil of each can. Take the big can that has been punched with holes and fill it with water. You can also take the sprinkling can from your garden. Now, sprinkle water on the three cans. On the first can sprinkle water very slowly so that no soil splashes out. Let moderate amount of water be sprinkled on the second can. On the third can, sprinkle the water heavily. You will observe that unprotected soil splashes out. Where the ‘rain’ is heavy the amount of soil that splashes out is the maximum and least in case of the first can. The coins or caps represent the tree Covers. lt is clear that if the land is cleared completely of the vegetation, the soil cover will quickly disappear.

Ans: Students do this activity yourself.

SOME OTHER IMPORTANT QUESTIONS FOR EXAMINATION 

Very Short Answer Type Questions

Q.1. Why tropical region is referred to as the equatorial region? 

Ans: The tropical region lies very close to the equator; between 10°N and 10°S. So, it is referred to as the equatorial region. 

Q.2. Which river flows through tropical region?

Ans: The river Amazon flows through tropical region.

Q.3. Define the concept river’s mouth. 

Ans: The place where a river flows into another body of water is called the river’s mouth.

Q.4. What are bromeliads?

Ans: Bromeliads are special plants that store water in their leaves.

Q.5. What do you know about Amazon? Write in two sentences.

Ans: (i) It is the largest river in the world. 

(ii) It contributes 20 per cent of earth’s fresh water.

Q.6. What are tributaries? 

Ans: Tributaries are small rivers that join the main river.

Q.7. How is catchment area of a river forms?

Ans: The main river along with all its tributaries that drain an area forms a river basin or the catchment area.

Q.8. Which river has the largest river basin in the world?

Ans: The Amazon Basin is the largest river basin in the world.

Q.9. How are people causing harm to the rainforests of Amazon? 

Ans: People are clearing the forests to build cities, cultivation of crops or using them for grazing.

Q.10. Name the important species of wildlife found in Ganga basin. 

Ans: Elephants, tigers, deer, monkeys, one-horned rhinoceros is found in the Brahmaputra plains. Bengal tiger, crocodiles and alligators are found in the Ganga basin.

Q.11. Who are known as Amazonian Indians?

Ans: Soil of Amazon is called Amazonian dark earth or Indian black earth.

Q.12. Who are Amazonians?

Ans: The native people of South America. These are original tribes though they had migrates from Asia.

Q.13. Which states lies in the Ganga-Brahmaputra basin?

Ans: The basin lies in the states of Uttrakhand, parts of Haryana, Rajasthan, Madhya Pradesh, Uttar Pradesh, Assam and West Bengal.

Q.14. What type of climatic conditions prevail in Ganga-Brahmaputra basin?

Ans: The basin is dominated by monsoon climate. They bring rains from mid-June to mid-September. The summers are hot and the winters are cool.

Q.15. What is the meaning of population density?

Ans: It means the number of persons that live in one sq. km of area.

Q.16. Why does thick forests grow in the Amazon Basin? 

Ans: As it rains heavily in this region, thick forests grow in the Amazon basin. 

Q.17. What is Maloca?

Ans: Maloca are apartment like houses with a steeply slanting roof.

Q.18. What type of climate is experienced in Ganga-Brahmaputra basin?

Ans: Ganga-Brahmaputra basin experiences monsoon climate.

Q.19. Which is the only mode of transport in the interiors of Amazon basin and why?

Ans: Waterways are the only modes of transport in the interiors of the Amazon. This is because the dense forests and swampy grounds are hindrances in building road and rail networks.

Q.20. What is the staple food of the people living in the Amazon Basin and Ganga Brahmaputra?

Ans: The staple food of the people living in the Amazon basin is manioc, also known as cassava, while paddy is the main staple food of the people living in the Ganga-Brahmaputra basin. 

Q.21. Why do less number of people live in the Ganga-Brahmaputra basin?

Ans: Less number of people live in the Ganga- Brahmaputra basin because the mountain area with steep slopes have in hospitable terrain.

Short Answer Type Questions

Q.1. Describe the location of Amazon Basin. 

Ans: Amazon Basin situated between 10° N and 10° S. It originates from the Andes Mountain in Peru and drains into the Atlantic Ocean. The river Amazon along with its tributaries forms the largest river basin in the world. This basin covers a major part of Brazil and some parts of Peru, Ecuador, Colambia, Bolivia and Venezuela.

Q.2. How will you describe the climatic condition of Amazon Basin?

Ans: (i) The climatic condition of Amazon Basin is best described as Hot-Wet Equatorial Climate. 

(ii) This type of climate is characterised by high temperature that prevails throughout the year. 

(iii) There is very little variation in the day and night temperatures. At night, temperatures go down while humidity remains the same.

(iv) The high humidity and heat throughout the year makes this region almost unbearable to live in.

Q.3. Ecologically Amazon basin is very important. Why? 

Ans: Ecologically Amazon basin is very important as:

1. It has world’s extensive belt of rainforests with rich biodiversity. 

2. It is near to the equator and is important to control the carbon dioxide level in the atmosphere.

Q.4. Differ the varieties of fishes in Amazon basin and the Ganga-Brahmaputra Basin. 

Ans: Amazon Basin: Several species of fishes including the flesh eating Piranha fish is founded in the river.

Ganga-Brahmaputra Basin: The most popular varieties of the fish are rohu, catla and hilsa. It is also the staple diet of the people living in that area.

Q.5. Write a brief note on the flora and fauna found in Amazon Basin. 

Ans: The flora and fauna in the rainforest of Amazon basin include various parasitic plants like orchids and bromeliads; animals like the jaguar, birds like toucans, and huge snakes like the anaconda and boa constrictor. Thousands of species of birds, reptiles and insects are also found here.

Q.6. Describe the formation of the Ganga-Brahmaputra plain.

Ans: Ganga-Brahmaputra has been formed by three rivers-the Indus, the Ganga and the Brahmaputra and their tributaries. Because of absence of relief features, meanders, ox bow lakes and deltas have been formed by the river.

Q.7. The Ganga basin offers a lot of tourist activities. Cite some examples for the above statement.

Ans: 1. Taj Mahal on the banks of River Yamuna in Agra.

2. Allahabad. 

3. Bhakthist stupas in Uttar Pradesh and Bihar.

4. Lucknow with its Imambara. 

5. Kaziranga and Manas wildlife sanctuaries in Assam.

6. Tribal culture of Arunachal Pradesh.

Q.8. Write in brief about the Ganga-Brahmaputra plain. 

Ans: The Ganga-Brahmaputra river system together form the largest part of the Great Plains of the north India. Both the rivers flow parallel on either side of the Himalayas. The Brahmaputra river join Ganga in Bangladesh and together they form the easternmost part of the basin.

Q.9. Describe in short about the location of the Ganga-Brahmaputra plain. 

Ans: The Ganga-Brahmaputra region lies between 25°N and 30°N. The composite Ganga-Brahmaputra-Meghna Basin lies in Tibet, Nepal, India and Bangladesh and extends to an area of 10,86,000 sq km.

Q.10. What types of crops were grown in the Ganga-Brahmaputra region? 

Ans: (i) Wheat, maize, sorghum, gram and millets are the crops that are grown. 

(ii) Cash crops like sugarcane and jute are also grown. Banana plantations are seen in some areas of the plain.

(iii) In West Bengal and Assam tea is grown in plantations. 

(iv) Silk is produced through the cultivation of silk worms in parts of Bihar and Assam.

(v) In the mountains and hills, where the slopes are gentle, crops are grown on terraces.

Q.11. Describe in short about the wildlife of the Ganga-Brahmaputra basin.

Ans: (i) There is a variety of wildlife in the basin. Elephants, tigers, deer and monkeys are common here.

(ii) The one-horned rhinoceros is found in the Brahmaputra plain.

(iii) In the delta area, Bengal tiger, crocodiles and alligators are found.

(iv) Aquatic life abounds in the fresh river waters, the lakes and the Bay of Bengal sea.

Q.12. Name some developmental activities that have changed the life of the people living in the Amazon Basin in recent years. 

Ans: Developmental activities that have changed the life of the people living in the Amazon basin are:

(a) In 1970 the Trans Amazon highway made all parts of the rain forest accessible.

(b) Aircrafts and helicopters are also used for reaching various places.

(c) The indigenous population was pushed out from the area and forced to settle in new areas where they continued to practise their distinctive ways of farming. 

Q.13. What is a impact of the developmental activities in the Amazon basin? 

Ans: The developmental a activities are leading to the gradual destruction of the biologically diverse rainforests. The topsoil is washed away as the rains fall and the lush forest turn into a barren landscape.

Q.14. Name the countries drained by the Amazon Basin. 

Ans: Amazon basin drains portions of Brazil, parts of Peru, Bolivia, Ecuador, Columbia and a small part of Venezuela.

Q.15. Why is plant growth very dense in the Amazon basin?

Ans: Plant growth is very dense in the Amazon basin because of heavy rainfall and dense foliage.

Q.16. Name the rivers that drain Ganga-Brahmaputra basin. 

Ans: The tributaries of the river Ganga like the Ghagra, Son, Chambal, Gandok, Kosi and the tributaries of Brahmaputra drain the Ganga-Brahmaputra Basin.

Q.17. “The topography of the Ganga-Brahmaputra Basin is varied.” Discuss. 

Ans: The topography of the Ganga-Brahmaputra is varied. While certain areas are mountainous, the majority of area is a plain. The mountains are steep and inhospitable but the plains are fertile and support dense population.

Q.18. What is slash and burn agriculture?

Ans: Slash and Burn is a way of cultivating land where farmers clear a piece of land by slashing or cutting down trees and bushes. These are then burnt, which releases the nutrients into the soil. After repeatedly using the patch of land, the soil looses its nutrients. So it is abandoned. The they clear another plot of land to plant. In the mean time young trees grow in the old field. In this way soil fertility is restored. People can then return to it and start cultivating it again.

Long Answer Type Questions

Q.1. Give an account of cities and towns settled along the Ganga river. 

Ans: The plains of river Ganga and Brahmaputra serves as a breeding ground for the emergence of several big towns and cities. The cities of Allahabad, Kanpur, Varanasi, Lucknow, Patna and Kolkata all with the population of more than ten lakhs are located along the river Ganga. Kolkata is an important port on the river Hoogly. The cities are well connected with each other by the means of roads and railways. 

Q.2. What do know about the Ganga-Brahmaputra basin?

Ans: The Ganga-Brahmaputra Basin is one of the most fertile regions of the world. The shifting agriculture in India, called Jhooming, is practised in some North- Eastern States on hilly slopes. But farmers in the Ganga-Brahmaputra Basin commonly practise intensive agriculture. Many farmers now use tractors and other modern farm equipments. Due to the many favourable factors, the Ganga-Brahmaputra Basin is highly industrialised. Cities like Delhi, Lucknow, Agra, Allahabad, Patna, Kolkata, Guwahati, etc., are situated in this basin. Delhi is the capital of India. Allahabad lies at the confluence of the two rivers-Ganga and Yamuna.

Q.3. What is the vegetation cover in Ganga- Brahmaputra plain?

Ans: Crops: Wheat, maize, sorghum, gram and millets are the crops that are grown. Cash crops like sugarcane and jute are also grown. Banana plantations are seen in some areas of the plain. Tea is grown in plantations. Silk is produced through cultivation of silkworm. In the mountains and hills, it is done on terraces.

Forests: In the Ganga and Brahmaputra plain, tropical deciduous trees grow along with teak, sal and peepal. Thick bamboo groves are common in the Brahmaputra plain. The delta area is covered with the mangrove forests. In some parts, coniferous trees like pine, deodar and fir can be seen.

Q.4. Explain the forest and wildlife of Amazonia basin. Why is it called the earth’s richest biomes?

Ans: Amazonia, is the world’s largest vegetation zone characterised by dense vegetation and varied animal life and covers more than half of Brazil. Tropical rainforests grow only near the equator. These rainforests are the richest of all environments, in terms of plant and animal life. The rainforest trees are characterised by layering arrangement or like storeys of a skyscraper, called canopy.

The flora and fauna in the rainforest include various parasitic plants like orchids and bromeliads; animals like the jaguar, birds like toucans, and huge snakes like the anaconda and boa constrictor. Thousands of species of birds, reptiles and insects are found here. It is thus one of the earth’s richest biomes (a large community of flora and fauna), with a staggering diversity of life forms.

Q.5. Explain the features rainforests of the Amazon basin. 

Ans: Rainforests of the Amazon basin have the following features:

(a) As it rains heairly in this region, thick forests grow.

(b) The forests are in fact so thick that the dense roof created by the leaves and branches does not allow the sunlight to reach the ground.

(c) Only shade tolerant vegetation may grow here.

(d) Orchids, bromeliads grow as plant parasites.

Q.6. Explain the lifestyle of the people living in the Amazon Basin.

Ans: The lifestyle of the people living in the Amazon basin can be explained as follows:

(a) People grow most of their food in small areas after clearing some trees in the forests.

(b) While men hunt and fish along the rivers, women take care of the crops. They mainly grow tapioca, pineapple and sweet potato. 

(c) As hunting and fishing are uncertain, it is the women who keep their families alive by feeding them the vegetables they grow. They practise slash and burn agriculture.

Q.7. Give an account of the industrial development of the Ganga-Brahmaputra plain.

Ans: Industrial development of the Ganga-Brahmaputra plain can be explained as follow:

(a) The Ganga-Brahmaputra plain has several big towns and cities. 

(b) The cities of Allahabad, Kanpur, Varanasi, Lucknow, Patna and Kolkata all with the population of more than 10 lakhs are located along the river Ganga. 

(c) All the four ways of transport are well developed in the Ganga-Brahmaputra basin.

(d) In the plain the roadways and railways transport people from one place to another.

(e) The waterways is an effective means of transport particularly along the rivers. 

(f) The plain area also has a large number of airports.

Higher Order Thinking Skill

Q.1. What are the difficulties in utilising the rainforests for commercial purpose?

Ans: (i) These forests are very dense, wet and swampy and cannot be cleared easily. Hence construction of roads and railways is difficult.

(ii) The wood of the trees found here is hard. The logs cannot be easily floated down rivers. 

(iii) Although these forests yield high quality timber, the hard wood trees are also expensive to cut.

(iv) Trees do not grow in social stant. This means that while a sq km of a temperate forest might have 25 or fewer species of trees, an area of the same size in the rainforest may have as many as thousand tree species. To find the same species of tree, one would have to travel over a large area.

Q.2. What is the extent of the Amazon Basin?

Ans: The extent of the Amazon Basin is between 10°N and 10°S, which is also known as the equational region. The river Amazon flows through this region. It flows from the mountains to the west and reaches the Atlantic Ocean to the east.

Q.3. How does environment plays an important role in the distribution of the population in the Ganga-Brahmaputra basin?

Ans: The environment plays a dominant role in the distribution of the population. The mountain areas with steep slopes have inhospitable terrain. Therefore less number of people live in the mountain area of the Ganga-Brahmaputra basin. The plain area provides the most suitable land for human habitation.

Value Based Questions

Q.1. “The life of people of the Amazon is slowly changing.” Explain how.

Ans: Life of the people of the Amazon basin  is slowly changing. In the older days the heart of the forest, could be reached only by navigating the river. In 1970 the Trans-Amazon Highway made all parts of the rainforest accessible. Aircrafts and helicopters are also used for reaching various places. The indigenous population was pushed out from the area and forced to settle in new areas where they continued to practise their distinctive way of farming. The developmental activities are leading to the gradual destruction of the biologically diverse rainforests. It is estimated that a large area of the rainforest has been disappearing annually in the Amazon basin.

Q.2. How has the environment played a significant role in the discussion of the population?

Ans: The mountain areas with steep slopes have inhospitable terrain. Therefore, less number of people live in the mountain area of the Ganga-Brahmaputra Basin. The plain area provides the most suitable land for human habitation. The soil is fertile. The density of the population of the people is very high.

OBJECTIVE TYPE QUESTIONS

1. Multiple Choice Questions:

Choose the correct option: 

1. The Amazon basin extends between ______.

(a) 0° to 10°N.

(b) 10°N to 10°S.

(c) 5°N to 10°S.

(d) 5°N to 15°S. 

Ans: (b) 10°N to 10°S.

2. The source of the Amazon River lies in Andes of _______.

(a) Peru.

(b) Ecuador. 

(c) Brazil.

(d) Bolivia.

Ans: (a) Peru.

III. Match the following:

Ans: 

lll. Give the answer of the following in one word or in one sentence:

(i) The number of persons that live in one sq km of area.

Ans: Population density.

(ii) Slash and burn agriculture.

Ans: Shifting cultivation.

(iii) Large apartment like houses with steeply slanting roofs.

Ans: Maloca.

(iv) Single river system which drains an area.

Ans: River Basin.

(v) Small rivers that join the main river.

Ans: Tributaries.