Bhagya

Std 8 Geography Chapter 4 Questions And Answers Structure of Ocean Floor Maharashtra Board

February 6, 2025January 4, 2025 by Bhagya

Balbharti Maharashtra State Board Class 8 Geography Solutions Chapter 4 Structure of Ocean Floor Notes, Textbook Exercise Important Questions and Answers.

Class 8 Geography Chapter 4 Structure of Ocean Floor Questions And Answers Maharashtra Board

Structure of Ocean Floor Class 8 Questions And Answers Chapter 4 Maharashtra Board

Class 8 Geography Chapter 4 Structure of Ocean Floor Textbook Questions and Answers

1. Choose the correct option:

Question a.
Like there are landforms on land, ocean floor also has submerged landforms because ………….
(i) there is land under water
(ii) there are volcanoes under water
(iii) land is continuous and there is water in deeper parts
(iv) though land is continuous, its level is not the same everywhere like that of water
Answer:
(iv) though land is continuous, its level is not the same everywhere like that of water

Question b.
Which part of the ocean floor is most useful to the man?
(i) Continental shelf
(ii) Continental slope
(iii) Abyssal plains
(iv) Marine deeps
Answer:
(i) Continental shelf

Question c.
Which one of the following option is related to marine deposits?
(i) Rivers, glaciers, continental shelf, remains of plants and animals
(ii) Volcanic ash, continental shelf, remains of plants and animals
(iii) Volcanic ash, lava, fine particles of soil
(iv) Volcanic ash, remains of plants and animals, abyssal plants
Answer:
(iii) Volcanic ash, lava, fine particles of soil

2. Question a.
Name the landforms shown in the following figure.
(Note: The answer is given directly.)
Maharashtra Board Class 8 Geography Solutions Chapter 4 Structure of Ocean Floor 2.2
Answer:

Question b.
Which of these landforms are useful for deep sea research?
Answer:
Submarine plateau and marine trench are the landforms useful for deep sea research.

Question c.
Which of these are appropriate to be used for the protection of marine borders and naval base building?
Answer:
Continental shelf is appropriate to be used for the protection of marine borders and naval base building.

3. Give geographical reasons:

Question a.
The study of ocean floor is useful to man.
Answer:

Various minerals, rocks, fine I soil particles are found on the sea floor.
Remains of marine plants and animals are also found on the ocean floor.
To study the marine life, mineral wealth as well as the process of volcanic eruption, the study of ocean floor is useful to man. ‘

Question b.
The continental shelf is a paradise for fishing activity.
Answer:

Being a shallowest part of the ocean bed, sunlight reaches up to continental shelf easily.
As its effect, algae, plankton, etc. grows on a large scale on continental shelf.
Algae, plankton, etc. is food for fish. Therefore, fish are found on a large scale on continental shelf. Therefore, the continental shelf is paradise for fishing activity.

Question c.
Some marine islands are actually the peaks of sea mountains.
Answer:

The hundreds of kilometres wide and thousands of kilometres long hills found on the ocean bed are called submerged hills.
Peaks of some of the submerged hills come above the sea level.
These peaks are the visible land areas surrounded from all sides by water. These peaks are called islands. Thus, some marine islands are actually the peaks of sea mountains.

Question d.
The continental slope is considered to be the boundary of continents.
Answer:

Continental slope lies beyond the continental shelf.
The deep abyssal plain begins beyond the continental slope. Therefore, the continental slope is considered to be the boundary of continents.

Question e.
The disposal of waste materials in the oceans by man is harmful to the 1 environment.
Answer:

The disposal of waste materials in the oceans by man increases the pollution of sea water.
This disposed waste materials harm the life of marine animal life and marine plant. Thus, the disposal of waste materials in the oceans by man is harmful to the environment.

4. Observe the map on Pg 27 in ‘Give it a try’ and answer the following questions:

Question a.
Madagascar and Sri Lanka are related to which landform of the ocean floor?
Answer:
Madagascar and Sri Lanka are related to island of the ocean floor.

Question b.
Near which continent are these landforms located?
Answer:
Madagascar is located near the continent of Africa and Sri Lanka is located near the continent of Asia.

Question c.
Which islands in our country are examples of peaks of submerged mountains?
Answer:
Andaman and Nicobar islands in our country are examples of peaks of submerged mountains.

Activity:

Question a.
prepare a model of the ocean floor.
Answer:
Maharashtra Board Class 8 Geography Solutions Chapter 4 Structure of Ocean Floor 4

1. While studying the ocean floor, we must keep in mind the age of the ocean bed. By studying the deposits on the ocean bed, it occurred to the scientists that the deposits at the ocean floor are not older than 200 million years.

2. The maximum age of the rocks on the continents is supposed to be 3200 million years. Then where have the deposits on the sea bed which are older than 200 million years gone? This made the scientists restless. Then they started the study of the rocks along with the deposits.

3. This made them realize that the rocks are also not older than 200 million years. It was inferred that the ocean floor is very young as compared to the earth’s surface. Now this is unanimously accepted. This research was then used in the study of the concept of plate tectonics.

Class 8 Geography Chapter 4 Structure of Ocean Floor Additional Important Questions and Answers

Choose the correct answer and complete the sentences:

Question a.
Continental slope has slope.
(a) flatter
(b) broader
(c) steeper
(d) lower
Answer:
(c) steeper

Question b.
The average depth of the oceans is around metres.
(a) 7300
(b) 3700
(c) 3900
(d) 3300
Answer:
(b) 3700

Examine the following statements and correct the incorrect ones:

Question a.
Abyssal plain lies beyond the continental shelf.
Answer:
Incorrect.
Correct statement: Abyssal plain lies beyond the continental slope.

Question b.
Around 51 per cent of the surface of the earth is covered by water.
Answer:
Incorrect.
Correct statement: Around 71 per cent of the surface of the earth is covered by water.

Question c.
Natural gas and mineral oil can be obtained from the continental shelf.
Answer:
Correct.

Question d.
For survey purpose in India, the height of sea level at Kanyakumari is considered to be zero.
Answer:
Incorrect.
Correct statement: For survey purpose in India, the height of sea level at Chennai is considered to be zero.

Question e.
Active volcanoes are mostly seen in marine trenches.
Answer:
Correct.

Answer the following questions in one sentence each:

Question a.
What is called continental shelf?
Answer:
The land near the coast and submerged under the sea is called continental shelf.

Question b.
What is called continental slope?
Answer:
The steeper slope of the sea bed beyond the extent of continental shelf is called continental slope.

Question c.
What is called abyssal plain?
Answer:
The flat part of the sea bed that lies
beyond the continental slope is called abyssal plain.

Question d.
What is called submerged hills?
Answer:
The hundreds of kilometres wide and thousands of kilometres long hills found on the ocean bed are called submerged hills.

Question e.
What is called marine islands?
Answer:
Peaks of some of the submerged hills that come above the sea level are called marine islands.

Question f.
What is called submarine plateau?
Answer:
The flat and extensive summit of marine island is called submarine plateau.

Question g.
What is called marine deep?
Answer:
The landforms on the ocean bed that are comparatively less extending and shallower ones are called marine deep.

Question h.
What is called marine trench?
Answer:
The landforms on the ocean bed that are comparatively more extending and deeper ones are called marine trench.

Match the columns and complete the chain:

Question a.

‘A’ Column	‘B’ Column	‘C’ Column
1. Andaman – Nicobar	(i) Submarine plateau	(a) Pacific Ocean
2. Chagos	(ii) Located on continental shelf	(b) Bay of Bengal
3. Mariana	(iii) Islands	(c) Arabian Sea
4. Mumbai High	(iv) Marine deep	(d) Indian Ocean

Answer:

‘A’ Column	‘B’ Column	‘C’ Column
1. Andaman – Nicobar	(iii) Islands	(b) Bay of Bengal
2. Chagos	(i) Submarine plateau	(d) Indian Ocean
3. Mariana	(iv) Marine deep	(a) Pacific Ocean
4. Mumbai High	(ii) Located on continental shelf	(c) Arabian Sea

Answer the following questions in brief:

Question a.
What is marine deposits?
Answer:

Marine deposit is a type of marine deposition.
The rivers and glaciers flowing from the continent bring pebbles, clay, soil, etc. with them when they meet sea or ocean.
These materials get deposited on the continental shelf. The deposits are known as marine deposits.
Due to pressure of sea water and deposition of layers over layers of sediments, sedimentary rocks are formed.
Marine life and the availability of minerals in the sea bed can be studied with the help of marine deposits.

Question b.
What is marine oozes?
Answer:

Marine oozes is a type of marine deposit.
Lava and ash erupting out of volcano, fine soil particles, remains of plants and animals, etc. get deposited on marine abyssal plains. Deposits of these materials on the abyssal plains are known as marine oozes.
Marine oozes are in the form of fine clay. The percentage of remains of plants and animals in marine oozes is up to 30 per cent.
Marine oozes are also useful to study marine life and the availability of minerals in the sea bed.

Question c.
Write in brief about the continental shelf.
Answer:
1. The land near the seacoast and submerged under the sea is called continental shelf. The depth of continental shelf is about 200 metres below the sea level.

2. Continental shelf is found to be narrow along the coasts of some continents and broad along the coasts of some other continents.

3. Being a shallowest part of the ocean bed, sunlight reaches up to continental shelf easily. As its effect, the food for fish like algae, plankton, etc. grows on a large scale on continental shelf. Therefore, continental shelf is useful for fishing occupation.

4. Various minerals, natural gas and mineral oil, etc. can also be obtained from mining the continental shelf. For example, Mumbai High located on the continental shelf of the Arabian Sea is a source from where the mineral oil and natural gas is obtained.

Question d.
Write in brief about the continental slope.
Answer:

The steep slope of the sea bed beyond the extent of continental shelf is called continental slope.
The depth of the continental slope is from 200 metres to 3600 metres below the sea level.
The continental slope is found to be comparatively narrower.
The lower boundary of the continental slope is considered as the boundary of I continent.

Question f.
Write in brief about the abyssal plains.
Answer:

The flat part of the sea bed that lies beyond the continental slope is called abyssal plains.
Various submerged landforms like
submerged hills, submerged mountains, etc. are seen on abyssal plains.
Submarine plateaus are also found on the abyssal plains.

Question g.
Write in brief about mean sea level.
Answer:

The average of the highest high tide and the lowest low tide is considered to calculate the mean sea level.
This average is considered to be zero sea level.
The altitude of any place above the sea level is measured and expressed in positive value. (For example, Mount Everest is 8848 metres high.)
The depth of any place below the sea level is measured and expressed in negative value. (For example, Mariana Trench is 11034 metres below sea level.)

Study the following map/figure/graph and answer the following questions:

Can you tell?

Maharashtra Board Class 8 Geography Solutions Chapter 4 Structure of Ocean Floor 3

Question a.
What parameters were used for classifying the landforms on the earth?
Answer:
Altitude and the shape of the land were the parameters used for classifying the landforms on the earth.

Question b.
What parameters were used for naming the landforms below water?
Answer:
Depth from the seafloor and the shape of the land were the parameters used for naming the landforms below water.

Give it a try.

Question a.
Name the submerged landforms shown in the diagram.
(Note: The answer is given directly.)
Maharashtra Board Class 8 Geography Solutions Chapter 4 Structure of Ocean Floor 5
Answer:

Question b.
Identify the ocean shown in the map of the ocean floor.
Answer:
The ocean shown in the map of the ocean floor is Indian Ocean.

Question c.
Which region would be ideal for fishing and why?
Answer:
The region near Madagascar island would be ideal for fishing. Madagascar island has a shallow continental shelf. The warm stream and cold stream also meet near Madagascar island. Therefore, the region near Madagascar island would be ideal for fishing.

2. Name the landforms shown in the following figure and answer the following questions:
(Note: The answer is given directly.)

Question a.
Maharashtra Board Class 8 Geography Solutions Chapter 4 Structure of Ocean Floor 1
Answer:

Thought-Provoking Questions

Think about it.

Question a.
If the classification of landforms on land can be done on the basis of altitude and size, then how can the landforms submerged underwater are classified?
Answer:
If the classification of landforms on land can be done on the basis of altitude and size, then the landforms submerged underwater are classified on the basis of the depth from the seafloor and the shape of the land there.

Use your brainpower!

Do this activity when you go to the seashore with your parents or teachers. Observe the materials which have come with the waves. Classify them as per the flowchart given below:
Maharashtra Board Class 8 Geography Solutions Chapter 4 Structure of Ocean Floor 8

Question a.
Which of these are perishable items?
Answer:
Plants, conches and shells, aquatic animals of these are perishable items.

Question b.
Which are non-perishable?
Answer:
Chemicals, metals and plastic/glass are non-perishable.

Question c.
What will happen because of perishable items?
Answer:
Perishable items will not create pollution of seacoast and seawater on a large scale. The remains of perishable items will get deposited in the form of marine oozes on the ocean bed.

Question d.
What will happen because of non-perishable items?
Answer:
Non-perishable items will create pollution of seacoast and seawater on a large scale.

Question f.
Suggest measures to control deposition of non-perishable items on the coast.
Answer:
The following measures can be taken to control deposition of non-perishable items on the coast:

Plastic bags, plastic or glass containers must be prohibited on the seacoasts.
Strict action must be taken against offenders carrying the banned products on the seacoasts.
Hoardings explaining the importance of clean seacoasts must be displayed on all the seacoast.

Question g.
How will you run a campaign of environmental conservation to keep the coasts clean?
Answer:
We will run a campaign of environmental conservation to keep the coasts clean as follows:

We will display hoardings explaining the importance of clean seacoasts on the seacoasts.
We will arrange street plays, dramas, etc. highlighting the importance of clean seacoasts.
We will arrange special programmes during the festivals like Ganeshotsav, Diwali, Christmas, etc. to keep the seacoasts clean.

Open-Ended Questions:

Question a.
Suggest measures to control deposition of non-perishable items on the coast.
Answer:
The following measures can be taken to control deposition of non-perishable items on the coast:

Plastic bags, plastic or glass containers must be prohibited on the seacoasts.
Strict action must be taken against offenders carrying the banned products on the seacoasts.
Hoardings explaining the importance of clean seacoasts must be displayed on all the seacoasts.

Question b.
How will you run a campaign of environmental conservation to keep the coasts clean?
Answer:
We will run a campaign of environmental conservation to keep the coasts clean as follows:

We will display hoardings explaining the importance of clean seacoasts on the seacoasts.
We will arrange street plays, dramas, etc. highlighting the importance of clean seacoasts.
We will arrange special programmes during the festivals like Ganeshotsav, Diwali, Christmas, etc. to keep the seacoasts clean.

8th Std Geography Questions And Answers:

Std 9 History Chapter 1 Question Answer Maharashtra Board

February 6, 2025January 4, 2025 by Bhagya

Balbharti Maharashtra State Board Class 9 History Solutions Chapter 1 Sources of History Notes, Textbook Exercise Important Questions and Answers.

Sources of History Class 9 Questions And Answers Maharashtra Board

Class 9 History Chapter 1 Sources of History Questions And Answers Maharashtra Board

History Class 9 Chapter 1 Question Answer Maharashtra Board

1. A Choose the right option and rewrite the sentence.

Class 9 History Chapter 1 Sources Of History Questions And Answers Question 1.
The National Archives of India is situated at ______.
(a) Pune
(b) New Delhi
(c) Kolkata
(d) Hyderabad
Answer:
(b) New Delhi

Sources of History Class 9 History Chapter 1 Question 2.
The _______ is included among the Audio -Visual media.
(a) Newspaper
(b) Television
(c) All India Radio
(d) Periodicals
Answer:
(b) Television

Question 3.
______ is not included in physical sources.
(a) Coins
(b) Ornaments
(c) Buildings
(d) Proverbs
Answer:
(d) Proverbs

B. Identify the wrong pair and rewrite the corrected one:

Question 1.
(1) Jal Cooper – Philatelist
(2) Kusumagraj – Poet
(3) Anna Bhau Sathe – People’s bard
(4) Amar Shaikh – Art Collector
Answer:
Amar Shaikh – Art Collector

2. Write Short Notes:

Question 1.
Written Sources
Answer:
(i) Any historical document written by hand or typed or in printed form is called written sources.
(ii) The following are included in written sources: Newspapers, Periodicals, Diaries, Reference books, Correspondence, Document in the Archives, Government Gazettes, Postage Stamps, and Encyclopedias.

Question 2.
Press Trust of India (PTI)
Answer:
(i) After 1953, the Press Trust of India has been an important source of primary details of all important events and of articles on important subjects.

(ii) Press Trust of India has provided reports, photographs and articles on financial and scientific issues to newspapers. PTI has now started its online service.

(iii) During the 1990s, PTI started using the ‘satellite broadcast’ technology instead of teleprinters to send news all over the country.

(iv) This material is important for writing the history of modern India.

3. Give reasons:

Question 1.
The postal department tries to preserve the heritage and integrity of Indian culture through postage stamps.
Answer:
(i) Postage stamps reveal a lot to us about changing times due to the variety in the sizes of the stamps, the novelty in their subjects and colour schemes.

(ii) The Postal Department issues postage stamps on a wide variety of themes.

(iii) It issues stamps on political leaders, flowers, animals, birds, an event, or the silver, golden, diamond jubilees or centenary, bicentenary and tercentenary of different events.

(iv) It is therefore, a valuable repository of history.

(v) Thus the postal department tries to preserve the heritage and integrity of Indian culture through postage stamps.

Question 2.
Audio-visual media are an important source for writing the history of modem India.
Answer:
(i) Audio-visual means possessing sound and visual content; for example, films and television

(ii) We have channels like History channel and Discovery channel which telecast footage of historical events in multimedia.

(iii) With the help of satellites, live coverage of all political, social and cultural events is possible across the globe. This helps to create an accountable repository for future reference as well.

(iv) Video libraries possess a vast storage of historical information in audio-visual mode which becomes handy in writing the history of modem India.

Class 9 History Chapter 1 Sources of History Additional Important Questions and Answers

Choose the correct option from the given options and rewrite the statements:

Question 1.
Information and Broadcasting Department published ______, an annual reference book.
(a) India 2000
(b) Incredible India
(c) Indian Horizon
(d) Aspiring India
Answer:
(a) India 2000

Question 2.
The place where historical documents are _______.
preserved is called
(a) Library
(b) Store Room
(c) Archives
(d) History Room
Answer:
(c) Archives

Question 3.
Newspapers are considered the _______ pillar of democracy.
(a) First
(b) Second
(c) Third
(d) Fourth
Answer:
(d) Fourth

Question 4.
_____ has also produced various documentaries on prominent social leaders, on people who have made major contributions and about important locations in India.
(a) British Broadcasting Corporation (BBC)
(b) Reuters
(c) Indian News Review
(d) Bloomberg
Answer:
(c) Indian News Review

Question 5.
Aavahan is written on the backdrop of Sino- Indian war by the noted Marathi poet _____.
(a) Narayan Gupte
(b) Kusumagraj
(c) G.D. Madgulkar
(d) Namdeo Dhasal
Answer:
(b) Kusumagraj

Question 6.
Cooper edited _______.
(a) India’s Stamp Journal
(b) Indian Philatelic Magazine
(c) Stamp Synopsis
(d) The Journal of Philatelic Bureau
Answer:
(a) India’s Stamp Journal

Question 7.
After 1953, the ____ has been an important source of primary details of all important events.
(a) Union Trust of India
(b) Press Trust of India
(c) Information and Broadcasting Ministry
(d) Film and Television Institute of India
Answer:
(b) Press Trust of India

Question 8.
Duringthe 1990s, PTI started using ____ technology instead of Teleprinters.
(a) GPS Device
(b) Ultrasonic Gadget
(c) Radio Programming
(d) Satellite Broadcast
Answer:
(d) Satellite Broadcast

Question 9.
The Government of India started the Film and Television Institute of India at Pune in 1960 with the purpose of providing _______.
(a) Entertainment
(b) Public Education
(c) International updates
(d) Intra-societal information
Answer:
(b) Public Education

Question 10.
The Indian government issued the ______ stamp in 1977.
(a) Narsee Monjee
(b) Jal Cooper
(c) Birsa Munda
(d) Senapati Bapat
Answer:
(b) Jal Cooper

Question 11.
The Chhatrapati Shivaji Maharaj Museum is at ________.
(a) Delhi
(b) Mumbai
(c) Kolkata
(d) Chennai
Answer:
(b) Mumbai

Question 12.
The ______ issues postage stamps on a wide variety of themes.
(a) Publications Division
(b) Postal Department
(c) Income Tax Department
(d) Revenue Department
Answer:
(b) Postal Department

Question 13.
______ prints the notes.
(a) Reserve Bank of India
(b) Union Bank of India
(c) Philatelic Bureau of India
(d) State Bank of India
Answer:
(a) Reserve Bank of India

Question 14.
Empire of India Philatelic Society was founded by ______.
(a) Pherozeshah Mehta
(b) Mahzarin Banaji
(c) Jal Cooper
(d) Dinshaw Patel
Answer:
(c) Jal Cooper

Question 15.
PTI has provided reports, photographs and articles on ___ issues to newspapers.
(a) Therapeutic
(b) Financial and scientific
(c) Demographic and Topographic
(d) Environmental
Answer:
(b) Financial and scientific

Identify and write the wrong pair in the following sets:

Question 1.
(1) Powada – Oral sources
(2) Documentaries – Audio Visual Sources
(3) Coins – Material Sources
(4) Owis – Archaeological Sources
Answer:
Owis – Archaeological Sources

Question 2.
(1) India 2000 – Annual Reference book
(2) Indian News Review – News reels and documentariess.
(3) FTII – Radio Programmes
(4) Reserve Bank of India – Printing notes
Answer:
FTII – Radio Programmes

Question 3.
(1) Chhatrapati Shivaji Maharaj Museum – Mumbai
(2) Reserve Bank Museum – Pune
(3) National Archives of India – Calcutta
(4) Film and Television Institute of India – Pune
Answer:
National Archives of India – Calcutta

Do as directed.
Complete the concept map:

Question 1.
Answer:
Maharashtra Board Class 9 History Solutions Chapter 1 Sources of History 1

Question 2.
Answer:
Maharashtra Board Class 9 History Solutions Chapter 1 Sources of History 2

Question 3.
Answer:
Maharashtra Board Class 9 History Solutions Chapter 1 Sources of History 3

Question 4.
Answer:
Maharashtra Board Class 9 History Solutions Chapter 1 Sources of History 4

Write short notes:

Question 1.
Coins
Answer:
(i) We can also understand history with the help of coins and the changes in the printing of currency notes.
(ii) The Reserve Bank of India prints the notes. It has its headquarters in Mumbai.
(iii) The coins from 1950 to those used at present, the metals used for making them, their different shapes, and the diversity of subjects on them together help us to understand the important contemporary issues in India; For example coins to convey the message of population control and coins communicating the importance of agriculture and of farmers.

Question 2.
Jal Cooper
Ans
(i) The Indian government issued the ‘Jal Cooper’ stamp in 1977. Jal Cooper was an internationally acclaimed philatelist, i.e. an expert on the subject of ‘postage stamps’.
(ii) Bom in a Parsi household in Mumbai, Cooper edited ‘India’s Stamp Journal’.
(iii) He was the founder of the first Philatelic Bureau in India, an office that collected stamps. He founded the ‘Empire of India Philatelic Society.
(iv) He went on to write many books on this subject. He gave a scientific bent to his hobby.
(v) He played a pivotal role in taking the study of Indian postage stamps to the international level.
(vi) Having started his career as a postage stamp collector, Cooper achieved the expertise of a philatelist at the international level.
(vii) The postage stamp on Jal Cooper is an important source to understand his significant contribution to this field.

Explain the statements with reason:

Question 1.
Museums reflect the unique heritage of a state.
Answer:
(i) All states of India have museums that depict the characteristics and display the cultural and social heritage of the state.
(ii) They enable us to understand history; For example, the Chhatrapati Shivaji Maharaj Museum at Mumbai and the Reserve Bank Museum in Pune city.
(iii) Apart from the Government Museums, some private collectors also set up their own museums.
(iv) They are based on distinctive subjects; For example, coins, notes, lamps and nutcrackers in different shapes, cricket equipment, etc.

Read the passage and answer the questions.

The Indian government issued the ‘Jal Cooper’ stamp in 1977. Jal Cooper was an internationally acclaimed philatelist, i.e. an expert on the subject of ‘postage , stamps’. Bom in a Parsi household in Mumbai, Cooper edited ‘India’s Stamp Journal’. He was the founder of the first Philatelic Bureau in India, an , office that collected stamps. He founded the ‘Empire of India Philatelic Society’. He went on to write many , books on this subject. He gave a scientific bend to his , hobby. He played a pivotal role in taking the study of Indian postage stamps to the international level, , Having started his career as a postage stamp collector, Cooper achieved the expertise of a philatelist at the international level. The postage stamp on Jal Cooper , is an important source to understand his significant ,contribution to this field.

Question 1.
Other than Philatelies which other streams of vocation deal with sources of history?
Answer:
Other than Philatelies, other streams of vocation which deal with sources of history are: Numismatics, Museology and Archaeology.

Question 2.
Name the two institution founded by Jal Cooper.
Answer:
Two institutions founded by Jal Cooper are:

(i) The First Philatelic Bureau in India.
(ii) Empire of India Philatelic Society.

Question 3.
Why do you think the government of India issued a postage stamp in the name of Jal Cooper?
Answer:
Jal Cooper is accredited to raise Indian Philatelies to an international level. He nurtured his hobby with great expertise and became a renowned Postage Stamp Collector. To honour his contribution, the government of India issued a postage stamp in his name in 1977.

Answer the following questions in detail.

Question 1.
Which information among print media is considered authentic and trustworthy?
Answer:
Among the print media, the information contained in the annual issues of the Publications Division of the Government of India is authentic and trustworthy.
(ii) For example, the Information and Broadcasting Department published ‘INDIA 2000’, an annual reference book.
(iii) ‘ This reference book is created under ‘Research, Reference and Training Department’.

Question 2.
Which sources are included in material sources?
Answer:
The following sources are included in material sources:

Coins
Places of worship
Things in daily use
Royal seals
Ornaments
Museums
Clothing
Modern architecture.

Question 3.
Write in brief about museums in India.
Answer:
(i) All states of India have museums that depict the characteristics and display the cultural and social heritage of the state.
(ii) They enable us to understand history (e.g., the Chhatrapati Shivaji Maharaj Museum at Mumbai, Reserve Bank Museum in Pune city).
(iii) Apart from the Government Museums, some private collectors also set up their own museums.
(iv) They are based on distinctive subjects; For example, coins, notes, lamps and nutcrackers in different shapes, cricket equipment, etc.

Question 4.
Write briefly about ‘Indian News Review’.
Answer:
(i) An institute called Indian News Review has produced various newsreels on important events in politics, social issues, art, sports and culture.
(ii) This department has also produced various documentaries on prominent social leaders, on people who have made major contributions for the country and about important locations in India.
(iii) These news releases and documentaries are useful for studying the history of modern India.

Question 5.
Oral Sources
Answer:
(i) These sources include folktales, folksongs, proverbs, ballads and owis (Marathi verses in the oral tradition).
(ii) Activists were inspired by the powadas of Lok shahir, Anna Bhau Sathe and Shahir Amar Sheikh during the Sanyukta Maharashtra Movement.

Question 6.
Identify the picture and give relevant information.
Maharashtra Board Class 9 History Solutions Chapter 1 Sources of History 5
Answer:

The person depicted in the picture is Jal Cooper, an internationally acclaimed philatelist from India.
Cooper edited ‘India’s stamp Journal’. He was the founder of the First Philatelic Bureau in India, an office that collected stamps. He founded the ‘Empire of India Philatelic Society’.
The Government of India issued the Jal Cooper Stamp in 1977.

9th Std History Questions And Answers:

Std 9 Political Science Chapter 6 Question Answer Maharashtra Board

February 6, 2025January 4, 2025 by Bhagya

Balbharti Maharashtra State Board Class 9 Political Science Solutions Chapter 6 International Problems Notes, Textbook Exercise Important Questions and Answers.

International Problems Class 9 Questions And Answers Maharashtra Board

Class 9 Political Science Chapter 6 International Problems Questions And Answers Maharashtra Board

Political Science Class 9 Chapter 6 Question Answer Maharashtra Board

1. Choose the right option and rewrite the sentence:

Question 1.
Which among the following is an International problem?
(a) Border dispute between Maharashtra and Karnataka
(b) Kaveri water sharing question
(c) Problems of refugees
(d) Naxalism in Andhra Pradesh
Answer:
(c) Problems of refugees

Question 2.
Which among the following rights are not included in human rights?
(a) Right to work
(b) Right to information
(c) Children’s rights
(d) Equal pay for equal work
Answer:
(b) Right to information

Question 3.
Which among the following days is observed at an international level?
(a) Teachers’ Day
(b) Children’s Day
(c) Earth Day
(d) Flag Day
Answer:
(c) Earth Day

2. Explain with reasons whether the following statements are true or false:

Question 1.
It is necessary that all the nations should cooperate in order to find remedies of environmental degradation.
Answer:
True.

The threat to the environment caused by pollution or by leakage of oil or gas does not remain restricted to one nation.
Its effects are long term so it becomes necessary for nations to act with each other’s consent and cooperation in order to deal with these effects.

Question 2.
Sino-Indian relations are friendly.
Answer:
False.
The conflict between India and China is connected to two issues

Border issue and
Status of Tibet. India made several efforts to sort this border dispute by means of dialogue. But it has not met with much success.

3. Complete the following chart:

Question 1.
Human Rights
Maharashtra Board Class 9 Political Science Solutions Chapter 6 International Problems 6
Answer:

Question 2.
Degradation of the Environment
Maharashtra Board Class 9 Political Science Solutions Chapter 6 International Problems 8
Answer:

Question 3.
Terrorism
Maharashtra Board Class 9 Political Science Solutions Chapter 6 International Problems 10
Answer:

4. Prepare the following concept map:

Question 1.
Maharashtra Board Class 9 Political Science Solutions Chapter 6 International Problems 13
Answer:

5. Write your own opinion about :

Question 1.
Explain India’s position in establishing human rights.
Answer:
(i) The Preamble of the Indian Constitution contains the objectives of the Constitution.

(ii) It secures to its citizens: justice, social, economic and political; Liberty of thought, expression, belief, faith and worship; Equality of status and opportunity; and Fraternity assuring the dignity of the individual and unity and integrity of the Nation.

(iii) Fundamental Rights are assured to all the citizens of India.

(iv) In order to make these objectives effective, Fundamental Rights and Directive Principles of State Policy were incorporated in Part III and Part IV of our Constitution.

(v) The Supreme Court of India and the High Courts of all states issue Writs, such as:

Habeas Corpus
Mandamus
Prohibition
Certiorari
Quo Warranto to protect human rights.

Question 2.
Narrate the effects of terrorism and suggest remedies to control it.
Answer:
(i) The 21st century terrorism is an organised system of violence and intimidation. There is a need to empathise, understand, cooperate and coordinate our efforts in dealing with terrorism at the national and international level.

(ii) Terrorism includes taking hostages; firing or bombing civilian localities that are undefended such as hospitals or schools, inhuman treatment to prisoners and destruction of property.

(iii) This leads to feeling of insecurity and helplessness among the people who are prone to terrorism. Their faith in social security and police protection is lowered and they may be psychologically affected.

(iv) Terrorism affects economic growth, political stability and social welfare of the people. It burdens our defence and police system as well. Hence the government cannot focus on its constructive programmes.

(v) Citizens should be alert about unattended luggage or bags at public places and be vigilant about suspicious men around them. They must immediately report to the authorities about the same.

(vi) The youth of the nation should volunteer in police and armed forces. The civilians must always cooperate with the police and government authorities to nab the terrorists.

Class 9 Political Science Chapter 6 International Problems Additional Important Questions and Answers

Choose the correct option from the given options and rewrite the statements:

Question 1.
United Nations Conference on human environment was called at Stockholm from ________.
(a) 5th to 16th June, 1972
(b) 5th to 16th July, 1972
(c) 5th to 16th June, 1971
(d) 5th to 16th July 1971
Answer:
5th to 16th June, 1972

Question 2.
The United Nations General Assembly adopted the International Covenant on Civil and Political Rights (ICCPR) in ______.
(a) 1948
(b) 1966
(c) 1964
(d) 1962
Answer:
1966

Question 3.
In 1997, the conference at Kyoto laid down the protocols for the developed countries for preventing climate change. For how many years did it come to be applied?
(a) 10 years
(b) 12 years
(c) 15 years
(d) 16 years
Answer:
15 years

Question 4.
How many Articles are there in the United Nations Declaration of Human Rights?
(a) 30
(b) 20
(c) 40
(d) 50
Answer:
30

Question 5.
When was the Declaration of the Rights of Child proclaimed?
(a) 30th November 1959
(b) 20th November 1959
(c) 20th December 1959
(d) 30th December 1959
Answer:
20th November 1959

Question 6.
When was the first Earth Day celebrated?
(a) 21st April, 1970
(b) 22nd April, 1970
(c) 23rd April, 1970
(d) 20th April, 1970
Answer:
22nd April, 1970

Question 7.
What led to the boycott of the regime in South Africa?
(a) Expatriation of Prisoners of War
(b) Racial Segregation
(c) Disobedience of the UN
(d) Asylum to international terrorists
Answer:
Racial Segregation

Question 8.
Which conference in 1997 laid down the protocols for developed countries for prevention of climatic changes?
(a) Conference at Copenhagen
(b) Conference at Amsterdam
(c) Conference at Kyoto
(d) Conference at Shimla
Answer:
Conference at Kyoto

Question 9.
Which institute/organisation is responsible for taking action against violation of human rights?
(a) Self Help Groups and NGOs
(b) Human Rights Commission
(c) Corporate bodies
(d) National Investigation Agency
Answer:
Human Rights Commission

State whether the following statements are true or false with reasons:

Question 1.
Human rights are necessary for living as a human being.
Answer:
True.
The concept of human rights has emerged from the concept of natural rights. Natural rights are those rights that we are endowed with because we are bom as human beings. In the same vein, human rights are those rights that are necessary for living as a human being.

Question 2.
The scope of human rights is limited.
Answer:
False.
The scope of human rights has in fact, broadened due to several issues of global nature like contagious diseases, the threat to environment, natural disasters, etc. Human rights today also include goals like protection of the environment and sustainable development.

Question 3.
Only internal security is threatened due to terrorist attacks.
Answer:
False.
The aim of a terrorist attack is not to endanger the geographical boundaries, but to challenge a regime in a country or refuse to acknowledge the existence of the State. This means that due to increasing terrorism, the internal security of a country is threatened in addition to its external security.

Question 4.
Once the refugees reach a safe place, they have new challenges.
Answer:
True.
Once the refugees reach a safe place, they need to find work, a place to live and other problems of a day to day nature. If the language and culture in the other nation are different, then adjusting to that poses difficulties. There is also no assurance that the people of a nation which gives shelter to the refugees will accept them.

Explain the concept:

Question 1.
Human Rights
Answer:
The concept of human rights has emerged from the concept of natural rights. Natural rights are those rights that we are endowed with because we are born as human beings. Human rights are those rights that are necessary for living as a human being and as a constituent of society.

Question 2.
Refugees
Answer:
People who have to leave their motherland against their wishes or are forced to go to other nations, seeking refuge or for security are called as refugees. People become refugees due to torture or persecution for belonging to a particular race or religion, due to war or a disaster, etc. In such situations people are forced to leave their own country and seek shelter in another country.

Question 3.
Terrorism
Answer:
Terrorism is spreading fear and terror in a society by using or threatening to use violence against common and innocent people for achieving political goals. Terrorism can be described as organised and planned violence.

Question 4.
Traditional War
Answer:
Traditional war is a conflict between two or more sovereign states. In such wars, the geographical boundaries between nations acquire importance, i.e. national security is connected with geographical boundaries.

Question 5.
Stockholm Conference 1972.
Answer:
(i) In order to discuss the immediate and long term problems related to the environment and to find solutions on them, a United Nations Conference on human environment was called at Stockholm from 5th to 16th June, 1972.

(ii) It was stressed that it is the responsibility of all nations to cooperate to overcome pollution.

(iii) The developing nations feel that the developed nations are more responsible for the decline of the environment and they should take the responsibility for stopping the decline.

(iv) Non-governmental organisations working in the field of environmental protection were also present and assumed a bigger role in the decision making process at international conferences regarding the environment.

(v) The issue of the protection of the common global wealth was raised.

(vi) A consensus emerged that it was the responsibility of all the nations to protect these resources.

(vii) It was after this conference that the United Nations created the United Nations Environment Programme (UNEP).

(viii) Many international treaties about environment were signed after this conference.

(ix) Several rules were made about the protection of environment. Environmental movements started on a large scale at national as well as at the international level.

Complete the following Chart/Concept Maps:

Question 1.
Maharashtra Board Class 9 Political Science Solutions Chapter 6 International Problems 2
Answer:

Question 2.
Maharashtra Board Class 9 Political Science Solutions Chapter 6 International Problems 4
Answer:

Answer the following questions in brief:

Question 1.
Which difficulties are faced by people who are forced to leave their own country?
Answer:
(i) When people of any country are forced to leave their own country as refugees, they have to face many problems.

(ii) The most important problem is to decide where to go. They have questions like will that nation give us shelter.

(iii) Secondly, they have to also take along with them other members of their family. It involves a lot of physical and emotional stress.

(iv) Apart from this, there are problems caused by natural elements like heat, rain, storms, as well as shortages of food, sickness, an enemy in pursuit, etc. In this process, many people lose their lives.

Question 2.
What was the Stockholm Conference of 1972 about?
Answer:
In order to discuss the immediate and long-term problems related to the environment and to find solutions to them, a United Nations Conference on human-environment was called at Stockholm from 5th to 16th June 1972.

Question 3.
What are the new challenges faced by refugees on reaching a safe place?
Answer:
(i) Once the refugees reach a safe place, they have new challenges. They need to find work, a place to live and other problems of a day to day nature.

(ii) If the language and culture in the other nation are different, then adjusting to that poses difficulties. There is no assurance that the people in the nation which gives shelter to the refugees will accept them.

Question 4.
What did the Environmental Conference of Rio (1992) emphasise on?
Answer:
(i) In this conference, the idea of sustainable development was stressed upon.

(ii) Different treaties regarding bio-diversity, climate change due to greenhouse gases, protection of forests, etc. were signed.

Question 5.
State the highlights of the conference on climatic change at Paris (2015).
Answer:
(i) A conference on climate change was held at Paris in November 2015.

(ii) An appeal was made in this conference that all nations should make concerted efforts to stop climate change and global warming and that the developed countries should help the developing countries to acquire the technology to achieve these goals.

Question 6.
What measures have been taken so far to save the refugees?
Answer:
(i) In 1951, some provisions were made regarding the question of refugees at the international level. One such provision was that the refugees will not be forcefully sent back to their country against their wishes.

(ii) Similarly an office of the High Commissioner of the United Nations has been established to solve their problems.

Question 7.
Give some examples of refugees.
Answer:
(i) Before the Second World War, the Jews were tortured in Germany.

(ii) Their citizenships and properties were confiscated. Due to this, the Jews became refugees.

(iii) In 1971, the people in East Pakistan turned refugees and came to India seeking refuge due to political and religious persecution.

(iv) In the last few years due to the war-like situation in Iraq and Syria, a lot of people are leaving Syria as refugees. We can cite many such example of refugees.

Question 8.
Which problems are faced by the host nation that agrees to provide shelter to the refugees?
Answer:
(i) As the number of refugees increases, the strain on the economy of the host nation increases. A shortage of essential goods is created; there may be an increase in crime or even inflation.

(ii) The locals may lose their jobs; a problem of law and order may crop up. Many such problems may emerge.

(iii) Due to these problems, many nations are not ready to give shelter to refugees and to resettle them.

Question 9.
Which steps can be taken for preservation of human rights?
Answer:
(i) If all nations safeguarded and fostered human rights, exploitation and violence would reduce. All people would be able to achieve their own development safely and securely.

(ii) Human rights could be more effectively implemented if the environment is safeguarded and if terrorism is completely wiped out.

(iii) No group of people will have to become refugees. For this, all nations have to come together, cooperate with each other, take concrete action and bring about actual change.

Question 10.
Many nations are not ready to give shelter to refugees. Why?
Answer:
Many nations are not prepared to give shelter to refugees because:

As the number of refugees increases, the strain on the economy of the host nation increases.
A shortage of essential goods is created; there may be an increase in crime or even inflation.
The locals may lose their jobs; a problem of law and order may crop up.
Many such problems may emerge.

Question 11.
The problems relating to the environment are inherently of a global nature. How?
Answer:
(i) The threat to the environment caused by pollution or by leakage of oil or gas does not remain restricted to one nation.

(ii) The visible effects of the decline of environment are extinction of species of plants and animals, decrease in the fertility of soil, water shortage, fluctuation in the proportion of rainfall, global warming, drying up of rivers and lakes, pollution of rivers and seas, incidence of newer diseases, acid rain, thinning of the ozone layer, etc.

(iii) Even if some of the effects are restricted to particular nations, these problems reach global proportions due to their long term effects, while some problems are inherently of a global nature.

Question 12.
How is terrorist war different from traditional war?
Answer:
(i) Terrorist conflict is different from traditional war.

(ii) Traditional war is a conflict between two or more sovereign states.

(iii) In such wars, the geographical boundaries between nations acquire importance, i.e. national security is connected with geographical boundaries.

(iv) On the other hand, in the case of terrorism, terrorist groups can cause violence in any part of the world from anywhere in the world.

(v) The aim of a terrorist attack is not to endanger the geographical boundaries, but to challenge a regime in a country or refuse to acknowledge the existence of the state.

9th Std Political Science Questions And Answers:

Std 9 History Chapter 10 Question Answer Maharashtra Board

February 6, 2025January 4, 2025 by Bhagya

Balbharti Maharashtra State Board Class 9 History Solutions Chapter 10 Changing Life 2 Notes, Textbook Exercise Important Questions and Answers.

Changing Life 2 Class 9 Questions And Answers Maharashtra Board

Class 9 History Chapter 10 Changing Life 2 Questions And Answers Maharashtra Board

History Class 9 Chapter 10 Question Answer Maharashtra Board

1. Choose the proper option and rewrite the completed sentences:

Question 1.
India won the cricket world cup under the captainship of ______.
(a) Sunil Gavaskar
(b) Kapil Dev
(c) Sayyad Kirmani
(d) Sandip Patil
Answer:
(b) Kapil Dev

Question 2.
The _____ language is gaining importance in India due to the process of globalisation.
(a) Punjabi
(b) French
(c) English
(d) Hindi
Answer:
(c) English

2. Complete the information in the following table:

Question 1.

(1)	Important languages in India	…………
(2)	Players who have won medals at the Olympic games	……………
(3)	Childrens’ movies that you have seen	……………
(4)	Names of channels telecasting various news bulletins	……………..

Answer:

(1)	Important languages in India	Marathi, Hindi, Gujarati
(2)	Players who have won medals at the Olympic games	Karnam Malleswari, Abhinav Bindra, P.V. Sindhu
(3)	Childrens’ movies that you have seen	The Lion King, Minions, Finding Nemo etc.
(4)	Names of channels telecasting various news bulletins	DD News, CNN, ABP News

3. Give reasons for the following statements:

Question 1.
Cricket began to be played all over India, to a greater or smaller extent.
Answer:
Cricket began to be played all over India, to a greater or smaller extent because:-

In 1983, the Indian team won the World Cup for cricket, under the captainship of Kapil Dev. It was a historic victory.
Cricket instantly won great popularity across the country.
In the same year, Sunil Gavaskar broke the earlier record of maximum centuries in test cricket.
In 1985, India won the ‘Benson and Hedges’ World Championship of cricket. As a result, cricket came to be played in all States to a lesser or greater extent, but at the cost of indigenous Indian games.

Question 2.
The economy of movies is changing.
Answer:
(i) Movies in foreign languages are now translated. Even during the screening of English movies, a short Hindi translation now appears on the screen as sub-titles.

(ii) Hindi movies now compete with ‘global’ movies as they have reached every nook and comer of the world. We see a reflection of politics, social events, industry and technology in the movies.

(iii) Movies which were 3-4 hours long are now of only one or one and a half hours. Moreover, the concept of one screen and one cinema hall has given way to multiplexes.

(iv) The days of a movie running for 100 weeks in one cinema hall are over. Now one movie runs in thousands of cinema halls in India and abroad simultaneously.

(v) This development has changed the economy of movies. Production of movies has attained the status of industry.

(vi) The industry now employs crores of people. The movie industry in regional languages is also thriving.
Therefore the economy of movies is changing.

4. Answer the following questions in 25-30 words:

Question 1.
Why is it necessary to keep alive the dialects of Indian languages?
Answer:
(i) Hindi, Assamese, Bengali, Gujarati, Kannad, Kashmiri, Malayalam, Marathi, Odiya, Punjabi, Sanskrit, Tamil, Telugu, Urdu, Konkani,
Manipuri, Nepali and Sindhi are the official languages in India.
(ii) These Indian languages also have dialects, but their number is now on the decline.
(iii) Timely steps should be taken to nurture them, otherwise we will lose an important part of our heritage.
(iv) Nevertheless, Hindi, which has reached everywhere through the medium of Hindi movies, has served to unite the country by language.

Question 2.
Elaborate upon the changing scope of newspapers.
Answer:
(i) During early post-independence period, the newspapers were expected to not only give the news of daily events, but also give impetus to industry and commerce by printing advertisements.

(ii) Earlier, newspapers were black and white. With the changing times, colour printing became common.

(iii) Earlier, newspapers were thought to be the mouthpieces of the taluka or district. Now they have to face tough competition from the State level newspaper chains. But on the whole, newspapers are now becoming more active.

(iv) Their scope has enlarged to include raising funds for drought affected and flood affected people, helping meritorious students from lower income groups to go for higher education and organizing or sponsoring cultural programmes. This is how newspapers have now become an inseparable part of our lives.

Question 3.
What changes have taken place in the medium of television?
Answer:
(i) Television came to India during the post-independence period. Earlier it was black and white. Now it is coloured. Earlier it was limited to some selected programmes and fixed time-slots.

(ii) Gradually its scope was enlarged to include educational programmes, news bulletins, detailed reporting of the tours of the President and the Prime Minister.

(iii) During the telelcast of Ramayana and Mahabharat, a majority of the people used to sit glued to the television set. These serials proved the popularity of this medium. Then in 1991, CNN channel showed to the entire world a live visual reporting of the Iraq war.

(iv) In 1998, STAR (Satellite Television Asia Region) a private media house entered India, and the uninteresting, monotonous and propagandist news telecasts of the early period underwent a sea change.

(v) The language, the technique of presentation, studios equipped with the latest technology and the use of OB (outdoor broadcasting) vans have expanded the scope of Indian T.V. channels still further, and brought in transparency and variety. Now, every nook and corner of the country is connected.

Class 9 History Chapter 10 Changing Life 2 Additional Important Questions and Answers

Choose the correct option from the given options and rewrite the statements:

Question 1.
_____ won the national championship of billiards for teenagers at the age of 15.
(a) Milkha Singh
(b) Rafael Nadal
(c) Geet Sethi
(d) Prakash Padukone
Answer:
(c) Geet Sethi

Question 2.
In________ STAR (Satellite Television Asia Region) a private media house entered India.
(a) 1995
(b) 1996
(c) 1997
(d) 1998
Answer:
(d) 1998

Question 3.
In 1991, _______ showed to the entire world a live visual reporting of the Iraq War.
(a) CNN
(b) CNBC
(c) HBO
(d) NDTV
Answer:
(a) CNN

Question 4.
The Kohima Radio station had to make its broadcast in __________ languages which included English, Hindi and Naga dialects.
(a) 28
(b) 26
(c) 24
(d) 25
Answer:
(d) 25

Identify and write the wrong pair in the following sets:

Question 1.
(1) Karnam Malleshwari – Weight lifting
(ii) Sunil Gavaskar – Ace Indian Cricketer
(iii) CNN – Iraq War
(iv) Star Television – Sponsoring cultural programmes
Answer:
Wrong Pair: Star Television – Sponsoring cultural programmes

Question 2.
(i) Kapil Dev -1983 World Cup
(ii) Geet Sethi – Benson and Hedges
(iii) Karnam Malleshwari – First woman to win a medal at Olympics
(iv) Sunil Gavaskar – Maximum centuries in test cricket
Answer:
Wrong Pair: Geet Sethi – Benson and Hedges

Question 3.
(i) India won Cricket World Cup – 1983
(ii) Karnam Malleshwari won a medal at Olympics – 2000 ’
(iii) Live telecast of Iraq War -1991
(iv) Star T.V. entered India -1992
Answer:
Wrong Pair: Star T.V. entered India -1992

Do as directed:

Question 1.
Complete the following concept:
Maharashtra Board Class 9 History Solutions Chapter 10 Changing Life 2 2
Answer:

Explain the statements with reason.

Question 1.
Hindi Movies have reached every nook and corner of the world.
Answer:
(i) In the field of entertainment, the place of Hindi movies is incomparable.
(ii) Now movies reflect contemporary themes. Film shooting locales have moved abroad.
(iii) So, viewers can now see many different places in foreign countries. Movies in foreign languages are now translated.
(iv) During the screening of English movies, a short Hindi translation now appears on the screen as sub-titles.
(v) Hindi movies now compete with ‘global’ movies as they have reached every nook and corner of the world.

Read the following passage and answer the questions:

Sports: During the pre-independence period, only a few selected games were known to people in general. Some sports persons changed this situation. This enhanced the status of both – the sports, and the sportspersons. For example, Geet Sethi achieved , global excellence in snooker, a variation of billiards. He won the national championship of billiards for teenagers at the age of 15. Later, he went on to win national and international championships. At the , global level, he won the amateur billiards competition thrice, and the professional one five times. His success made the game popular, and newspapers began to report news about billiards. Thus he made a new field available to rising sportspersons in India, It was in 1983, that the Indian team won the World , Cup for cricket, under the captainship of Kapil Dev. It was a historic victory. Cricket instantly won great , popularity across the country. In the same year, ‘Sunil Gavaskar broke the earlier record of maximum centuries in test cricket. In 1985, India won the ‘Benson and Hedges’ World Championship of cricket. As a , result, cricket came to be played in all States to a lesser or greater extent, but at the cost of indigenous Indian games. A few movies were also produced around the , theme of cricket. Live telecasts of the full five days or , one day of the matches also became available.
India had been participating in Asiad and Olympic of year 2000, Karnam Malleshwari won a medal for, weight-lifting. She was the first Indian woman to win , a medal at the Olympics. India’s representation began to rise in various Olympic games such as hockey, badminton, tennis, swimming, weightlifting and archery.

Question 1.
Which two cricket tournaments mentioned in the passage records a victory for India?
Answer:
World Cup 1983 and Benson and Hedges -1985 are the two tournaments mentioned in the passage that recorded victory for India.

Question 2.
Who was the first Indian woman to win a medal at the Olympics? Which sport did she represent?
Answer:
Karnam Malleshwari was the first Indian Women to win a medal for India at Olympic. She represented India in Women’s Weight Lifting.

Question 3.
Why do you think cricket has overshadowed other indigenous Indian Games?
Answer:
Cricket was introduced in India by the British. In the post independence period this game was mostly played by the elite. In times to come, cricket gained glamour and popularity across the nation gradually giving a setback to other indigenous games in India. Since cricketers received more professional coaching, funding and infrastructural facilities as compared to players of other games, it became inevitable that other games in India were overshadowed.

Answer the following questions in detail:

Question 1.
Do you think English has threatened our indigenous languages? How?
Answer:
(i) Hindi, which has reached everywhere through the medium of Hindi movies, has served to unite the country by language.
(ii) However, English language has been gaining ground in India due to the process of globalisation which began after 1990.
(iii) English opens the doors to multiple job opportunities. Moreover, Indians are at the forefront in learning English.
(iv) However, it is necessary to ensure that this process does not endanger the very existence of regional languages.

Question 2.
Explain the contribution of Geet Sethi and Kamam Malleswari to the field of sports.
Answer:
(i) Geet Sethi:

Geet Sethi achieved global excellence in snooker, a variation of billiards.
He won the national championship of billiards for teenagers at the age of 15.
Later, he went on to win national and international championships.
At the global level, he won the amateur billiards competition thrice, and the professional one five times.
His success made the game popular, and newspapers began to report news about billiards.

(ii) Karnam Malleswari: At the Olympics of the year 2000, Karnam Malleswari won a medal for weightlifting. She was the first Indian woman to win a medal at the Olympics.

9th Std History Questions And Answers:

Std 9 Political Science Chapter 3 Question Answer Maharashtra Board

February 6, 2025January 4, 2025 by Bhagya

Balbharti Maharashtra State Board Class 9 Political Science Solutions Chapter 3 India’s Defence System Notes, Textbook Exercise Important Questions and Answers.

India’s Defence System Class 9 Questions And Answers Maharashtra Board

Class 9 Political Science Chapter 3 India’s Defence System Questions And Answers Maharashtra Board

Political Science Class 9 Chapter 3 Question Answer Maharashtra Board

1. Choose the right option and rewrite the sentence:

Question 1.
The ______ of India is the Commander-in-Chief of all the Defence forces.
(a) President
(b) Prime Minister
(c) Defence Minister
(d) Governor
Answer:
(a) President

Question 2.
The ______ has the responsibility of protecting the coastline.
(a) Army
(b) Coast guard
(c) Border Security Force
(d) Rapid Action Force
Answer:
(b) Coast guard

Question 3.
The _______ has been established with the purpose of instilling among students the love of discipline and military training.
(a) Border Security Forces (BSF)
(b) Central Reserve Police Force (CRPF)
(c) National Cadet Corps (NCC)
(d) Rapid Action Force (RAF)
Answer:
(c) National Cadet Corps (NCC)

2. Explain with reasons whether the following statements are true or false:

Question 1.
It is necessary to end terrorism to ensure human security.
Answer:
True.

The biggest challenge to human security is that of terrorism.
Terrorism targets common, innocent people.
It aims at creating terror or fear in their minds, so that they begin to feel insecure.
Thus, in order to protect human security, it is necessary to put an end to terrorism.

Question 2.
Every nation creates a strong security system for itself.
Answer:
True.

National Security is closely connected with geography because national security is more likely to be endangered by nations who are geographically closer.
A nation must assess the threat to its geographical boundaries and the source of that threat.
In order to keep this threat at bay, the nation has to increase its military might.
The nation has to use modem technology to predict the threat, to build weapon systems and modernize and update the defence forces.

Question 3.
There are no issues of dispute between India and Pakistan.
Answer:
False.

There are several disputes between India and Pakistan. For example, the Kashmir issue, disputes over river water sharing, the problem of infiltrations, dispute over the border, etc.
India has continually tried to solve these issues through discussion and negotiations

3. Write short notes:

Question 1.
The functions of the Rapid Action Force
Answer:
The Rapid Action Force performs the task of bringing people’s lives to normalcy by moving in quickly in incidents of the threat to National Security such as bomb blasts or riots.

Question 2.
Human Security
Answer:
(i) In the Post – Cold War period, the concept of National Security changed and became broader. National Security is not just the security of the country but also of the people living in it, because security is ultimately for the people.

(ii) Hence; human security refers to human-centric thinking. In human security, it is expected that human beings should be protected from all sorts of dangers and they should be given the opportunities of education, health and development.

(iii) The concept of human security also includes the idea that a conducive environment should be created for everybody to live a respectable life by overcoming illiteracy, poverty, superstition, backwardness, etc. Human security necessitates the protection of the rights of minorities and weaker sections

Question 3.
Home Guards
Answer:
(i) This organisation was established in the pre-independence period. Citizens can join the Home Guards and assist in the defence of the country.

(ii) Any citizen, man or woman, between the age of 20 and 35 years can join the Home Guards.

(iii) This force has the following tasks: Maintain public security, supply of milk, water and other essential services during riots or strikes, to regulate traffic, to help people at the time of natural disasters like floods, earthquakes, etc.

4. Give your own opinion about:

Question 1.
Which of the forces related to India’s security would you like to join? Why?
Answer:
(i) If given a chance I would like to join the Indian Army.

(ii) India is surrounded by neighbours like Pakistan and China which have posed many threats to India’s territorial security through infiltration and cross-border terrorism.

(iii) The Arfny is thus the most challenging place to be, where service to protect the motherland would be valued the most.

(iv) The determination, discipline and patriotism which are intrinsic virtues of the Indian Army have always inspired me to do my bit for the nation.

(v) The training for physical fitness and the skills of various war operations can be best received through the Indian Army.

(vi) For these reasons I hold the Indian Army as the most sought after career and the ultimate destination of my life.

Question 2.
Give your views on the policy ‘Atoms for Peace’.
Answer:
(i) US nuclear policies had failed to prevent further nuclear proliferation, fuelled the arms race, suppressed the humanitarian benefits of civil nuclear technology and badly affected the development of the US nuclear industry.

(ii) In his “Atoms for Peace” speech of 1953, President Dwight D. Eisenhower captured the tensions and the ironies of the atomic age.

(iii) Eisenhower believed only nuclear preparedness offered protection; while nuclear weapons lead to war. Nuclear power offered progress and hope.

(iv) However, the motives behind Atoms for Peace extended beyond non-proliferation, arms control, and economic interests.

(v) Objective of the Eisenhower Administration was to set USA advantageously against USSR.

(vi) He envisaged to permit privatization and commercialization of fuel technologies, cooperation with foreign partners, and international nuclear commerce.

(vii) Ultimately, Atoms for Peace yielded billions of dollars in civil nuclear commerce for the US economy.

(viii) Atoms for Peace provided political cover for the biggest nuclear arms build-up in US history, and helped fuel the Cold War arms race.

5. Answer the following questions in brief:

Question 1.
What are the threats to National Security?
Answer:
(i) India’s security is not only threatened by outside powers, but also from within. It is not just the difference between external security and internal security that is important anymore.

(ii) Religion, regionalism, several rebellious movements based on ideology, race-ethnicity and economic inequality are creating instability. For example, the Naxalite movement is a threat to India’s internal security.

Question 2.
Write the functions of the Border Security Force.
Answer:
The Border Security Force performs tasks like:

creating a sense of security in the minds of people living in areas near the border,
preventing smuggling,
patrolling the border, etc.

6. Do as directed:

Question 1.
Complete the table about security forces:

Name of the Security Forces	Functions	Chief	Name of the Present Chief
Army	………….	……….	………..
……….	………….	Admiral	………….
………….	Protection of India’s air space	…………….	…………..

Answer:

Name of the Security Forces	Functions	Chief	Name of the Present Chief
Army	Protection of geographical boundaries	General	Manoj Mukund Naravane
Navy	Protection of the coast line	Admiral	Karambir Singh
Air Force	Protection of India’s air space	Air Chief Marshall	Rakesh Kumar Sing Bhadavria

Question 2.
Maharashtra Board Class 9 Political Science Solutions Chapter 2 India’s Foreign Policy 2
Answer:

Class 9 Political Science Chapter 3 India’s Defence System Additional Important Questions and Answers

Choose the correct option from the given options and rewrite the statements:

Question 1.
The ______ forces are responsible for protection and security of important locations.
(a) Paramilitary Forces
(b) Research and Analysis Wing
(c) Central Bureau of Investigation
(d) Interpol
Answer:
(a) Paramilitary Forces

Question 2.
The Air Force is in charge of protecting India’s ______.
(a) Borders
(b) Coastline
(c) Airspace
(d) Mineral Resources
Answer:
(c) Airspace

Question 3.
The Indian Army is the world’s ____ largest army.
(a) Second
(b) Fifth
(c) Seventh
(d) Third
Answer:
(c) Seventh

Question 4.
The Chief of Navy is known as ________.
(a) Admiral
(b) General
(c) Marshall
(d) Brigadier
Answer:
(a) Admiral

Question 5.
The National Defence Academy is at ______.
(a) Pune
(b) Dehradun
(c) Mumbai
(d) Delhi
Answer:
(a) Pune

Question 6.
_______ are neither completely military forces nor completely civil forces.
(a) Border Security Forces
(b) Paramilitary Forces
(c) Coast Guards
(d) Home Guards
Answer:
(b) Paramilitary Forces

Question 7.
The biggest challenge to human security is that of ______.
(а) Pollution
(b) Terrorism
(c) Natural calamities
(d) Corruption
Answer:
(b) Terrorism

State whether the following statements are true or false with reasons:

Question 1.
Naxalite Movement is a threat to India’s internal security.
Answer:
True.

India’s security is not only threatened by outside powers but also from within.
It is not just the difference between external security and internal security that is important anymore.
Example naxalite movement is a threat to internal security.

Question 2.
There are no training institutes in our country for military personnel.
Answer:
False.

Many training institutes have been set up in our country.
To train military personnel, so that they can perform their task.
Example – National Defence Academy – Pune

Do as directed:

Question 1.
Complete the table about paramilitary forces.

Paramilitary Forces	Prime Functions
Rapid Action Force	……………
Border Security Force	……………
Coast Guards	……………..
Central Reserve Police Force	……………..
Home Guards	……………
National Cadet Corps	………….

Answer:

Paramilitary Forces	Prime Functions
Rapid Action Force	Bringing life to normalcy after contingencies like blasts and riots.
Border Security Force	Patrolling and securing borders.
Coast Guards	Protecting the Indian maritime borders and preventing smuggling along sea routes.
Central Reserve Police Force	Helps the administration in the states to maintain law and order.
Home Guards	Maintaining public security, essential supplies and services during natural disasters and regulating traffic.
National Cadet Corps	Instilling love of discipline and military training.

Answer in brief:

Question 1.
What kind of conflicts may arise among sovereign nations?
Answer:
(i) There are disputes among nations over boundaries or sometimes conflicts emerge among them over water sharing.

(ii) Some other reasons for conflict could be: not following the terms of international treaties, constantly competing against each other and the influx of refugees from neighbouring countries.

Question 2.
What does the Central Reserve Policy Force do?
Answer:
The Central Reserve Police Force helps the administration in various states to maintain law and order.

Question 3.
Describe the three major armed forces in India.
Answer:
(i) India’s security system includes the Army, the Navy and the Air Force, the three forces that defend the country.

(ii) The responsibility of protecting the geographical boundaries is on the Army, whereas the Navy protects the coastline.

(iii) The Air Force is in charge of protecting India’s air space.

(iv) The Ministry of Defence controls all the three forces.

(v) The Indian Army is very big. It is the world’s seventh-largest. Its Chief is known as the General.

(vi) The Chief of Navy is known as the Admiral, while the Chief of the Air Force is known as Air Chief Marshall. These three chiefs are appointed by the President.

Question 4.
Which measures have been taken to modernize India’s security system?
Answer:
(i) Many measures are taken so that all three defence forces in India’s security system are adequately modernized. For this, some research institutions have been set up.

(ii) Many training institutes have also been set up in our country to train the personnel of all ranks of our defence forces so that they can perform their task competently.

(iii) For example, the National Defence Academy (NDA) at Pune and the National Defence College (NDC) at Delhi, etc.

Question 5.
How do environmental issues threaten human security?
Answer:
(i) Pollution and other changes in the environment have threatened human life. Diseases like AIDS, Chikungunia, Swine flu and Ebola have presented a big challenge.

(ii) Protecting human beings from such diseases is also considered as a factor of human security.

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9th Std Political Science Questions And Answers:

The Muscular System and Digestive System in Human Beings Class 7 Science Chapter 12 Questions And Answers Maharashtra Board

January 4, 2025January 3, 2025 by Bhagya

Balbharti Maharashtra State Board Class 7 Science Solutions Chapter 12 The Muscular System and Digestive System in Human Beings Notes, Textbook Exercise Important Questions and Answers.

Std 7 Science Chapter 12 The Muscular System and Digestive System in Human Beings Question Answer Maharashtra Board

Class 7 Science Chapter 12 The Muscular System and Digestive System in Human Beings Question Answer Maharashtra Board

1. Fill in the blanks with the right word from the brackets:

Question a.
The process of digestion starts from the ………….. (stomach, mouth).
Answer:
mouth

Question b.
Eyelids have …………… muscles. (voluntary, involuntary)
Answer:
involuntary

Question c.
……………. is not a function of muscular system. (production of blood cell, performing movement)
Answer:
Production of blood cells

Question d.
Muscles of the heart are …………….. . (ordinary muscles, cardiac muscles)
Answer:
cardiac muscles

Question e.
Pushing forward the food that has been chewed is the function of the …………… . (stomach, oesophagus)
Answer:
Oesophagus.

2. Find a match for me.

Question a.

Column ‘A’	Column B’
1. Cardiac muscle	a. Always functions in pairs
2. Are brought about by muscle	b. We never feel tired
3. Pepsin	c. Uncontrolled and painful contraction of muscles
4. Cramps	d. Chewing movement of the jaw
5. Skeletal muscles	e. Enzymes of the gastric juice

3. Who is telling a lie?

Question a.

Organ	Statement
1. Tongue	a. My taste buds can tell only a sweet taste.
2. Liver	b. I am the largest gland in the body.
3. Large intestine	c. I am 7.5 metre long.
4. Appendix	d. Digestion is impossible without me
5. Lung	e. I play an important role in excretion.

Answer:

Lie. My taste buds can tell all tastes – sweet sour, bitter.
Truth.
Lie. It is 1.5 metre long.
Truth.
Lung → Lie. It plays important role in breathing.

4. Give reasons.

Question 1.
Food becomes acidic in the stomach.
Answer:

The gastric glands of stomach secrete gastric juice.
Food that has entered stomach is churned.
Three components of gastric juice namely hydrochloric acid, pepsin and mucus are mixed with food here and the food becomes acidic.

Question 2.
Cardiac muscles are said to be involuntary muscles.
Answer:

Cardiac muscles are found in the heart.
These muscles bring about the contraction and relaxation (beating) of the heart.
Their movement is involuntary.
Cardiac muscles cause our heart to relax and contract continuously at a rate of about 70 times per minute. They do not depend upon our will.
Beating is carried out in their own fixed manner.

So cardiac muscles are said to be involuntary muscles.

Question 3.
Intoxicating substances should not be consumed.
Answer:

Physical health is important for our organ system to function properly.
But harmful habits like smoking, chewing of tobacco, drinking alcohol affect our health adversely.
If we consume any tobacco products, the mouth, pharynx, alimentary canal, and other organs of the digestive system cannot function properly.
It causes problems like vomiting, nausea, and headache.
Tobacco particles stick to teeth, gums, and skin of the mouth cavity and slowly cause injury to those parts resulting in their dysfunction.
This causes swelling of the gums and pain when moving the jaws.
The pharynx and intestine become inflamed it progress into cancer leading to death.

Question 4.
Your muscles should be strong and efficient.
Answer:
Muscles are bundles of fibres that can contract and relax as required.

The action of muscles is necessary for all kinds of movements from the small movements of eyelid to those that demand great strength when chopping wood with an axe.
We use muscles for various movements like talking laughing, walking, jumping, throwing etc.
Therefore our muscles should be strong and efficient to do our day today work well and smooth functioning of life processes.

5. Answer the following.

Question a.
How many types of muscles are there? Which are those types?
Answer:
Muscles are bundles of fibres that can contract and relax as required. There are three types of muscles.

Skeletal muscles.
Heart or cardiac muscles.
Smooth muscles.

1. Skeletal muscles: (a) Skeletal muscles work with bones, the two ends of each of these muscles are attached to two different bones. (b) They are responsible for holding the bones of the skeleton together and giving shape to our body, (c) Skeletal muscles permits movement of t the body and maintain the posture of the body. (d) Skeletal muscle is voluntary e.g. muscles in our arms and legs are voluntary muscles, their action depends upon our will. That’s why they are called voluntary muscles.

2. Heart or cardiac muscles: (a) Heart or cardiac muscles bring about the contraction and relaxation (beating) of the heart. (b) Their movement is involuntary, (c) Cardiac muscles cause our heart to relax and contract continuously at a rate of about 70 times per minute, (d) Cardiac muscle is found in heart.

3. Smooth muscles: (a) These muscles are present in the internal organs other than the heart, e.g. muscles of the stomach, intestine, blood vessels, uterus etc. (b)Their movements are involuntary and slow, (c) They are not according to our will. (d) Various vital functions of our body such as digestion, respiration and movement of food material of which we remain quite unaware, are carried out by these special muscles.

Question b.
What causes the problem of acidity? What is its effect on the body?
Answer:

Stress is the main cause of acidity.
Hectic lifestyle and stress can lead to unhealthy or irregular meals, not good for digestion process, and this may cause acidity.
Other reasons are eating spicy food, drinking too much alcohol, missing meals, an empty stomach may lead to acidity.
Acidity leads to stomach upset, burning sensation in chest and stomach, constriction of blood vessels, weight gain, obesity, cardiovascular damage.

Question c.
Name the different types of teeth. What is the function of each type?
Answer:
There are four types of teeth, namely incisors, canines, pre-molars, and molars.
Each tooth is covered by a hard substance called enamel. Enamel is made up of calcium salt.
The process of digestion begins with the function of the teeth in the mouth.
1. Incisors: (a) These come in first 6-months of age. Incisors are the eight teeth in the front and centre four on top and four on bottom, (b) They are sharp and blade like for cutting food. e.g. for biting an apple, (c) We use them to take first bite of food.

2. Canines: (a) These are strong and pointed, sharpest of all for tearing food. e.g. to tear off a piece of tough meat, (b) They play important role in digestion of food, (c) They appear between 11 and 20 months of age.

3. Pre-molar: Pre molar share features of both canines and molars. (a) You can use them for grinding and chewing food. So that it becomes semi-liquid helping to gulp down the throat easily, (b) They are situated at each side of your mouth in deep settings, (c) They appear at the age of 10 years.

4. Molar: (a) These are broad and flat on top for crushing and grinding food. e.g. to grind up nutmeats. (b) Two teeth above and two teeth below, they appear at the age 11-13 years. (c) Molars are more prone to germ attack because of their remote location in our mouth.
So we should keep them clean.

6. Sketch and label a diagram of the digestive system and describe it in your own words.

Question a.
Sketch and label a diagram of the digestive system and describe it in your own words.
Answer:

Conversion of food into a soluble form and its absorption into the blood is called digestion.
The digestive system consists of the alimentary canal and digestive glands.
The total length of alimentary canal is about 9 metres.
Its main parts are the mouth, pharynx, oesophagus, stomach, small intestine, large intestine, rectum and anus.
The salivary glands, liver, pancreas are the digestive glands connected to the alimentary canal.
Different organs of the digestive system perform the function of digestion.
There are different stages in the process of digestion of food.
The process of digestion begins with the function of the teeth in the mouth, food is chewed into small pieces.
There are four types of teeth, incisors, canines, pre-molars and molars.
Saliva in the mouth contains enzymes, ptyalin, or amylase. It converts starch into maltose.

a. Oesophagus:

It is a tube leading from the pharynx to the stomach,
It pushes the food towards the stomach.

b. Stomach:

The large sac like part of the alimentary canal is called the stomach.
Food that has entered is churned.
The gastric glands of stomach secrete gastric juice which contain hydrochloric acid, pepsin and mucus.
They mix with food and food becomes acidic.
Mainly proteins are digested in stomach.
Due to the churning and actions of gastric juice, food become a semi-solid slurry which is pushed into the small intestine.

c. Small intestine: (6m long)

Bile secreted by liver mixes with food in small intestine,
Most of the digestion and absorption of food takes place here.

d. Large intestine: (1.5m long) only water is absorbed in the large intestine. Undigested remain is thrown out of the body through the anus.

Project:

Question 1.
Make charts about maintaining good health.

Question 2.
Design a power point presentation about the digestive system and present it in the class.

Class 7 Science Chapter 12 The Muscular System and Digestive System in Human Beings Important Questions and Answers

Choose and write the correct word.

Question 1.
The structure that connects bones to the muscles is the ………………….. .
(a) ligament
(b) tendon
(c) fascicle
(d) skin
Answer:
(b) tendon

Question 2.
………………….. is not performed by muscles.
(a) Motion
(b) Excretion
(c) Maintenance of posture
(d) Heat production
Answer:
(d) Heat production

Question 3.
Approximately ………………….. skeletal muscles are there in the human body.
(a) 1000
(b) 600
(c) 100
(d) 60
Answer:
(b) 600

Question 4.
Most of the fat digestion occurs in ………………….. .
(a) rectum
(b) stomach
(c) small intestine
(d) large intestine
Answer:
(c) small intestine

Question 5.
Protein digestion is accomplished in ………………….. .
(a) stomach
(b) ileum
(c) rectum
(d) duodenum
Answer:
(b) ileum

Question 6.
The main function of the muscular system is ………………….. .
(a) excretion
(b) digestion
(c)movement
(d) contraction
Answer:
(c)movement

Question 7.
The largest muscle of our body is in the ………………….. .
(a) arm
(b) face
(c) thigh
(d) None
Answer:
(c) thigh

State whether True or False. Correct the false statement and rewrite:

Question 1.
Saliva is mixed with food in the mouth.
Answer:
True.

Question 2.
Gastric juice makes food alkaline.
Answer:
False. Gastric juice makes food acidic.

Question 3.
Pancreas is the largest gland in the body.
Answer:
False. Liver is the largest gland in the body.

Question 4.
Food becomes acidic in stomach.
Answer:
True

Question 5.
Cardiac muscles are said to be voluntary muscles.
Answer:
False. Cardiac muscles are involuntary.

Question 6.
Muscles contribute 60% of the weight of a healthy adult human body.
Answer:
False. Muscles contribute almost 40% of the weight of a healthy adult human body.

Question 7.
There are about 30 muscles in the human face.
Answer:
True

Question 8.
Muscles in our arms and legs have involuntary muscles.
Answer:
False. Muscles in our arm and legs are voluntary muscles.

Question 9.
Functions of organs like stomach, intestine, heart are carried out by voluntary muscles.
Answer:
False. Functions of these organs are carried out by involuntary muscles.

Question 10.
Smooth muscles are involuntary muscles.
Answer:
True.

Question 11.
The digestive function of the liver is to produce bile.
Answer:
True.

Question 12.
The muscular tissue has the ability to contract or shorten.
Answer:
True.

Find a match for me.

Question 1.

Column A’	Column B’
1. Salivary gland	a. Making food acidic
2. Liver	b. Regulation of sugar level
3. Pancreas	c. Digestion of carbohydrates
4. Stomach	d. Digestion of protein, fats, carbohydrate

Answer:

Column A’	Column B’
1. Salivary gland	c. Digestion of carbohydrates
2. Liver	d. Digestion of protein, fats, carbohydrate
3. Pancreas	b. Regulation of sugar level
4. Stomach	a. Making food acidic

Question 2.

Column ‘A’	Column B’
1. Saliva	a. Gastric juice
2. Juice in mouth	b. Bile
3. Juice produced by stomach	c. Ptyalin
4. Juice stored by gall bladder	d. Lubricates food

Answer:

Column ‘A’	Column B’
1. Saliva	d. Lubricates food
2. Juice in mouth	c. Ptyalin
3. Juice produced by stomach	a. Gastric juice
4. Juice stored by gall bladder	b. Bile

Question 4.

Column ‘A’	Column B’
1. Cardiac muscle	a. Inside of organs like stomach
2. Skeletal muscle	b. Found in heart
3. Smooth muscle	c. Attached to bones

Answer:

Column ‘A’	Column B’
1. Cardiac muscle	b. Found in heart
2. Skeletal muscle	c. Attached to bones
3. Smooth muscle	a. Inside of organs like stomach

Find the odd man out:

Question 1.
Stomach, esophagus, liver, small intestine, rectum
Answer:
Liver which is a gland and others are parts of digestive tract.

Question 2.
Saliva, bile, pancreatic juice, gastric juice chyme
Answer:
Chyme, it is a liquid food others are digestive juices.

Name the following:

Question 1.
Gastric juices in stomach
Answer:
Hydrochloric acid, Pepsin, Mucus.

Question 2.
Juices secreted by liver
Answer:
Bile.

Question 3.
Pancreatic juices.
Answer:
Trypsin, Lipase, Amylase.

Question 4.
Salivary gland secretion.
Answer:
Saliva

Question 5.
Enzyme present in saliva.
Answer:
Ptyalin or Amylase.

Question 6.
Types of muscles.
Answer:
Skeletal, Cardiac and Smooth muscles.

Question 7.
Study of muscles.
Answer:
Myology

Give scientific reason:

Question 1.
Skeletal muscles give shape to our body.
Answer:

Skeletal muscles are voluntary muscles. The two ends of each of these muscles are attached to two different bones.
Muscles of the arms and legs are skeletal muscles.
They are responsible for holding the bones of the skeleton together and giving shape to our body.

Question 2.
The process of digestion begins in the mouth.
Answer:

The process of digestion begins with the function of the teeth.
There are 4 types of teeth – incisors, canines, pre-molar, and molar.
They are responsible for grinding the food.
Saliva present in the mouth mixes with the food and makes it soft.
An enzyme present in saliva called ptyalin amylase converts starch into maltose. Thus, the process of digestion begins in the mouth.

Question 3.
Metabolic processes are impossible without enzymes.
Answer:

Enzymes are substances secreted’ in the body of an organism which bring about specific chemical reactions.
Enzymes are specific type of proteins. They are most active at normal body temperature.
Digestion enzymes of the digestive system bring about changes in the food material.
Food is digested with the help of enzymes and converted into more soluble and simple form.

Write short notes on:

Question 1.
Voluntary muscles
Answer:

Working with our hands, walking, eating are functions that depend upon our will.
Muscles used in these actions are called voluntary muscles, e.g. skeletal muscles are voluntary muscles.

Question 2.
Involuntary muscles
Answer:

Various processes like breathing, blood circulation, digestion are vital function, essential for life.
They do not depend upon our will.
The muscles of organs which carry out these involuntary functions are called involuntary muscles.
Functions of organs like the stomach, intestine, heart are carried out in their own fixed manner by involuntary muscles, e.g. cardiac muscle present in heart, smooth muscles in lining of stomach, small intestine, blood vessel, uterus.

Question 3.
Muscle and its types
Answer:
There are three types of muscles in body

Skeletal Muscles
Cardiac Muscles
Smooth Muscles

Question 4.
Digestive glands
Answer:
The salivary glands, liver and pancreas are the digestive glands connected to the alimentary canal.
1. Salivary glands: (a) Saliva is produced in the salivary glands in the mouth cavity, located in front of the ears, below the tongue, (b) It is carried to the mouth via ducts, (c) It is mixed with food during the process of chewing.

2. Saliva: contains an enzyme called Ptyalin or salivary amylase. Ptyalin convdrtfe starch into a sugar called maltose.

3. Liver: (a) The liver is the largest gland in the body, (b) Main function is storage of glucose, (c) The digestive juice secreted by the liver is bile, (d) Bile is carried into small intestine, it mixes with food and helps in digestion of fats.

4. Pancreas: The pancreas secretes the pancreatic juice that contains various enzymes

Trypsin → converts proteins into amino acids.
Lipase → converts fats into fatty acids, glycerol
Amylase → converts complex carbohydrate into simple sugar

Question 5.
Enzymes
Answer:
Enzymes are substances secreted in the body an organism which bring about specific chemical reactions.

Metabolic processes are impossible without enzymes.
Digestive exzymes of the digestive system bring about changes in the find material.
They break down the food into simple form.
They are a type of protein.
Saliva contain pytalin which converts starch into maltose.
- Trypsin: Convert proteins into amino acids.
- Lipase: Convert fats into fatty acid.
- Amylase: Converts complex carbohydrates into simple sugar.

Question 6.
Draw the structure of the different layers of the tooth.
Answer:

Differentiate between:

Question 1.
Voluntary and Involuntary muscles.
Answer:

Voluntary muscle	Involuntary muscle
1. Voluntary muscle means you can control it consciously.	1. Involuntary muscles are controlled by your subconscious. You have no control over them.
2. Skeletal muscles are voluntary muscles.	2. Cardiac muscles and smooth muscles are involuntary muscles.
3. Muscles in our arms and legs are voluntary muscles.	3. Muscles in heart, stomach, blood vessel, intestine are involuntary muscles.

Question 2.
Skeletal muscle and Cardiac muscle.
Answer:

Skeletal muscle	Cardiac muscle
1. Skeletal muscles are voluntary muscles.	1. Cardiac muscles are involuntary muscles.
2. Muscles in our arms and legs are voluntary muscles.	2. Muscles in heart, stomach, blood vessel, intestine are involuntary muscles.
3. They hold bones of the skeleton together and gives shapes to our body.	3. They bring about contraction and relaxation of heart.

Answer the following:

Question 1.
What is meant by organ system?
Answer:

There are different structural organizational levels in living organism.
Cells → tissues → organ → organ system → organism
Different organs together form one organ system.

Question 2.
How are the bones in our body joined to each other?
Answer:
Skeleted muscles join two bones with the help of tendons.

Can you tell?

Answer the following questions:

Question 1.
What is the mutual relationship between muscles and bones?
Answer:

Muscles are firmly attached to bones by means of tendons.
When muscles contract there is movement at the joint and there is pull on tendon which in turn pull on the bones to which they are attached.

Question 2.
Are the muscles of the different organs in our body identical?
Answer:
No, muscles of the different organs are not identical, some are voluntary, some are involuntary.

Question 3.
How do muscles perform their functions?
Answer:

Muscles in our body always work in groups.
When some muscles contract other muscles of the same group relax.
This is how muscles help in proper performance of the various functions of own body.

Answer the following questions:

Question 1.
Which parts of our body are made up only of muscles?
Answer:
Tongue, heart, stomach, liver, pancreas, intestines are made up of only muscles.

Question 2.
What would happen if the cardiac muscles do not move?
Answer:

Cardiac muscles cause our heart to relax and contract continuously at a rate of about 70 times per minute.
These muscles bring about the contraction and relaxation (beating) of the heart.
If the cardiac muscles do not move, heart will stop beating, and will not pump blood to other parts of the body and person will die.

Question 3.
Food enters the stomach and the stomach muscles do not move.
Answer:

Smooth muscles are present in the lining of stomach.
Their movement is responsible for churning of food.
If the muscles do not move, food will not be digested.

Question 4.
During digestion does all the food that we have eaten get converted into useful nutritive substances?
Answer:

During digestion not all the food is converted into useful nutritive substance, only whatever nutrients we obtain by digestion of food gets absorbed into the blood in small intestine.
Undigested remains of the food enters the large intestine and thrown out of the body through the anus.

7th Std Science Questions And Answers:

Substances in Daily Use Class 6 Science Chapter 6 Questions And Answers Maharashtra Board

January 4, 2025January 3, 2025 by Bhagya

Balbharti Maharashtra State Board Class 6 Science Solutions Chapter 6 Substances in Daily Use Notes, Textbook Exercise Important Questions and Answers.

Std 6 Science Chapter 6 Substances in Daily Use Question Answer Maharashtra Board

Class 6 Science Chapter 6 Substances in Daily Use Question Answer Maharashtra Board

1. Fill in the blanks using proper works:

Question a.
Rubber made by vulcanization is a …………… material.
Answer:
hard

Question b.
Man-made materials are made by …………… natural materials.
Answer:
processing

Question c.
…………… thread was developed simultaneously in New York and London.
Answer:
Nylon

Question d.
Rayon is also known as …………… .
Answer:
synthetic silk

2. Answer the following questions.

Question a.
Why did the need for man-made materials arise?
Answer:
The need for man-made materials arose due to the following reasons:

To meet the needs of an increasing population.
Human nature to try to make life more comfortable.
They can be made available in plenty at a low cost.
The reserve of natural substances is decreasing.

Question b.
Which are the natural materials obtained from plants and animals?
Answer:
Leather, jute, wool, cotton, silk are the natural substances obtained from plants and animals.

Question c.
What is vulcanization?
Answer:

Vulcanization is the process in which rubber is heated with sulphur for three to four hours.
Sulphur is mixed to give hardness to rubber.
The proportion of sulphur depends on the purpose for which the rubber is to be used.

Question d.
Which natural materials are used to obtain fibres?
Answer:
Cotton, wood pulp and various hydrocarbons obtained from mineral oils are used to obtain fibres.

3. What are we used for?

Question a.
What are we used for?
Answer:

Soil: It supports plant life and hence indirectly supports all living things. It is used for making clay pot, utensils, bricks etc.
Wood: It is used in paper industry. It is also used to make furniture.
Nylon: It is used to manufacture clothes, fishing nets, ropes, etc.
Paper. It is used in our textbooks, note books, currency notes, etc.
Rubber: It is used in the manufacture of erasers, tyres, rubber toys, rubber bands, etc.

4. How is paper manufactured? Write in your own words.

Question a.
How is paper manufactured? Write in your own words.
Answer:
Coniferous trees like pine trees are used to make paper.

The bark of the logs of these trees is first removed and the wood is broken into small pieces.
The mixture of these pieces with some chemicals is kept soaked for a long time to form pulp.
On completion of chemical process, fibrous substances from wood pulp are separated and some dyes are added.
The pulp is then passed through rollers, dried to form paper and finally wound on reels.

5. Give scientific reasons.

Question a.
We must use cotton clothes during summer.
Answer:

During summer we sweat more due to high temperature.
Cotton clothes absorb sweat.
Synthetic clothes are water repellent. They do not absorb sweat and we feel uncomfortable. Hence we must use cotton clothes in summer.

Question b.
We must observe economy in the use of materials.
Answer:

Due to excessive use of natural substances by human beings to fulfil their needs; they are getting depleted at a faster rate.
At the same time, it takes a very long time for these substances to get naturally formed again.
Hence, we must observe economy in the use of materials so that they are available for the future generation also.

Question c.
Saving paper is the need of the hour.
Answer:

Saving paper means saving trees as wood is used as the raw material to manufacture paper.
Trees are natural habitat for many Living things.
Trees help in increasing rainfall and water availability. Hence, saving paper helps in saving trees which in turn maintains balance in nature.

Question d.
Man-made materials have more demand.
Answer:

Man-made substances are waterproof, lightweight and easy for transportation.
Substances in Daily Use
They are easier to use and can be made available in plenty at a low cost.
Hence, there is more demand for man-made materials.

Question e.
Humus is a natural material.
Answer:

Humus is obtained from plant and animal wastes.
Micro-organisms act on these wastes and convert them into humus.
Hence, humus is a natural material.

6. Find out.

Question 1.
How is lac obtained from nature?
Answer:

Lac is a resinous substance secreted from the glands present in the skin of female lac insect.
Lac insects live on the Palash trees. In India lac is mainly produced in the states of Rajasthan and Bihar.

Question 2.
How are pearls obtained?
Answer:

Pearls are formed when a foreign particle such as a grain of sand or a small particle of rock accidentally enters the space between the mantle and shell of an oyster’s body.
Oysters cannot reject the particle, and as a defence mechanism its produces a shining coating called nacre on the particle layer by layer.
As the shiny layers get added, a pearl is formed.
Cultured pearls are artificially formed by inserting a bead in oyster shell and allowed to coat it with nacre over several years.

Activity:

Question 1.
Visit a rubber, paper or textile industry in your area and collect information about it.

Question 2.
Collect various samples of paper and note their uses.

Question 3.
Use blank pages from old note-books and make a new one.

Class 6 Science Chapter 6 Substances in Daily Use Important Questions and Answers

Fill in the blanks using proper works.

Question 1.
Natural rubber is obtained from …………… of trees.
Answer:
latex

Question 2.
Changes where the original constituent substances cannot be obtained again from the new substances are called …………… changes.
Answer:
irreversible

Question 3.
A paper factory in Maharashtra is situated at …………… .
Answer:
Ballarpur

Question 4.
Glass can be made from …………… and …………… .
Answer:
sand, calcium

Question 5.
Botanical name of rubber plant is …………… .
Answer:
Hevea brasiliensis

Question 6.
…………… obtained from mineral oils are used to make polymer chains.
Answer:
Hydrocarbons

Question 7.
The maximum production of rubber in India is in …………… .
Answer:
Kerala

Question 8.
…………… invented the process of vulcanisation.
Answer:
Charles Goodyear

Match the columns:

Question 1.

Column ‘A’	Column ‘B’
1. Jute	a. Animal origin
2. Air	b. Plant origin
3. Leather	c. Man-made
4. Cement	d. Abiotic

Answer:

Column ‘A’	Column ‘B’
1. Jute	b. Plant origin
2. Air	d. Abiotic
3. Leather	a. Animal origin
4. Cement	c. Man-made

State whether the following statements are ‘true’ or ‘false’.

Question 1.
We can find plastic in nature.
Answer:
False

Question 2.
Soap is a man-made substance.
Answer:
True

Question 3.
We should reuse available resources.
Answer:
True

Question 4.
Nylon clothes are good summer wear.
Answer:
False

Question 5.
Glass is a man-made substance.
Answer:
True

Question 6.
In irreversible changes original substances can be obtained again.
Answer:
False

Question 7.
Rayon is made up of cotton and wood pulp.
Answer:
True

Give two examples of each of the following:

Question 1.
Natural fibres
Answer:
cotton, silk

Question 2.
Synthetic fibres
Answer:
terylene, rayon

Question 3.
Biotic natural substances
Answer:
wool, jute

Question 4.
Abiotic natural substances
Answer:
air, water

Question 5.
Man-made substances.
Answer:
paper, glass

Classify the following substances in the table given below.
(iron, wood, brick, paper, terylene, stone, jute, air, silk, utensils, plastic, rayon, water, wool, dacron, lac, nylon, pearl)
Answer:

Natural Substances	Man-made Substances Natural Fibres		Synthetic Fibres
iron, wood, stone, water, lac, pearl	brick, paper, utensils, plastic	jute, silk, wool	terylene, rayon, dacron, nylon

Define:

Question 1.
Natural substances.
Answer:
Substances available in nature are called natural substances.

Question 2.
Man-made substances.
Answer:
Man-made substances are new substances produced by processing naturally available resources.

Question 3.
Biotic substances.
Answer:
Natural substances obtained from living things are called biotic substances.

Question 4.
Abiotic substances.
Answer:
Natural substances that are not obtained from living things are called abiotic substances.

Question 5.
Plant-originated substance.
Answer:
A substance obtained from a plant is called a plant-originated substance.

Question 6.
Animal-originated substance.
Answer:
A substances obtained from an animal is called an animal-originated substance.

Question 7.
Hydrocarbons.
Answer:
Substances obtained from mineral oil are called hydrocarbons.

Answer the following in one or two sentences.

Question 1.
Why was Rayon named so?
Answer:
The threads of Rayon have shine and strength. They appeared to be shining bright like the sun’s rays. Hence, they were named ‘Rayon.

Question 2.
How are TV sets, refrigerators, etc. packed? Why?
Answer:
To pack TV sets, refrigerators, etc. big cartons and thermocol are used. These man-made substances are water resistant, light weight and easy for transportation.

Question 3.
Give the properties and uses of nylon.
Answer:
Nylon threads have a shine and are strong, transparent and water resistant. They are used to manufacture clothes, fishing nets, ropes, etc.

Question 4.
What is latex?
Answer:
Latex is a milky white natural substance produced in the stems of rubber trees.

Question 5.
Name the basic material used to obtain paper.
Answer:
Wood is the basic material used in the manufacture of paper.

Question 6.
What kind of paper is used for currency notes manufacturing?
Answer:
Flax fibre is used in the manufacture of currency notes.

Question 7.
Where was the process of making paper invented?
Answer:
The process of making paper was invented in China.

Answer in brief:

Question 1.
What are the advantages of synthetic fibre?
Answer:
Advantages of synthetic fibre are:

These fibres can be manufactured on a large scale.
They cost less.
They are strong and durable.
They can be used for a long time.
They are water repellent. They dyy easily.
They are light weight and comfortable to wear.
Clothes made from these threads are wrinkle free and scratch free.

Question 2.
Give the shortcomings of synthetic fibre.
Answer:

They are water repellent. Hence, they do not absorb sweat from the skin.
Continuous use of these clothes keeps the skin moist which may cause skin diseases.
Synthetic clothes are uncomfortable to wear especially in summer.
They catch fire easily.
If they catch fire, they stick to the skin and cause skin injuries.
These fibres are not decomposed by micro-organisms.

Question 3.
Write a short note on natural rubber.
Answer:

Rubber is a natural substance obtained by collecting the latex of certain trees.
The botanical name of this tree is ‘Hevea brasiliensis’
In India, the maximum production of rubber is in Kerala.

Question 4.
What are dacron, terylene and terene?
Answer:

Dacron, terelyne and terene are synthetic fibres prepared from hydrocarbons.
Various hydrocarbons obtained from mineral oil are used to make polymer chains.
A solution of such polymer is pressed through a strainer with fine holes.
The fibre formed after cooling are long and unbroken threads.
These threads have been named as dacron, terylene and terene.

Give scientific reasons:

Question 1.
Natural substances are depleting.
Answer:

Due to increase in population there is an increase in demand. To meet this demand, natural substances are used to a greater extent.
Due to human nature to make his life more comfortable, he learnt to use natural resources and also began to process them to make new substances. Hence natural substances are depleting at an alarming rate.

Can you tell?

Question 1.
Difference between leather, jute, wool, cotton and soil, water, metals.
Answer:

Leather, jute, wool are biotic natural substances.
Soil, water, metals are abiotic natural substances.

Question 2.
How are leather and wool different from jute and cotton?
Answer:
Leather and wool are obtained from animals while jute and cotton are obtained from plants.

Question 3.
Do you find plastic, nylon, brass or cement in nature?
Answer:
No, they are all man-made materials.

Question 4.
Can red chillies become green chillies again?
Answer:
No, the change from green chillies to red chillies is irreversible.

Question 5.
From which substances in nature can we get threads or fibre?
Answer:
Cotton plant, jute, silkworm.

Question 6.
What are clothes made from?
Answer:
Clothes are made from yarn obtained from fibre.

Classify the following substances according to their uses:
sand, soap, wool, window glass, bamboo, cotton, bricks, silk, leafy vegetables, cement, fruits, water, sugar.
Answer:

For construction: Sand, window glass, bamboo, bricks, cement.
As food: Leafy vegetables, fruits, water, sugar.
At home: Soap for cleaning.
For clothes: Wool, cotton, silk.

Make a list of objects, each of which can be made from several substances.
Answer:

Objects	Substances
Table	Wood, glass, plastic.
Toys	Wood, plastic, clay.
Utensils	Aluminium, wood, glass, ceramic, plastic.

Use your brain power!

Question 1.
Complete the table below, showing how substance of daily use are classified.

Answer:

Natural
Biotic
Cement
Animal Origin
Cotton

6th Std Science Questions And Answers:

Ecosystems Class 8 Science Chapter 18 Questions And Answers Maharashtra Board

January 4, 2025January 3, 2025 by Bhagya

Balbharti Maharashtra State Board Class 8 Science Solutions Chapter 18 Ecosystems Notes, Textbook Exercise Important Questions and Answers.

Std 8 Science Chapter 18 Ecosystems Question Answer Maharashtra Board

Class 8 Science Chapter 18 Ecosystems Question Answer Maharashtra Board

1. Complete the following by using the correct option:

Question a.
Air, water, minerals, soil are ………….. factors of an ecosystem. (physical, organic, inorganic)
Answer:
Air, water, minerals, soil are physical factors of an ecosystem.

Question b.
River, ponds, ocean are …………. ecosystems, (land, aquatic, synthetic)
Answer:
River, ponds, ocean are aquatic ecosystems.

Question c.
Man is ………….. in an ecosystem. (producer, consumer, decomposer)
Answer:
Man is consumer in an ecosystem.

2. Match the following:

Question a.

Producer	Ecosystem
1. Cactus	a. Forest
2. Aquatic plants	b. Creek
3. Mangroves	c. Aquatic
4. Pine	d. Desert

Answer:

Producer	Ecosystem
1. Cactus	d. Desert
2. Aquatic plants	c. Aquatic
3. Mangroves	b. Creek
4. Pine	a. Forest

3. Give my information:

Question a.
Ecosystem.
Answer:
Ecosystem is the structure formed by the interrelationships between the living organisms and non-living components in their surrounding habitats. Living organisms are also called biotic factors while the non-living components are called abiotic factors. The abiotic and biotic factors have a reciprocal relationship with each other. The ecosystem has plants as producers, animals as consumers and microbes as decomposers.

The decomposers return the substances back to the nature by process of decomposition in which the organic complex molecules are reduced to their inorganic constituents. Thus the dead remains of plants and animals are once again recycled back to the nature in any healthy ecosystem.

Question b.
Biome.
Answer:
Biomes are a larger collection of small ecosystems which are similar in their structure. In a particular biome there are same climatic, abiotic factors and similar living organisms. Biomes are of two main types, land biomes and aquatic biomes. The land biomes exist only on land. Land biomes are of following subtypes based on the abiotic factors. E.g. Grasslands, evergreen forests, deserts, Tundra ecosystem, ecosystems in Taiga, tropical rainforests, etc. Aquatic biomes include freshwater ecosystem, marine ecosystem and brackish water ecosystem found in the creeks.

Question c.
Food web.
Answer:
The complex feeding relationships form a food web. In nature in any ecosystem, the food chains are not straight and linear. But these are quite complex. A prey is consumed by a predator but this predator can itself be a prey to some other predator. E.g. Frog is a predator for variety of insects but frog is preyed upon by snake and the snake can be eaten by a bird. The same bird can also feed on insects or frog. The interrelationships between different biotic components of any ecosystem thus form the complicated food web.

4. Give scientific reasons:

Question a.
Plants in an ecosystem are called producers.
Answer:
are cut down causing deforestation. The wild animals lose their habitat. Many of them become extinct. There is great loss of flora and fauna due to construction of large dams. There is undue pressure on the land surface caused due to stored water column. This may cause earthquakes. The human settlements are removed as their houses and farms are immersed under water. In all the above ways large dams destroy the ecosystems.

Question b.
Large dams destroy ecosystems.
Answer:
When a large dam is constructed, the original landscape is changed. The trees are cut down causing deforestation. The wild animals lose their habitat. Many of them become extinct. There is great loss of flora and fauna due to construction of large dams. There is undue pressure on the land surface caused due to stored water column. This may cause earthquakes. The human settlements are removed as their houses and farms are immersed under water. In all the above ways large dams destroy the ecosystems.

Question c.
Rhinos were restored in Dudhwa forest.
Answer:
Long ago in last century, Dudhwa forest was the natural habitat of the one-horned Rhino. However, due to hunting and poaching, the Rhino became almost extinct. In order to restore it back the breeding in captivity was attempted and the young ones were released in the natural habitat. Saving the precious wildlife is important and hence these efforts were done.

5. Answer the following:

Question a.
What are the effects of increased population (of human beings) on ecosystems?
Answer:

Human population growth rate is very big as compared to other animals.
Moreover, they are apex consumers in an ecosystem. Just like any other organisms, ecosystems provide all the basic needs to humans, too.
However, man demands much more due to excessive population. The natural resources are utilized on the large scale only by man.
Changing lifestyles, consumerism, degradation of nature and pollution are certain aspects which are created only by human beings.
All these cause increased stress on the ecosystems. Large human population also produces large-scale solid wastes.

Question b.
How is urbanization responsible for destruction of ecosystems?
Answer:
When people do not get sufficient food and other amenities, they migrate to the cities. The cities provide employment for many people due to industries, factories and other facilities. Every day many people migrate to cities. This causes urbanization. Due to increased population in cities, there is more need for housing. This results in loss of agricultural lands, marshlands, wetlands, forests and grasslands, etc.

The natural ecosystems are lost in an attempt to have developmental work. Human interference causes changes in the ecosystems. When land usage is changed many naturally occurring species of plants and animals are exterminated. Animal- human conflicts are very common in newly established urban areas which are near the natural forests.

Question c.
What are the reasons for war?
Answer:
There are difference of opinions and competition over land, water, mineral resources, etc. among neighbouring countries. Moreover, there can be economic and political causes which lead to war among different countries. Many times the l religions and ethnicity are also caused for dispute. Due to international conflicts, the peace is disturbed and it results in war.

Question d.
Explain the interactions among the factors of an ecosystem.
Answer:

The abiotic factors such as air, water, soil, sunlight, temperature, humidity, etc. affect the biotic factors, i.e. the surviving plants, animals and microbes in the ecosystem.
The type of abiotic factors in an ecosystem determine the survival of biotic factors. The population of these biotic factors is also dependent on the quality of abiotic factors.
The proportion of abiotic factors in an ecosystem fluctuates as biotic factors use up or release particular abiotic factors.
Every biotic factor also interacts with its necessary abiotic factors as well as other biotic factors around it.

Question e.
Differentiate between evergreen forests and grasslands.
Answer:

Evergreen forests	Grasslands
1. About seven percent of the Earth’s surface is occupied by evergreen forests.	1. About 30 percent of the Earth’s surface is covered by grasslands.
2. More than half of the earth’s terrestrial plants and animals are seen in evergreen forests.	2. Grazing animals are seen in grasslands.
3. Tropical evergreen forests are dense, multi-layered.	3. Grasslands consist of tall grass. There are wild grasses and there may be some trees.
4. These forests are found in the areas receiving more than 200 cm annual rainfall i.e. very heavy rainfall.	4. There is an average of 20 – 35 inches of rainfall a year in grasslands.
5. Tropical regions show evergreen forests.	5. Several parts of the world have grasslands.

6. Describe the following pictures:

Question a.
Describe the following pictures

Answer:
The picture no. 1 is showing desert ecosystem, while the picture no. 2 is showing a forest ecosystem where a wetland (a lake) is also shown. In desert ecosystem, the producers are green cactus and a palm tree. Since in desert there are scanty rains, the vegetation is very less. The soil is sandy soil. The consumers of the desert are also limited.

In the above picture camel is shown which is a primary consumer in the desert ecosystem. Camel is very well adapted for desert life. There is also the scarcity of water in desert and hence cactus shows xerophytic (suitable to survive in desert) adaptations.

In second picture, the forest ecosystem is shown because we can see elephant and tiger in the picture. Also, giant hornbill is sitting on the tree. This forest must be tropical evergreen forest. The rainfall is heavy in such areas and hence different types of wetlands can be seen in forests. Wetlands support variety of life. A separate aquatic ecosystem does exist here which is closely interconnected with the terrestrial ecosystems through food chains and food web.

The birds utilize the fish as their prey. The wild animals come to wetlands to quench their thirst. In this picture the plants, grass, etc. are producers, small fishes in the lake are primary consumers. They will be eaten by larger fishes which are secondary consumer in the aquatic ecosystem. The elephant is herbivorous animal and hence it is primary consumer. Snake is the secondary consumer while the birds of prey (eagle that is flying) and tiger are tertiary consumers.

Can you recall?

Question 1.
Which factors do you find in your surroundings?
Answer:
In our surroundings there are abiotic and biotic factors. The biotic factors are animals and plants in the surroundings. The invisible bacteria and fungi also have important role in the ecosystem as decomposers. Important abiotic factors are air, water, land, sunlight, etc.

Question 2.
Are these factors directly or indirectly related to you?
Answer:
We are directly or indirectly connected to every single factor in the surrounding in which we reside. For the requirement of food, we are dependent on plants and animals. For our survival we continuously need oxygen, water and other minerals, etc.

Classify:

Question 1.
Classify the following into living and non-living factors. Sunlight, Sunflower, Elephant, Lotus, Algae, Stone, Grass, Water, Ant, Soil, Cat, Fern, Air, Lion.
Answer:

Living Factors	Non-living Factors
Sunflower, Elephant, Lotus, Algae, Grass, Ant, Cat, Fern, Air, Lion.	Sunlight, Stone, Water, Soil, Air.

Can you tell?

Question 1.
What is the role of microbes in above interaction?
Answer:
Microbes play the role of decomposers in the above interactions.

Question 2.
How do producers obtain abiotic factors?
Answer:
Producers obtain solar energy from sunlight. The other nutrients are obtained from soil, water and air.

Question 3.
From where do the consumers get their food?
Answer:
Consumers get their food from producers and other consumers.

Project:

Question 1.
Visit an ecosystem nearby, List the biotic and abiotic factors in it. Show with pictures or sketches, how they are dependant on each other.

Question 2.
With the help of internet find out the loss of ecosystems due to wars or atomic explosions. Describe in your words.

Class 8 Science Chapter 18 Ecosystems Important Questions and Answers

Complete the following by using the correct option:

Question 1.
Biotic community is another name for ………. (ecology, ecosystem, population)
Answer:
Biotic community is another name Biotic for ecosystem.

Question 2.
Microbes in an ecosystem are ………… (producers, consumers, decomposers)
Answer:
Microbes in an ecosystem are decomposers.

Question 3.
Many types of ecosystems are found in ………… (oceans, deserts, biosphere)
Answer:
Many types of ecosystems are found in biosphere.

Question 4.
………….. is a type of grassland ecosystem. (Taiga, Tundra, Desert)
Answer:
Taiga is a type of grassland ecosystem.

Question 5.
Gir forest in Gujarat is the only habitat/shelter for the spectacular ………….. (Asiatic lion, Royal Bengal tiger, One-horned rhino)
Answer:
Gir forest in Gujarat is the only habitat shelter for the spectacular Asiatic lion.

Correct the following statements by changing one or two words:

Question 1.
Primary, secondary, tertiary consumers are the abiotic factors of the ecosystem.
Answer:
Primary, secondary, tertiary consumers are the biotic factors of the ecosystem.

Question 2.
Most of the ecosystems are simple.
Answer:
Most of the ecosystems are complex.

Question 3.
The word ecosystem was brought in the use by Ray Claffam.
Answer:
The word ecosystem was brought in the use by A.G. Tansle.

Question 4.
Specific ecosystem developed in a vast area is called a biosphere.
Answer:
Specific ecosystem developed in a vast area is called a biomes.

Question 5.
Longer summer and limited rain develop very tall plants in the grassland ecosystem.
Answer:
Longer summer and limited rain develop dwarf plants in the grassland ecosystem.

Question 6.
29 % of the earth surface is covered by water and only 71 % has land on it.
Answer:
71 % of the earth surface is covered by water and only 29 % has land on it.

Question 7.
Dams increase the water current in lower area.
Answer:
Dams lessen the water current in lower area.

Match the following:

Question 1.

Column ‘A’	Column ‘B’
1. The Great Himalayan National Park	a. Asiatic lion
2. Kaziranga	b. Tigers
3. Bharatpur	c. Aquatic birds
4. Ranthambore	d. One-horned Rhino
5. Gir forest	e. White panther

Answer:

Column ‘A’	Column ‘B’
1. The Great Himalayan National Park	e. White panther
2. Kaziranga	d. One-horned Rhino
3. Bharatpur	c. Aquatic birds
4. Ranthambore	b. Tigers
5. Gir forest	a. Asiatic lion

Find the odd one out:

Question 1.
Typha, Pistia, Eichhornia, Dipterocarpus
Answer:
Dipterocarpus. (All others are aquatic plants.)

Question 2.
Teak, Parthenium, Pine, Sandalwood
Answer:
Parthenium. (All others are forest trees.)

Question 3.
Giraffe, Zebra, Cheetah, Elephant
Answer:
Cheetah.. (All others are surviving grassland animals, Cheetah is a forest animal that is extinct from Asia.)

Question 4.
Hyena, Cow, Deer, Rabbit
Answer:
Hyena. (All others are primary consumers, Hyena is tertiary consumer.)

Question 5.
Fusarium, Leptocorsia, Aspergillus, Polycarpus
Answer:
Leptocorsia. (All others are decomposers, Leptocorsia is primary consumer.)

Taking into consideration the relationship in the first pair, complete the second pair :

Question 1.
Plants : Producers : : ……… : Consumers
Answer:
Animals

Question 2.
Secondary consumers : Jackals : : Tertiary consumer : ………..
Answer:
Kite/Lion/Hyena

Question 3.
Goat, sheep : Grassland ecosystem : : Tigers : …………..
Answer:
Forest ecosystem

Question 4.
Desert : Land biome : : Creek : …………….
Answer:
Aquatic biome

Question 5.
Limited rain : Grassland ecosystem : : ……….. : Tropical rainforests
Answer:
Excessive rain.

Answer in one sentence:

Question 1.
What is an ecosystem?
Answer:
The structure which is formed due to interactions between abiotic and biotic factors is called an ecosystem.

Question 2.
What is an ecological niche?
Answer:
The position of any living organism with reference to other living organisms and the role played by that organism is called ecological niche.

Question 3.
How are types of ecosystems formed?
Answer:
Types of ecosystems are formed according to size, place, climate, types of plants and animals that survive in that ecosystem.

Question 4.
Give examples of land biomes.
Answer:
Grasslands, evergreen forests, deserts, Tundra or polar ecosystem, ecosystems in Taiga, tropical rainforests, etc. are land biomes.

Question 5.
What are the reasons for tourism among the people?
Answer:
Tourism is mainly because people like to visit scenic places, undertake nature watch, wish to visit to sacred places and for entertainment purpose.

Question 6.
Why we should protect natural ecosystems?
Answer:
Natural ecosystems must be protected as they maintain balance in the biosphere.

Give my information Write short notes:

Question 1.
Dudhwa forest.
Answer:
Dudhwa forest is in Uttar Pradesh. About a century back, Dudhwa forest was the habitat for one-horned Rhino. However, due to hunting and poaching in 20th century, this animal became endangered. Thus to restore their populations, on 1st April 1984 rhino were introduced there again. Rhinos can were bred in captivity followed by releasing them back into natural ecosystem.

For this purpose at first the land was selected. This was 27 square km grassland and forest with continuous water supply through natural resources. Two observatories were established for making these efforts successful. Now Dudhwa is known for one¬horned Rhino population.

Question 2.
Aquatic ecosystems.
Answer:
Earth’s 71 % of surface is covered over by aquatic ecosystems. They are of three main types, viz. fresh water ecosystem, marine ecosystem and brackish water ecosystem. Rivers, lakes and ponds and streams are some of the fresh water ecosystem. Fresh water contains less salt and hence it is potable. Marine water has more salinity, i.e. its salt content is high. Brackish water ecosystem is present in the creeks. Here the saline and fresh water mix together. Hence salinity here is lesser than that of the marine water.

Give scientific reasons:

Question 1.
Microbes are called decomposers.
Answer:
Decomposition is the process in which the organic compounds are broken down to their inorganic constituents. The organic substances such as carbohydrates, proteins and lipids which are locked in the dead remains of plants and animals are converted into hydrogen, oxygen, calcium, iron, sodium, potassium, etc. by microbes. Therefore, microbes are called decomposers.

Use your brain power:

Question 1.
Which biotic factors get affected due to a dam?
Answer:
The biotic factors include plants, animals and humans. Lot of vegetation is submerged from the place where dam is constructed. The forests are wiped out. Large scale deforestation takes place in the proposed dam area. Wildlife is destroyed completely. The resident animals whose habitat are there either migrate away or are killed due to lack of their food and shelter. Many instances of animal-human conflicts arise when the wild animals drift to the neighbouring human settlements.

If human settlements are shifted, people are displaced. They lose their houses and agricultural land. Though compensation is given to them, there is great change for the people. Water current in lower area of the dam is reduced due to construction of dam-walls. Therefore, the original lotic (running 5 water) ecosystems that were present are destroyed after the construction of dam.

Question 2.
What will be the effects on biotic factors in the running water of river?
Answer:
The aquatic flora (plants) and fauna (animals) are well adapted to their habitats. The running water ecosystems are known as lotic ecosystems. The non-moving waters on the contrary create lentic ecosystems. Lotic ecosystems provide special adaptations to the plants and animals living therein. Plants are mostly in the form of freely floating algae and phytoplankton. Animals are well adapted for swimming in the currents of water. The fishes especially show a stream-lined body, fins for swimming, and gills to take up dissolved oxygen in the water. The other animals are also well adapted to the currents of water.

Think about it:

Question 1.
Can we call a tree an independent ecosystem?
Answer:
The huge tree can be an independent ecosystem. On one such tree there may be different habitats. Variety of insects thrive on huge tree by making their habitats in cracks and crevices on the tree. Many birds visit the tree to feed on such insects. There are many bird species that live in the hollow of the tree. Garden lizards, chameleons, snakes are the different reptiles seen associated with the tree ecosystem.

Squirrels, rabbits, bats are the mammals which take shelter in and around the trees, also inhabit a tree variety of fungi, lichens, mosses and epiphytic plants like orchids survive on the huge trees. Many food chains and complicated food webs are formed with the support of the tree. Thus one can say that a tree is an independent ecosystem.

Question 2.
Today Divija visited a hill. Honey: bees were hovering on flowers. One of them stung Divijia’s hand. Divija was hurt due to that sting and said with anger that all the honey-bees from the whole world must get destroyed. Afterwards, she thought what will happen if all honey-bees are destroyed? We will get honey, nothing more. What would be your explanation to Divija?
Answer:
Honey bees provide us with honey and bee-wax. Both of these are commercial products. But more than that the role played by honey bees in the pollination of flowers is very important. Due to their nectar collecting behaviour, they bring about pollination of the flowers.

Presence of honey bees is thus very essential for the agriculture and horticulture. Without honey bees, the growth of fruits and grains will not be possible, if pollination and subsequent fertilization does not take place in nature. This will create famine-like conditions. Therefore, honey bees’ position in the nature is very important.

Chart based questions:

Question 1.
Complete the following chart in context to a grassland.

Answer:

Question 2.
Write the information about various components of forest.

Answer:

Question 3.
Observe such ecosystems around you and complete the following chart.

Answer:

Question 4.
Complete the table.

Answer:

National Park/Sanctuary	State
1. Gir	Gujarat
2. Dachigam	Jammu-Kashmir
3. Ranthambore	Rajasthan
4. Dajipur	Maharashtra
5. Kaziranga	Assam
6. Sunderbans	Bengal
7. Melghat	Maharashtra
8. Periyar	Kerala

Question 5.
Complete the following chart:

Answer:

Diagram based questions:

Question 1.
Correct the following diagram:

Answer:

MCQs based on experiment:

Question 1.
Which one out of the following is not biotic factor?
(a) Humidity
(b) Rabbit
(c) Snake
(d) Bacteria
Answer:
(a) Humidity

Question 2.
Which climatic factor is causing migration of the birds in certain regions of the earth?
(a) Humidity and rainfall
(b) Ambient temperature
(c) Amount of carbon dioxide
(d) Amount of plant matter
Answer:
(b) Ambient temperature

Question 3.
Which abiotic factor mainly distinguishes marine water from the fresh water?
(a) Temperature
(b) Dissolved oxygen:
(c) Salinity
(d) Surface tension
Answer:
(c) Salinity

Question 4.
Why is creek water different from the river water?
(a) Creek water is more polluted than the river water.
(b) Creek water is less salty than the river water.
(c) Creek water is more saline than the river water.
(d) Creek water is less turbulent than the river water.
Answer:
(b) Creek water is less salty than the river water.

Question 5.
Which land biome shows presence of cacti plants more?
(a) Polar regions
(b) Grasslands
(c) Rainforest
(d) Desert
Answer:
(d) Desert

Projects:

Collect information

Question 1.
What are the possible threats to grasslands?
Answer:
Man tries to use grasslands for agricultural purpose. This transformation causes loss of natural ecosystem. Many animals from grasslands are killed by hunting and poaching. Though now Wildlife Act has protected these animals, many wildlife species are already extinct. There are chances of forest fires which is the greatest threat to grasslands. The global warming may also cause grasslands to become a desert.

Question 2.
Why did Asian Cheetah become extinct in last century?
Answer:
When British ruled India, Asian Cheetah was hunted to a great extent. The kings and British rulers did rampant hunting. The forest lands were also reduced due to encroachment by humans to build their settlements. Dams were constructed. Mega highways, bridges and roads caused loss of habitat for Asian Cheetah. Cheetah needs large thickly forested territory. This was lost due to all man-made activities. All these reasons made Asian Cheetah extinct in last century.

Question 3.
Observe Asian Cheetah on internet. Describe it.
Answer:
Cheetah is the fastest running feline animal on the earth. Though from Asian regions it is said to be extinct, in African grasslands, its occurrence is still there. But it is endangered animal. By 2016, the global cheetah population is estimated at approximately 7,100 individuals in the wild. Several African countries have taken steps to improve cheetah conservation measures.

Cheetah has a slender body, deep chest, spotted coat. Its head is small rounded and on the face there is black tear-like streaks. It has long thin legs and a long spotted tail. Cheetah in India were tamed during Moghul period for assisting in hunting. Stories about such episodes are commonly told. However, the last Cheetah in India was spotted in Bastar, M.P. in 1948.

8th Std Science Questions And Answers:

Natural Resources Class 7 Science Chapter 16 Questions And Answers Maharashtra Board

January 4, 2025January 3, 2025 by Bhagya

Balbharti Maharashtra State Board Class 7 Science Solutions Chapter 16 Natural Resources Notes, Textbook Exercise Important Questions and Answers.

Std 7 Science Chapter 16 Natural Resources Question Answer Maharashtra Board

Class 7 Science Chapter 16 Natural Resources Question Answer Maharashtra Board

1. Describe natural resources with reference to the following 3 types:

Question a.
Mineral resources
Answer:
Mineral wealth has an important place among natural resources. The rocks on the earth are mainly made of minerals. These minerals can be obtained by mining. Minerals that contain a high proportion of metals are ores, (i) Minerals are formed from the magma in the earth’s crust and the lava from the eruption of volcanoes when they cool and get transformed into crystals e.g. magnetite, mica, (ii) Minerals get transformed from one form into another due to large changes in temperature and pressure e.g. Diamond, Graphite, (iii) There are 3 types of minerals according to their properties Non-metal minerals: e.g. mica, sulphur, potash, diamond.

Metals minerals: e.g. Iron, gold, silver, tin, bauxite, platinum.
Energy minerals: e.g. Coal, mineral oil, natural gas, diamond, ruby, sapphire, jade are used as gems.

Some important minerals and ores are Iron ore, manganese, bauxite, copper and mica.

Question b.
Forest resources
Answer:

A forest is a natural habitat of plants, animals and microbes.
Forest perform certain specific protective and productive functions.
We get different types of wood and many medicinal plants from forests.
Forest wealth includes fire wood, trees like teak, mahogany, neem, acacia, subabhul, fibers, paper, rubber, gum, aromatic substances.
We get fragrant essential oils from lemon grass, vanilla, kewada, vetiver (khus) and eucalyptus.
Sandalwood and oil of eucalyptus are used for making soaps, cosmetics and incense sticks.
Also we get fruits, bulbs, roots, honey, sealing wax, dyes from forest.
Many medicinal plants adulsa, bel, neem, periwinkle, cinnamon, are used for treatment of various diseases such as cough cold, malaria, diarrhoea, cancer, fever and cold.
Wood is used as a source of energy for cooking purpose and for keeping warm.
For making furniture, tool handles, matches, bridges, boats etc.
Bamboos are used for matting, flooring, basket, ropes, rafts, cots etc.
Bamboos, wood are used in the manufacture of rayon, yams, artificial silk-fibers.

Question c.
Ocean resources
Answer:

Oceans occupy about 70% of a earth’s surface.
Energy can be obtained on a large scale from oceans.
Sea waves at high and low tide and ocean currents are being used for generation of power.
There are billions of tons of minerals dissolved in ocean water.
There are large reserves of tin, chromium, potassium, phosphates, copper, zinc, iron, lead, thorium, manganese, sulphur, uranium in the ocean and sea beds.
Also we get many types of gems, conches, shells and pearls from the sea.
There are large reserves of mineral oil and natural gas at the bottom of sea.
We get fishes, dried shrimp, shells, fungi, shark, cod fish and sea cucumber from the ocean.

2. Write answers to the following questions in your own words.

Question a.
What is meant by fossil fuel? What are their types?
Answer:

Fossil fuels (such as coal or natural gas) are formed in the earth from dead plants and animals, due to high pressure from above and the heat from the earth’s interior.
The dead plants, animals get transformed into fossil fuel.
There are three types of fossil fuels which can be used for energy production, Coal, oil and natural gas.

a. Coal:

Coal is a solid fossil fuel formed over millions of years by the decay of land vegetation,
Coal is a store house of carbon. Coal is found in mines,
It is like porous, hard, black rock.
It is burnt to obtain heat energy.
It is used as a fuel in thermal power plants and to run boilers and railway engines, for cooking and baking bricks.
Anthracite is the coal of the highest grade.
Producer gas and water gas are obtained from coal.

b. Mineral oil:

Mineral oil is the liquid fuel formed by the decomposition of organic substances buried underground,
The underground mineral oil is extracted through oil wells.
Mineral oil is found mainly in oil sands, shale, sandstone and limestone at a depth of about 1000 to 3000 metres.
Mineral oil is also known as petroleum or crude oil. It is greenish-brown in colour.
Petroleum is a mixture of many compounds mainly of the hydrocarbon type.
It also contains compounds of oxygen, nitrogen and sulphur.
Petroleum is extracted through oil wells and refined by fractional distillation to separate other components,
Aviation petrol, gasoline, diesel, kerosene, naphtha, lubricating oil, tar are all obtained from petroleum.
They are used as fuel and for production of dyes, pesticides, perfumes and artificial fibres.

c. Natural gas:

Natural gas is an important fossil fuel.
It is lighter than air. It is found with petroleum in underground oil wells and in some places as natural gas alone.
The main component of natural gas is methane (CH₄), ethane (C₂H₆), propane (C₃H₈) and butane (C₄H₁₀) are present in small proportions.
This gas is highly flammable.
This fuel can be carried over long distance by means of a gas pipeline.
In absence of pipeline, it is transformed under high pressure into compressed natural gas (CNG) and liquefied natural gas (LNG).

Question b.
Make a list of the components we obtain from mineral oil.
Answer:

Mineral oil is the liquid fuel. It is also known as petroleum or crude oil. Petroleum is refined by fractional distillation to separate other components.
Aviation petrol, gasoline, diesel, kerosene, naphtha, lubricating oil, tar are the components we obtain from mineral oil.

Question c.
What do we get from forest?
Answer:

A forest is a natural habitat of plants, animals and microbes. We get wood, firewood from trees like teak, mahogany, neem, subabhul.
Also we get fibers, paper, rubber, gum and aromatic substances.
We get many medicinal plants like Adulsa, Bel, Neem, Periwinkle, Cinnamon, Cinchona which are used for treatment of various diseases like cough, cold, diarrhea, fever, cancer, diarrhoea, nausea, malaria.
We get fragrant essential oils from lemon grass, vanilla, kewada, khus, eucalyptus.
In addition to this we get fruits, bulbs and roots, honey, sealing wax, catechu, dyes from forest.

Question d.
What are the items included in ocean resources? What are their uses?
Answer:

Tons of minerals are found in ocean water.
They are tin, chromium, phosphates, copper, zinc, iron, lead, manganese, sulphur, uranium etc.
We also get many types of gems, conches, shells and pearls from the sea.
Mineral oil and natural gas is found at the bottom of sea.

Bio-resources in oceans

Fishes – like pomfret, seer fish as also shrimps
prawns – they are sources of proteins and vitamins, therefore, mainly used as sea food
Dried shrimp, Bombay duck powder – used as poultry feed and is a good manure.
Shells – used for preparation of medicines, ornaments and decorative articles.
Fungi – used for the production of antibiotics.
shark and cod fish – used for producing edible oil rich in Vitamins A, D and E.
Sea cucumbers – used as medicine for treating cancer and tumours.

Mineral resources from oceans

Thorium – used in the production of atomic energy.
Magnesium – used in the flash bulb of a camera.
Potassium – the main ingredient in production of soap, glass, fertilizer.
Sodium – used in the production of cloth and paper.
Sulphate – used in making artificial silk.

Question e.
Why should we prevent the wastage of fuels used for vehicles?
Answer:

Vehicles are powered by gasoline or diesel petrol.
Nowadays compressed natural gas (CNG) is also used.
Aviation petrol, gasoline, diesel, we get from petroleum after fractional distillation.
Petroleum is a non-renewable source of energy.
It is getting depleted day by day and the demand for fuel has increased greatly due to the rapidly growing population.
But the reserves of petroleum (fossil fuel) are limited.
It is becoming difficult to meet the increased demand. So we should prevent the wastage of fuel.

Question f.
Why is the diversity of plants and animals in the forests declining?
Answer:

The major causes of biodiversity decline are land use changes, pollution, changes in atmosphere, CO₂concentration, changes in the nitrogen cycle, acid rain, climate alteration and introduction of exotic species.
All this is due to population growth.
This is the main cause of the loss of biodiversity. More of wood for fuel is been used, more land is required for food production, livestock grazing etc.
Rainforest land is converted to industrial and residential usage, so natural habitat of birds, animals is destroyed.
Due to population growth most of wild land is converted to crop land. So no space for animals to live, their natural habitat is destroyed.

Question g.
Write the names of five minerals and the useful substances obtained from them.
Answer:
Some important minerals and ores are:

Iron ore: It is used for making farming implements, rails of railway tracks etc.
Manganese: Compounds of manganese are used in the preparation of medicines and for giving a pink tinge to glass. Manganese is also used in electrical appliances.
Bauxite: It contains 55% Aluminium. Therefore, it is used mainly in aeroplanes, transport vehicles and to make electric wire.
Copper: It is used to make electric wires as well as in radios, telephones, vehicles, and for making kitchen utensils and statues.
Mica: Mica has many uses such as in ayurvedic medicines, dyes, electric machines and equipment, wireless communication equipment, etc.

Question h.
Name the two important stages in the process of obtaining metals from ores.
Answer:
The two important stages in the process of obtaining metals from ores are extraction and purification.

3. What steps are taken for protection and conservation of natural resources?

Question a
What steps are taken for protection and conservation of natural resources?
Answer:

Protection and conservation of natural resources is necessary to protect the natural world. (CNRM) Community Natural Resource Management has been promoted in recent years for biological conservation.
The World Conservation Union has been formed. It is the world’s leading authority and democratic platform in conservation and sustainability.
Young trees should not be cut. More and more trees need to be grown.
The stringent restrictions/ laws/ Regulations regarding use of forests should be strictly followed. Awareness is being created through Mass media.

4. Complete the Flow Chart:

Question a.

Answer:

5. How does the economic condition of a nation depend on its natural resources?

Question a.
How does the economic condition of a nation depend on its natural resources?
Answer:
1. Natural resources are a necessary condition for economic growth.
2. Three circles enclosed within one another shows how both economy and society are subsets of our planetary ecological system.

3. Natural resource economics deals with the supply, demand and allocation of the Earth’s natural resources.
4. Economic growth is an increase in the value of goods and services produced in an economy.
5. The natural resources of a country depend on the climatic and environmental conditions.
6. Countries having plenty of natural resources enjoy good growth than countries with small amount of natural resources.
7. A country having skilled and educated work force with rich natural resources takes the economy on the growth path, because skilled and educated people can efficiently utilize or exploit natural resources, e.g. Saudi Arabia: their economic growth is high, because they have oil wells.
8. All countries import fuel or oil from them so Saudi Arabia is economically a rich country.

6. Which medicinal plants will you grow on your school premises and near your house? Why?

Question a.
Which medicinal plants will you grow on your school premises and near your house? Why?
Answer:
1. I will grow tulsi, neem, lemon grass, bel, adulsa, periwinkle, cinnamon, ashwagandha, shatavari, amla, hirda, behda.
2. These plants are used for treatment of various diseases.

Tulsi → for cough and cold.
Amla, hirda, behda → Help in digestion of food or any stomach related problems.
Adulsa → for cough and cold
Bel → for Diarrhoea
Neem → Fever and cold
Periwinkle → Cancer
Cinnamon → Diarrhoea, nausea.
Cinchona → Malaria.
Ashwagandha → It can reduce blood sugar levels. It can reduce stress and anxiety, may reduce symptom of depression.
Shatavari → has been used for centuries in Ayurveda to support the reproductive system.
Amla → Excellent source of vitamin C. Amla juice is best tonic to keep you younger for long.
Hirda → This fruit is commonly called Haritaki. It is used for treating arthritis, dental problems like caries, bleeding gums.
Behda →(Beleric) is a rejuvenative and laxative, proves beneficial for hair, throat and eyes.
Tulsi → Tulsi has germicidal, fungicidal, anti-bacterial anti-biotic properties, cures fever. Treats diabetes, protects the heart. Tulsi has anti-oxidant component Eugenol which keeps one’s blood pressure under control.

Project:

Question 1.
Collect conches and shells of various shapes and colours and make a decorative article.

Question 2.
Collect information about the mines of various minerals.

Class 7 Science Chapter 16 Natural Resources Important Questions and Answers

Fill in the blanks:

Question 1.
………….. is the major raw material for biogas.
Answer:
cow dung

Question 2.
Atomic energy is obtained by using ores of ………….. .
Answer:
Uranium

Question 3.
Biogas generation is mainly based on the principle of ………….. .
Answer:
Fermentation

Question 4.
Floods can be prevented by ………….. .
Answer:
Afforestation

Question 5.
Coal, petroleum, natural gas are ………….. resources.
Answer:
non-renewable

Question 6.
The total percent of land of world under forest cover is ………….. .
Answer:
30%

Question 7.
A naturally occurring substance ………….. .
Answer:
minerals

Question 8.
Minerals that contain a high proportion of metal are called ………….. .
Answer:
ore

Question 9.
Coal, mineral oil and natural gas are ………….. .
Answer:
fossil fuel

Question 10.
Deposits of common salt are also found in the earth. This salt is called ………….. .
Answer:
rock salt

Question 11.
………….. is the liquid fuel formed by the decomposition of organic substances.
Answer:
Mineral oil

Question 12.
The underground mineral oil is extracted through ………….. .
Answer:
oil wells

Question 13.
Mineral oil is also known as ………….. or ………….. .
Answer:
petroleum, crude oil

Question 14.
………….. are the preserved remains of dead organisms in rock.
Answer:
Fossil

Question 15.
Coal can be formed from ………….. .
Answer:
Fossils

Question 16.
Impurities of sand and soil in ore are called ………….. .
Answer:
Gangue

Question 17.
Coal mainly contains ………….. .
Answer:
carbon

Question 18.
Petroleum is formed from ………….. .
Answer:
organisms in sea

Question 19.
Separation of various fractions of petroleum is called ………….. .
Answer:
Refining

Question 20.
We can obtain minerals from rocks by ………….. .
Answer:
mining

Question 21.
………….. is the most important ore of aluminium
Answer:
Bauxite

Question 22.
………….. is the coal of the highest grade.
Answer:
Anthracite

Question 23.
Metals are obtained from their ore by ………….. and ………….. .
Answer:
extraction, purification

Question 24.
………….. is the largest oil and gas research and production company in India.
Answer:
ONGC

Question 25.
Natural gas is transformed under high pressure into ………….. and ………….. .
Answer:
LNG and CNG

Question 26.
The main component of Natural gas is ………….. .
Answer:
Methane

Question 27.
………….. and ………….. are used for adding fragrance in soaps and incense sticks.
Answer:
Sandalwood and oil of Encalyptus

Question 28.
………….. is a natural herbal medicine for cough and cold.
Answer:
Adulsa

Answer the following:

Question 1.
What is meant by natural resources?
Answer:

We get many substances from nature.
They satisfy a variety of our daily needs. Soil, stones, minerals, air, water, plants and animals on the earth are all various kinds of natural resources.

Question 2.
What are alternative fuels?
Answer:
Hydrogen, biofuels, methanol or wood alcohol, ethanol or green alcohol are some of the alternative fuels.

Question 3.
What is meant by fuels?
Answer:

Fuel is a substance that is used in day-to-day life and burned to generate energy.
Fuels such as coal, wood, oil, gas provide energy when burned.
Fuels are found in solid, liquid or gaseous state.

Question 4.
Which natural resources do we use as fuels?
Answer:
We use coal, mineral oil and natural gas as fuels.

Question 5.
What is meant by forests?
Answer:
An extensive area of land covered by a variety of plants is called a forest. A forest is a natural habitat of plants, animals and microbes.

Question 6.
What are the uses of forests?
OR
Write short note on forest and its uses.
Answer:

A forest is a natural habitat of plants, animals and microbes.
Forest help improve and maintain the quality of environment.
Forest helps in prevention of soil-erosion, help to control floods, protects wild life, maintains the balance of atmospheric gases.
We get many medicinal plants from forest which help in treatment of various diseases.
Examples Adulsa, Bel, Neem, periwinkle, amla tulsi, cinnamon.
We also get wood, firewood from trees like teak, mahogani, neem, sababhul. Wood is useful for making furniture, farming implements, in construction work.
Forest wealth includes fibres, paper, rubber, gum and aromatic substances.
We get fragrant essential oils from lemon grass, vanilla, kewada and eucalyptus.
They are used for making soaps, cosmetics and incense sticks. We get various fruits, bulbs, roots, honey, sealing wax, catechu dyes etc. from forest.

Question 7.
Are minerals to be found in seas and on the seabed as they are found inside the earth?
Answer:
Yes, there are very large reserves of tin chromium, phosphates, copper, zinc, iron, lead, manganese, sulphur, uranium etc. in the ocean and seabed.

Question 8.
How is mineral oil formed?
Answer:

Mineral oil is the liquid fuel formed by the decomposition of organic substances buried underground.
Millions of years ago, bodies of dead sea organisms sank to the bottom of the sea.
Layers of soil and sand collected on them.
Due to high pressure and temperature the remains of the dead organisms were transformed into mineral oil.
The underground mineral oil is extracted through oil wells.

Use your brain power!

Question 1.
Why are all minerals not ores?
Answer:

Minerals that contain a high proportion of metal are called ores.
Majority of the metals occur in the form of compounds called ores.
But all minerals are not ores.
Few metals like gold, silver, copper, platinum and bismuth occur in free state in nature. So all minerals are not ores.

Question 2.
What is meant by metal mineral and non¬metal mineral?
Answer:

Metal-minerals contain metallic elements in their chemical formula. So they are called metal-minerals, for example, iron, copper, gold, silver etc.
They contain metal in raw form.
Non-metallic minerals do not contain metal elements in their inorganic chemical formula Example, Clay, Diamond, Dolomite, Gypsum, Mica, Quartz.

Question 3.
Why is mineral oil called ‘liquid gold’?
Answer:
Because of its high price and value and its economic need, the mineral oil is called liquid gold. It’s reserve is less and demand is more.

Question 4.
Why is coal called black gold?
Answer:

Coal is a storehouse of carbon. Coal is used as a fuel, in thermal power plants as well as to run boilers and railway engines.
It is used as a fuel for cooking and for baking bricks in kilns on a large scale.
The gaseous fuels, producer gas and water gas are obtained from coal.
Coal as an energy resource, contributes greatly to industrial development.
As coal is black in colour and worth a lot of money just like gold, it is called black gold.

Question 5.
What would happen if underground mineral resources are exhausted?
Answer:

Coal, petroleum and other mineral are all non-renewable sources of energy.
The reserve is less and demand is more. They would get exhausted one day.
If such a situation occurs, we will not get electricity.
All our household and industries depend on electricity.
Transportation and household items, and food items would become very costly.
The survival of human life will be ver\ difficult.

Question 6.
Why is natural gas an eco-friendly fuel?
Answer:

Natural gas is an important source of energy which is eco-friendly because of its low carbon dioxide emission.
When burned it produces 45% less CO₂ than coal, 30% less than oil, and about 15% less than wood.
It does not produce carbon monoxide, sulphur dioxide or airborne particles, all of which are harmful to human and animal health.
It is referred as the clean energy source and is fuel for the present century as it does not ‘ pollute the atmosphere or contribute to global warming.

Question 7.
What useful things will we have to do without if rubber is no longer available?
Answer:

Rubber has played a largely hidden role in global environment history for more than 150 years.
In industries, rubber is needed to connect and protect all moving parts of machines.
Native people used rubber for rubber boots.
Household uses rubber in everything viz dish washing gloves, toys, jar seals, tyres in vehicles.
Welcome mat at the door, Boots, raincoats, mattress cushions, earplugs, hot water bottles, surgical tubing and gloves, in labs, birth control device.
In schools rubber bands, erasers, mouse pads, key board, rolling chair wheels. Head phone pads, rubber stamps are useful items used in schools and offices.

Question 8.
What are the adverse effects of clearing of forest or cutting down trees?
Answer:

Clearing of forest is also called Deforestation.
Removal or cutting down of trees has resulted in damage to habitat, biodiversity loss and aridity.
If has adverse impacts on concentration of atmospheric carbon dioxide. (Trees use up carbon dioxide from the atmosphere for the process of photosynthesis.)
Deforestation is a main contributor to global warming. Major cause of enhanced greenhouse effect. Deforestation cause carbon dioxide to linger in the atmosphere.
Deforestation reduced the content of water in the soil and ground water and atmospheric moisture, because trees extract ground water through the roots and release it into the atmosphere.
When a part of forest is removed the trees no longer transpire this water, resulting in much drier climate.
Due to deforestation soil erosion and flooding, landslide problems occur.
Deforestation results in decline in biodiversity, on a natural global scale is known to cause the extinction of many species.
Forest is habitat for wild life, and many medicinal plants. If forests are removed it will affect wild life and also we will not get medicinal plants.

Find out:

Question 1.
How did the various ages of the prehistoric period get their names on the basis of the uses of metals.
Answer:
1. The three-age system in history archaeology, and physical anthropology is a methodological concept adopted during the 19th century by which artifacts and events of late prehistory and early history could be ordered into a recognizable chronology.

2. Initially developed by C. J. Thomson, director of the Royal Museum of Nordic Antiquities, Copenhagen – as a means to classify the museum’s collection according to whether the artifacts were made of stone, bronze or iron.

3. Depending-upon the use of stone, bronze, iron, that period was known as stone age, bronze age, and iron age, respectively.

Answer the following:

Question 1.
Write down the difference between Metal minerals and Non-metallic minerals.
Answer:

Metal minerals	Non-metallic minerals
1. Metal minerals contain metal in raw form.	1. Non-metallic minerals do not contain metal.
2. These metals are generally associated with igenous rocks.	2. These metals are generally associated with sedimentary rocks.
3. They are usually hard and have shine of their own.	3. They are not usually hard, have no shine of their own.
4. e.g. Iron, copper tine, bauxite.	4. e.g. Salt, coal, mica, clay.

Question 2.
Write down the different types of coal.
Answer:
Peat, lignite (brown coal), bituminous coal and anthracite are various types of coal.
Anthracite is the coal of the highest grade.

Question 3.
Write down the characteristics of Compressed Natural Gas.
Answer:
Characteristics of CNG:

Catches fire easily.
No solid waste remains after combustion.
Carbon dioxide and water are formed in small quantities.
Other pollutants are not produced.
Can be transported easily.
Combustion can be controlled easily.

Observe the pictures and answer the question.

Question a.
What is the process shown in the given picture?
Answer:
The process shown is formation of mineral oil and natural gas.

Question b.
Explain the process.
Answer:

Mineral oil is the liquid fuel formed by the decomposition of organic substances buried underground.
Millions of years ago, bodies of dead sea organisms sank to the bottom of the sea.
Layers of soil and sand collected on them.
Due to high pressure and temperature the remains of the dead organisms were transformed into mineral oil.
The underground mineral oil is extracted through oil wells.

Question c.
What are the gaseous substances formed in the above process?
Answer:
Natural gas is also formed along with mineral oil. It contains methane, ethane, propane and butane gases.

Question d.
When the products of the process is refined, what other components are produced?
Answer:
When mineral oil is refined by fractional distillation products produced are petrol, diesel, kerosene, naphtha lubricating oil, tar, etc.

7th Std Science Questions And Answers:

In the World of Stars Class 7 Science Chapter 20 Questions And Answers Maharashtra Board

January 4, 2025January 3, 2025 by Bhagya

Balbharti Maharashtra State Board Class 7 Science Solutions Chapter 20 In the World of Stars Notes, Textbook Exercise Important Questions and Answers.

Std 7 Science Chapter 20 In the World of Stars Question Answer Maharashtra Board

Class 7 Science Chapter 20 In the World of Stars Question Answer Maharashtra Board

1. Write the proper words in the blanks:
(meridian, horizon, twelve, nine, apparent, celestial, ecliptic)

Question a.
When seen from a great distance, the sky seems to be touching the ground along a circle. This circle is called the …………… .
Answer:
horizon

Question b.
The ………….. is used while defining the zodiac sign.
Answer:
meridian

Question c.
Classified according to seasons, one season will have ………… nakshatras.
Answer:
nine

Question d.
The rising of the sun in the east and its setting in the west is the ………. motion of the sun.
Answer:
apparent

2. A star rises at 8 pm. tonight. At what time will it rise after a month? Why?

Question a.
A star rises at 8 pm. tonight. At what time will it rise after a month? Why?
Answer:

Str s rise and set 4 minutes earlier every day. If star rises at 8 pm tonight, it will rise at 7:56 pm tomorrow.
It will rise at 5:24 pm after a month.
The sun and the moon are seen to move from the west to the east against the background of stars.
The sun moves through one degree every day and the moon through 12 to 13 degrees.
This happens due to the motion of the earth around the sun and the moon around the earth which affects the duration of the stars and shortens its time period.

3. What is meant by “The sun enters a nakshatra?” It is said that in the rainy season the sun enters the mrug nakshatra. What does it mean?

Question a.
What is meant by “The sun enters a nakshatra?” It is said that in the rainy season the sun enters the mrug nakshatra. What does it mean?
Answer:

When we look at the sun we see not only the sun but also constellation behind the sun.
The constellation cannot be seen in bright sunlight but it is indeed present behind the sun.
As the earth changes its position, a different constellation or zodiac sign or raashi appears behind the sun.
This is what we express when we say that the sun enters a particular zodiac sign or raashi.
In rainy season due to the perceived motion of the sun, it enters mrug nakshatra and that is how it is expressed.

4. Answer the following questions.

Question a.
What is a constellation?
Answer:
A group of stars occupying a small portion of the celestial sphere is called a constellation.

Question b.
What points should be considered before a skywatch?
Answer:

The place for sky watching should be away from the city and as far as possible it should be new moon night.
Binoculars or telescopes should be used for skywatch.
Identifying the pole star in the north makes the skywatch easier. Hence the pole star should be used as a reference point for skywatch.
As the stars in the west set early, sky watching should begin with stars in the west.
(a) On a sky map, the north and south are towards the bottom and top of the map respectively, (b) This is because the sky map is to be held overhead in such a way that the direction we face is at the bottom side.

Question c.
It is wrong to say that the planets, stars and nakshatras affect human life. Why?
Answer:

Science has proved that the constituents of the solar system e.g. planets, satellites and comets as also distant stars and constellations do not have any influence on human life.
Man has stepped on the moon and will conquer Mars in the 21st century.
Hence, in this age of science, holding on to beliefs which have been proved wrong by numerous scientific tests, is an unnecessary waste of time and energy.
It is important to consider all these issues with a scientific frame of mind.

5. Write a paragraph on the birth and life cycle of stars using following figure.

Question a.
Write a paragraph on the birth and life cycle of stars using following figure.
Answer:
Stars are born out of nebulae. Nebulae are clouds made up mainly of hydrogen gas and dust particles which are attracted towards one another by the force of gravity, (i) As a result of pressure, the internal temperature increases and the cloud becomes dense and spherical in shape, (ii) From the diagram, life cycle of two stars can be explained.

(a) Ordinary star: (i) The ordinary star forms a Red giant star at the later stage of its evolution when it runs out of hydrogen gas at its core. (ii) At the end stage of its life it forms a white dwarf. Stars like the sun become white dwarf when its nuclear fuel is totally exhausted. (iii) It is 1% in diameter of its original size.

(b) Massive Star: (i) Massive star forms Red super giant star at the end of its life cycle, (ii) They are also called super red giants with a relatively cool outer surface, (iii) Supernova is the explosive death of the star of the end of its life with the brightness of 100 million stars in a short amount of time, (iv) A neutron star is the dense core of the supernova. (v) It is the smallest and the densest star known to exist with a 10 km radius, (vi) Neutron stars sometimes end as a black hole, (vii) Black holes are not seen from telescopes and are identified by their intense gravitational pull where even light cannot escape.

Project:

Question a.
Visit a planetarium, collect information and present it in your school on Science day.

Class 7 Science Chapter 20 In the World of Stars Important Questions and Answers

Fill in the blanks:

Question 1.
The different group of stars is known as ………….. .
Answer:
constellation

Question 2.
The pole star is ………….. .
Answer:
North star

Question 3.
The moon moves around the earth in about ………….. days.
Answer:
27 days

Question 4.
The celestial objects are ………….. .
Answer:
The stars

Question 5.
The star that lies close to the aris of rotation of the earth ………….. .
Answer:
Pole star

Question 6.
The definite elliptical path in which a planet revolves around the sun is called ………….. .
Answer:
Orbit

Question 7.
Our earth as well as the sun belongs to the galaxy which has a spiral shape called ………….. .
Answer:
milky way

Question 8.
………….. is made up of five bright stars which are distributed along the figure of the letter M.
Answer:
Sharmishtha

Question 9.
The pole star has ……………. on one-side and ……………… on the other.
Answer:
Saptarashi, Sharmishtha

Question 10.
The continuous empty space between the planets and stars in the sky is called ………….. .
Answer:
space

Name the following:

Question 1.
The brightest star in the nakshatra.
Answer:
Yogatara

Question 2.
The stars forming a group that has a recognizable shape.
Answer:
Constellation

Question 3.
Millions of stars and planets present in the sky forming a group.
Answer:
Milky way

Question 4.
The clouds from which stars are bom.
Answer:
Nebulae

Question 5.
Saptarshi constellation in English.
Answer:
Great Bear

Question 6.
The festival celebrated when sun enters Makar raashi.
Answer:
Makara Sankranti

Question 7.
The brightest star in the Orion constellation.
Answer:
Sirius

State whether the following statements are True or False. Correct the false statements:

Question 1.
The hydrogen gas and dust particles in a nebulae are attracted towards each other by gravity.
Answer:
True

Question 2.
While standing on the ground, the celestial sphere exactly below our feet is called the Zenith.
Answer:
False. The point on the celestial sphere exactly above our head is called the Zenith

Question 3.
The circle describing the apparent motion of the earth around the sun is called the ecliptic.
Answer:
False. Ecliptic is the apparent motion of sun around the earth

Question 4.
Vrushchik or Scorpio is a constellation with 10 to 12 stars.
Answer:
True

Question 5.
Makar raashi is also known as Capricorn zodiac sign.
Answer:
True

Match the following:

Question a.

Column ‘A’	Column ‘B’
1. Saptarshi	a. Divided into 88 constellations
2. Mmg nakshatra.	b. In the north direction.
3. Orion	c. Group of 7 bright stars (kite)
4. Vrushchik	d. Made up of 5 bright stars (M)
5. Pole star	e. 7 – 8 stars.
6. Celestial sphere	f. Group of 10 -12 stars

Answer:

Column ‘A’	Column ‘B’
1. Saptarshi	c. Group of 7 bright stars (kite)
2. Mmg nakshatra.	d. Made up of 5 bright stars (M)
3. Orion	e. 7 – 8 stars.
4. Vrushchik	a. Divided into 88 constellations
5. Pole star	b. In the north direction.
6. Celestial sphere	f. Group of 10 -12 stars

Answer in one line:

Question 1.
In which direction stars move in the sky except polar star?
Answer:
When seen from earth, stars appear to move from east to west.

Question 2.
What activity does IUCAA carry out?
Answer:
IUCAA which is present in PUNE carries out fundamental research in astronomy.

Question 3.
Define constellation.
Answer: A group of stars occupying a small portion of the celestial sphere is called constellation.

Question 4.
What is Nakshatra?
Answer:
The moon completes one revolution around the earth in approximately 27 days. The portion celestial sphere traversed by the moon in one day is called a nakshatra.

Question 5.
What is yogatara?
Answer:
A nakshatra is known from the brightest star that it contains. The brightest star is called the yogatara.

Define the following:

Question 1.
Horizon
Answer:
Far away the sky seems to be touching the ground. The line at which they meet is caled horizon.

Question 2.
Zenith
Answer:
While standing on the ground the point on the celestial sphere exactly above our head is called the Zenith.

Question 3.
Nadir
Answer:
While standing on the ground the point on the celestial sphere exactly below our feet is called the nadir.

Question 4.
Meridian
Answer:
The great circle which passes through both the celestial poles and the observer’s zenith and nadir is called a meridian.

Question 5.
Celestial equator
Answer:
If we uniformly expand earth’s equator in all directions indefinitely, it will penetrate the celestial sphere along a circle. This circle is known as the celestial equator.

Question 6.
Ecliptic
Answer:
The earth moves around the sun, but seen from the earth, the sun appears to move along a circle on the celestial sphere. This circle describing the apparent motion of the sun around the ‘ earth is called the ecliptic.

Question 7.
Zodiac sign
Answer:
The ecliptic has been imagined to divided into 12 equal parts. Each part subtends 30 degrees at the centre of the celestial sphere. Each of these part is called a raashi or zodiac sign.

Question 8.
Mrug Nakshatra or Orion
Answer:
It has 7 – 8 starts of which four are at the comers of quadrangle. The line passing through the three middle stars of the constellation when extended meets a very bright star. This is Vyadh or Sirius.

Find out.

Answer the following questions

Question 1.
Using a Marathi calendar collect information about 27 nakshatras, and divide them into the following 3 categories.
(i) Monsoon Nakshatra (ii) Winter Nakshatra (iii) Summer Nakshatra
Answer:
27 nakshtras: Ashwini, Bharani, Krittika, Rohini, Mrigashirasha, Ardra, Punarvasu, Pushya, Ashlesha, Magha, PurvaPhalguni, Uttara Phalguni, Hasta, Chitra, Swati, Vishakha, Anuradha, Jyeshtha, Mula, Purva Ashadha, Uttara Ashadha, Abhijit, Shravana, Dhanishtha, Shatabhishta, Purva Bhadrapada, Uttara Bhadrapada, Revati

Monsoon Season	Winter Season	Summer Season
Ashwini Karthe	Krittika	Visakha
Bharani Karthe	Rohini	Anuradha
Arudra Karthe	Mrigashirsha	Jyeshtha
Pushyani	Ardra	Mula

Aslesha	Punarvasu	Purva Ashadha
Magha		Uttara Ashadha
Purva Phalguni		Shravana
Uttara Phalguni
Chitra
Hasta

Question 2.
Write the difference between constellations Saptarshi and Mrug nakshatra
Answer:

Saptarshi	Mrug nakshatra
1. It is made up of five bright stars which are distributed along the figure of the letter M.	1. It is made up of seven-eight stars of which four are at the corners of a quadrangle.
2. Pole star is the brightest star in the constellation.	2. Sirius is the brigh jv_eutr_0n Star^ie constellation.
3. It is on the meridian in the month of April and in the month of October.	3. It is on the meridian in the month of February and in June.
4. In English, it is called the Great Bear.	4. In English, it is called Orion.

Question 3.
Draw sketches to show the relative position of prominent stars in Ursa major and Orion.
Answer:
a. Ursa major (Saptarshi) appears like a big dipper, (or kite shape). There are 3 bright stars in the handle and 4 stars in the bowl of the dipper. (It can be seen during April in summer in northern skies).

(b) Orion appears like a hunter. Three bright stars appear in the belt, 5 bright stars are arranged in the form of a quadrilateral. (It is visible during winter in the northern skies)

Question 4.
Why is the pole star important for sky watch?
Answer:

Identifying the Pole Star in the north makes the sky watch easier. Hence the pole star should be used as a reference point for skywatch.
If we extend one side of the quadrangle of Saptarshi, it reaches the Pole Star.
The pole star has Saptarshi on one side and Sharmishtha on the other.

Question 5.
What is the relation between the pole star and the constellations Saptarshi and Sharmishtha?
Answer:

Saptarshi is in the shape of a quandrangle with a tail made up 3 stars resembling a kite. If we extend one side of the quadrangle it reaches the Pole Star.
The constellations of Saptarshi and Sharmishtha are useful in locating the Pole Star.
The perpendicular bisector of the line joining the third and fourth stars in Sharmishtha goes towards the Pole star.
The Pole Star has Saptarshi on one side and Sharmishtha on the other.

Use your brain power!

Answer the following questions.

Question 1.
One Zodiac Sign = ………….. nakshatras
Answer:
27 nakshatras. Each nakshatra is divided in padas or charan. Every nakshatra has 4 padas. These 27 nakshatra complete the entire circle of 360° of zodiac.
The zodiac comprises of 360°.

Question 2.
Is sun the only star present in our Milky Way galaxy?
Answer:
No. Sun is not the only star present in the Milky Way. There are lakhs of stars in the Milky Way, some of them being many times bigger than our sun. Some of them have their own planetary systems with a great diversity in colour, brightness, as well as size.

7th Std Science Questions And Answers: