Punjab State Board PSEB 8th Class Science Book Solutions Chapter 7 Conservation of Plants and Animals Textbook Exercise Questions and Answers.
PSEB Solutions for Class 8 Science Chapter 7 Conservation of Plants and Animals
PSEB 8th Class Science Guide Conservation of Plants and Animals Textbook Questions and Answers
Fill in the blanks.
(a) A place where animals are protected in their natural habitat is called …………………..
(b) Species found only in a particular area is known as …………….. .
(c) Migratory birds fly to faraway places because of …………………. changes.
(b) endemic species
Differentiate between the following:
(a) Wildlife sanctuary and biosphere reserve
(b) Zoo and wildlife sanctuary
(c) Endangered and extinct species
(d) Flora and fauna.
(a) Difference between Wildlife Sanctuary and Biosphere Reserve.
Wildlife sanctuary is the place where wild animals are protected and preserved. Biosphere reserve is the area meant for conservation of variety of plants, animals and micro-organisms (biodiversity) found in an area.
(b) Difference between Zoo and Wildlife Sanctuary.
Zoo is a place where animals are protected in their natural habitat.
Wildlife Sanctuary is a place where wild animals are protected and preserved.
(c) Endangered and Extinct Species.
Endangered Species are the animals whose numbers are diminishing and face extinction.
Extinct Species are the species which have been disappeared from the earth.
(d) Difference between Flora and Fauna.
Flora is a collection of plants found in a particular area.
Fauna is a collection of animals found in a particular area.
Discuss the effects of deforestation on the following.
(a) Wild animals
(c) Villages (Rural areas)
(d) Cities (Urban areas)
(f) The next generation.
(a) Effect of deforestation on wild animals.
Plant and trees are the habitat and food for wild animals. So cutting of trees destroy the natural habitat of wild animals and thus they would become endangered species.
(b) Effect of deforestation on environment.
Deforestation decreases the level of oxygen in the atmosphere. Rainfall and the fertility of soil also decreases due to deforestation. As a result, there are increased chances of natural calamities like floods and drought.
(c) Effect of deforestation on villages (rural areas).
Most of the agriculture is done in rural areas. When trees and plants (deforestation) are cut down, it leads to change in soil properties.
(d) Effect of deforestation on cities (urban areas).
In cities there run more factories and automobiles. So deforestation will pollute the environment and hence the life in cities will not be healthy for living.
(e) Effect of deforestation on earth.
Deforestation leads to the increase of natural calamities like flood and drought. Deforestation leads to increase in temperature of earth causing global warming. Less trees would result in more soil erosion.
(f) Effect of deforestation on the next generation.
Deforestation leads to the climatic changes which have a great effect on the next generations. The environment becomes polluted. So the next generation would not be as prosperous as previous one.
What will happen if:
(a) we go on cutting trees
(b) the habitat of an animal is disturbed
(c) the top layer of soil is exposed ?
(a) If we go on cutting trees continuously, rainfall and the fertility of the soil will decrease. Hence there are increased chances of natural calamities such as floods and drought.
(b) If the habitat of an animal is disturbed, some of the species do not get appropriate food and shelter and with the passage of time they will come under the category of endangered species.
(c) If the top layer of the soil is exposed, the soil has less humus and become less fertile. Gradually the land converts into deserts. It is called desertification.
Answer in brief:
(a) Why should we conserve biodiversity ?
(b) Protected forests are also not completely safe for wild animals. Why ?
(c) Some tribals depend on the jungle. How ?
(d) What are the causes and consequences of deforestation ?
(e) What is Red Data Book ?
(f) What do you understand by the term migration ?
(a) Biodiversity is the variety of plants, animals and micro-organisms generally found in an area. Animals that feed on plants too are selective in their feeding habits e.g. the red panda prefers tender bamboo shoots and the koala bear of Australia feeds mostly on eucalyptus leaves. Birds and antelopes too, are very selective in their feeding habits. Wide variety of plants in the forests fulfil the needs of different herbivorous animals and strengthen the food chain. Therefore, to conserve wild life, it is necessary to conserve the rich variety of plants and animals.
(b) Protected forests are also not completely safe for wild animals because people living in the neighbourhood encroach upon them and destroy them.
(c) Some tribes depend on the jungle. Rock shelters are also found inside the Satpura National Park which are the pre-historic evidences of human life in these jungles.
Figures of animals, men shown as fighting, hunting, dancing, and playing musical instruments are depicted in these rock paintings. Figures of a man-eater tiger and a group of people are also shown in these rock paintings. Many tribals still live in the jungle.
(d) Causes of Deforestation.
Due to changing lifestyle of the people and development of technology in the 20th century, the utilization of forest products has increased tremendously. The main factors leading to the felling of trees for our comfort and convenience are:
- Requirement of more timber for housing purpose due to increase in population.
- Clearing the forest land for cultivation.
- Construction of roads and dams.
- Overgrazing by the cattle.
- Increased mining industry.
Consequences of Deforestation.
The following are the major consequences of deforestation:
- The balance of oxygen/carbon dioxide ratio in air will be disturbed.
- Excessive floods.
- Soil erosion.
- Climatic changes.
- Destruction or migration of animals and birds living in forests.
- No replenishment of ground water.
- Destruction of medicinal plants.
- Industries related to timber, rubber etc. will not flourish.
- Reduction in fertility of soil.
(e) Red Data Book.
Red Data Book is the source book which keeps a record of all endangered animals and plants. There are different Red Data Books for plants, animals and other different species.
Going far away from their original habitat of some species during a particular period of the year is called migration. Migration mostly takes place in birds. Birds migrate to other places due to climatic changes e.g. Bar headed goose, Great Cormorant, Surkhab are the migratory birds.
In order to meet the ever-increasing demand in factories and for shelter, trees are being continually cut. Is it justified to cut trees for such projects ? Discuss and prepare a brief report.
It is not justified to cut trees for such projects. Do yourself by discussing in your class.
How can you contribute to the maintenance of green wealth of your locality ? Make a list of actions to be taken by you.
We should maintain the green wealth of our locality.
- We should grow more and more trees on the either side of road.
- We should discourage the cutting of trees.
- The government should make laws to prevent the excessive cutting of trees.
- Parks should be made in a particular area.
Explain how deforestation leads to reduced rainfall.
We know that forest helps in bringing the rainfall. So deforestation leads to reduced rainfall and the fertility of soil also decreases. As a result, there are increased chances of natural calamities such as floods and drought.
Find out about the national parks in your state. Identify and show their locations in the outline map of India.
Why should paper be saved ? Prepare a list of ways by which you can save paper.
Need of saving paper.
One tonne of paper needs 17 full grown trees. So we should save paper. Paper can be recycled for 5-7 times and can be used. We should save, reuse used paper and recycle it. By this we not only save trees but also.save energy and water needed for manufacturing paper. Moreover, the harmful chemicals used in paper making will also be reduced.
List of ways of Saving Paper:
- Write on both sides of a paper.
- Re use the paper.
- Leave less margin.
- Make toys, caps etc. out of used papers.
Complete the word puzzle.
1. Species on the verge of extinction.
2. A book carrying information about endangered species.
5. Consequence of deforestation.
1. Species which have vanished.
3. Species found only in a particular habitat.
4. Variety of plants, animals and micro-organisms found in an area.
PSEB Solutions for Class 8 Science Conservation of Plants and Animals Important Questions and Answers
Multiple Choice Questions
Students saw a huge squirrel in the forest which is often found in this particular region. Rajinder asked guide about it. Guide told him that it is found in this particular area only. What is this species called ?
(a) Ordinary species
(b) Endemic species
(c) Endangered species
(d) Special species.
(b) Endemic species.
In which book, the record of endangered species is kept ?
(a) Blue Data Book
(b) Red Data Book
(c) Yellow Data Book
(d) Green Data Book
(b) Red Data Book.
What causes the migration of birds and animals ?
(a) For entertainment
(b) For Respiration
(c) For Abondonment
(d) For Reproduction.
(d) For Reproduction.
When was Project Tiger Act launched by our government ?
(a) 5 April 1973
(b) 1 April 1973
(c) 12 April 1973
(d) 14 April 1973
(b) 1 April 1973.
The increase in level of which gas causes global warming ?
Which of the following is a migratory bird ?
In which state is Kanha National Park situated ?
(b) Madhya Pradesh
(6) Madhya Pradesh
Pachmarhi Biosphere Reserve has which of the following animals ?
(a) Wild Dog
(d) All of the above
(d) All of the above.
The plants and animal found in a particular area are called:
(a) Endemic species
(c) Flora and fauna
(d) None of these
(a) Endemic species.
By how many full-grown trees one tone paper is made ?
Very Short Answer Type Questions
Fill in the blanks:
1. The removal of the top soil layer is known as ………………..
2. Wild plants and animals in the forest constitute ………………
3. Plants need ……………. gas for photosynthesis.
4. The conversion of fertile land into deserts is called …………….
5. …………………. is that part of the earth in which living organisms exist or which supports life.
6. ………………….. refers to the variety in life existing on earth.
7. Pachmarhi Biosphere Reserve consists of one national park named …………………. and two wildlife sanctuaries named ………………. and ……………. .
Satpura, Bori, Pachmarhi
8. The plants and animals found in a particular area are termed ………………. and ………………. .
9. …………………. species are exclusively found in a particular area only.
10. …………………… is a group of populations which are capable of interbreeding with each other.
Deforestation. Clearing of forests and using that land for other purposes is called deforestation.
Give some natural causes of deforestation.
Causes of Deforestation. Forest fires and severe drought are some of the natural causes of deforestation.
What is the result of decrease in rainfall and fertility of soil ?
This results in the increase of natural calamities such as floods and drought.
Which gas is needed by plant for photosynthesis ?
The plant needs carbon dioxide for photosynthesis.
What is the result of increased amount of carbon dioxide in the atmosphere ?
It leads to global warming.
What causes draught ?
Causes of Draught. Increase in temperature on earth causes draught.
Desertification. The conversion of fertile land into desert is called desertification.
Name the place which has plants and animals similar to those of the upper Himalayan peaks and those belonging to lower Western Ghats.
Pachmarhi Biosphere Reserve.
What do the government do to protect and conserve wildlife ?
The government lays down rules, methods and policies to protect and conserve them.
What is biosphere ?
Biosphere. It is that part of earth in which living beings exist or which supports life.
Biodiversity. It refers to variety in life existing on earth, their inter relationships and their relationship with the environment.
What are biosphere reserves ?
Biosphere Reserve. Biosphere reserves are the areas that are meant for conservation of biodiversity.
Name one national park and two wildlife sanctuaries in Pachmarhi Biosphere Reserve.
National Park – Satpura
Wildlife Sanctuaries – Bori and Pachmarhi.
Flora. The plants found in a particular area is called flora.
Name some flora of Pachmarhi Biosphere Reserve.
Sal, Teak, Mango, Jamun, Silver ferns, Arjun etc.
Fauna. These are the animals found in a particular area.
Name fauna of Pachmarhi Biosphere Reserve.
Chinkara, blue-bull, barking deer, leopard, wild dog, wolf etc.
Species. It is a group of population which are capable of interbreeding with each other.
What are endemic species ?
Endemic Species. These are exclusively found in a particular area only which may be any geographical unit like a state, zone or a country.
Give two endemic flora of Pachmarhi Biosphere Reserve.
- Wild mango.
Give two endemic fauna of Pachmarhi Biosphere Reserve.
- Indian giant squirrel
- Flying squirrel.
Which factors affect the natural habitat of endemic species and endanger their existence ?
- The destruction of their habitat,
- Increasing population,
- Introduction of new species.
What are Wildlife Sanctuaries ?
Wildlife Sanctuaries are some areas where wild animals are protected and preserved.
Name some important threatened wild animals.
Black duck, white eyed buck, elephant, golden cat, pink headed duck, gharial, march crocodile, python, rhinoceros, etc.
What are Zoos ?
Zoos. Zoos are also the places where animals are protected.
What are national parks ?
National parks are large and diverse reserves to protect whole sets of ecosystems.
Short Answer Type Questions
Write causes of soil erosion.
Causes of Soil Erosion:
- Top soil is carried away by wind sweeping across ploughed soil left unused in dry season.
- Dust stroms cause soil erosion.
- Loss of the forests by felling or fire starts soil erosion. Soil is carried away by rivers and streams and deposited in the oceans.
- Unprotected fields are eroded by wind and water.
- Urbanisation has led to removal of vegetation.
- Burrowing animals also contribute in soil erosion. They make the soil loose and liable to be carried away by water.
- Human activities, such as felling of trees, overgrazing, overcropping and faulty tilling, accelerate soil erosion.
How can soil be conserved ?
- Stopping clear-cutting of forests and overgrazing of ranges, check soil erosion by streams and rivers.
- Intensive cropping helps in checking soil erosion. A field always under a crop is protected against soil erosion.
- Bunds around the fields contain rain water and check soil erosion besides washing away of minerals.
- Irrigation channels in the fields should be so designed as to carry water at a slow speed.
- Drainage canals to carry flood water will protect the fields against soil erosion.
- Contour ploughing (ploughing along a slope rather than up and down) checks soil erosion by water.
- Erosion of soil by wind may be stopped by planting trees and growing grass. Tree belts round fields act as wind breakers.
Write importance of wild life.
Importance of Wild Life:
- Plants, animals and microorganisms provide many things to us.
- Ecological balance is maintained by maintaining food chains and natural cycles.
- Maintenance of gene bank for breeding programmes.
- Wild animals are source of fun and recreation to public. .
- It is a source of inspiration to poets and artists.
- It is source of aesthetic value.
Write two differences between endangered and vulnerable species.
Differences between endangered and vulnerable species
|Endangered species||Vulnerable species|
|1. They have extreme danger of dying out and disappearing.||1. They face some danger of dying out.|
|2. They may become extinct.||2. They have danger of entering category of endangered species.|
Explain biosphere reserves.
It is a specified area in which multiple use of land is permitted by dividing it into certain zones and each zone is specified for particular activity.
The concept of Biosphere Reserve has been evolved by Man and Biosphere (MBA) programme of UNESCO. In the biosphere reserve, multiple land use is allowed by designating various zones such as core, buffer zone and manipulation zone. In a biosphere reserve, wild population, traditional life ,style of tribals and varied domesticated plant and animal genetic resources are protected.
Discuss the concept of “endangered species.”
The species (or taxa) which are on the verge of extinction and whose survival is unlikely if the causal factor continue to be operating. These are species with only limited number of individual survivals. They are in immediate danger of extinction e.g., the great Indian bustard bird which is inhabitant of the semiarid areas of Rajasthan, Gujarat and Maharashtra is highly endangered bird.
What are the factors responsible for global warming ?
The continuously rising levels of carbon dioxide and some other gases in the air result in an increase in the temperature of atmosphere causing warming up of the atmosphere of earth i.e. global warming.
Why are the forests considered to be an important natural resource ?
The forests are considered to be a significant natural resource on the earth because:
- they help in maintaining the balance of oxygen and CO2 gases in the air and thus sustain life.
- they help in bringing rain.
- they regulate climate.
- they help in replenishing ground water,
- they control floods.
- they prevent soil erosion.
- they provide a living place to a large number of plants and animals.
- they provide us many medicinal plants.
- they provide many plant products such as rubber, gums, resins, honey, lac, katha etc.
- they decrease run off rate of rain water.
- they provide conditions for wild life, the main source of meat for tribal societies.
What measures should be taken for the replenishment of forests ?
Measures for Replenishment of Forests.
Man is utilizing the natural resources to fulfil his needs in modern times. However, if the forests are removed for our comforts, it will ultimately lead to elimination of the human species from the surface of the earth. The following measures should be adopted for replenishment of forests:
- Growing more plants.
- Judicious use of plant products.
- Prevent overgrazing by the cattle.
- Strict law enforcement for setting up mining and other industries in. . around forests.
- Mobilising the public opinion through electronic and print media.
- Establishing forest nurseries.
How do plants check soil erosion ?
The underground parts of the plants (i.e. roots) help in binding the soil particles. The soil with plant cover is not eroded by water or wind. Hence, plants check the soil erosion.
Why is it necessary to have a wide variety of plants in a forest ?
It is essential to have a wide variety of plants in a forest due to the following reasons:
- selective feeding habits of animals.
- fulfil the needs of animals as well as human beings.
- provide shelter to a number of organisms.
- a stable diversified food chain/food web offers a better chance of survival to the animals living in the forest.
Name five National Parks.
- Corbett National Park in Uttrakhand.
- Kanha National Park in Madhya Pradesh.
- Sanjay National Park in Maharashtra.
- Periyar National Park in Kerala.
- Bannughatta National Park in Karnataka.
Explain how large scale deforestation could lead to depletion in ground water resource.
Vegetation helps the soil to retain water which ultimately replenishes the ground water resource. In recent times, large forest areas have been cleared for various purposes. Overgrazing too has destroyed vegetation and the barren land so formed, has lost the capacity to hold water. And thus there is a depletion in ground water resource.
To protect a forest means to conserve air, soil and water. Explain.
The forest is complex biological system. Though it is self-sufficient, it depends on the other renewable resources to maintain itself. Therefore, to protect a forest it is necessary to conserve air, soil and water. A forest relies on specific climatis conditions for its survival. At times, large scale man-made geographical alterations such as huge dams and excessive mining have disturbed the environment of the region causing severe damage to the forests in the area. Air pollution from industries situated even miles away have similar ill-effects on the forests.
How does habitat destruction affect wildlife ?
Animals and plants have a strong relationship with their habitat. Certain living organisms can survive only in a specific kind of environment. The golden lion tamarins were found in a small area of Brazilian rain forests. It was their only natural habitat. When this area was destroyed, the beautiful little golden coloured mammal became homeless.
Although, Brazil has many more rain forests, today, few golden lion tamarins survive only in the zoos and probably will never be able to return to the wild habitat because their natural habitat has been destroyed by man. When a forest dies, a large number of animals become endangered or extinct.
Name at least seven wild animals of Khangchendzena National Park, which face the danger of extinction.
Wild animals of Khangchendzena National Park which face extinction are snow leopard, clouded leopard, marbled cat, Himalayan black bear, civet binturong, red panda Tibetian wild ass, blud sheep, serow, goral, takin, musk deer and green pigeon.
What is an ecosystem ?
Ecosystem. The biotic community together with the physical environment (abiotic components) forms an interacting system called the ecosystem. It may be natural or artificial. An ecosystem may be temporary e.g. crop field or permanent e.g. forest. An ecosystem may be as big as an ocean or forest or as small as wood. Thus ecosystem is any structural and functional unit of the environment that can be identified.
Ecosystem is an interacting system consisting of a community (living) components and environment (abiotic components) where both influence each other.
What are the advantages of silviculture ?
Silviculture is the major project started to replenish forest. It is of two-fold advantages:
- Produces large quantities of raw materials.
- Increases the area under forests.
What are the functions of biosphere reserves ?
Functions of Biosphere Reserve:
- It helps to maintain the biodiversity of that area.
- It helps to maintain the culture of that area.
- It may also contain some other protected area.
Name some animals which are preserved in our wild life Sanctuaries. What do these sanctuaries pose ?
Some of the important threatened wild animals like black buck, white eyed buck, elephant, golden cat, pink headed duck, gharial, marsh crocodile, python, rhinoceros, etc. are protected and preserved in our wild life sanctuaries. Indian sanctuaries pose unique landscapes, broad level forests, mountain forests and virgin bush lands in deltas of big rivers.
Write a note on migratory birds.
Migratory Birds. Birds who cover long distances to reach another land are known as the migratory birds. The migratory birds are Bar Headed Goose, Great Cormorant. Migratory birds fly to far away specific areas every year during a particular time because of climatic changes. They fly for laying eggs as the weather in their natural habitat becomes very cold and inhospitable.
Write a note on reforestation.
It is the restocking of the destroyed forest by planting more new trees. We should plant at least as many trees as we cut. Reforestation can take place naturally also. If the deforested area is left undisturbed, it re-establishes itself. If we have to retain our green wealth for generations, plantation of more trees is required.
Government of India has implemented the National Forest Policy in 1952. It aimed at forest coverage of one-third of the total land area of the country. On the failure of this policy, Indian government revised the policy in 1980. This was named Forest (conservation) Act. This act aimed at preservation and conservation of natural forests and meeting the basic needs of the people.
Long Answer Type Questions
List the steps for conservation of wild life.
Steps for conservation of wild life :
- To preserve the endangered species.
- Proper planning and management of land and water so as to protect the natural habitat.
- Maximum varieties of food crops, farage plants, timber trees, livestock, animals for aquaculture and their wild relatives should be preserved to maintain gene bank.
- Each country should identify the habitat of wild relatives of economically useful organisms and should preserve them.
- Wild areas should be protected to preserve the habitat of migratory or wild ranging animals.
- To check the over-exploitation of the useful organisms.
- International trade in wild plants and animals should be regulated.
- Protection of wild life from the activities of poachers and hunters. Indian government enacted “Wild Life Protection Act” in 1972 to declare hunting as an unlawful act.
- Emphasis should be laid on the development and creation of parks and sanctuaries, where threatened species could be preserved or introduced.
- The observance of “wild life week” is made an annual feature with a view to educate the masses of the importance of wild life.
- It is proposed to establish breeding farms, especially for threatened species, so that they can be reared in semi-natural conditions and then introduced in parks and sanctuaries.
List a few advantages of forests.
Advantages of Forests:
- Forests conserve fertility of soil.
- Forests cause rains and maintain water cycle.
- Forests provide Wood. Indian forests yield valuable timbers, wood like teak, sal, deodar, shisham etc.
- Forests provide Paper. The conifers and bamboos are used as raw material to prepare paper.
- Medicinal plants of forests provide medicines of great importance.
- Forests provide number of products like resins, gums, rubber, food and insecticides.
- Forests also provide the cork e.g. oak (Quercus).
- The other useful products which are obtained from the forest e.g. shellac, natural dyes, lac, honey, wax, etc.
- Rayon and artificial silk are obtained from cotton linters.
- Plastics are also prepared from cellulose nitrate.
- Natural rubber is also obtained from the forests.
- Forests provide fuel wood.
- Forests provide essential oils which are obtained from rosha grass, khas and sandal wood. They are used in the manufacture of soaps, cosmetic, pharmaceuticals, confectionary, pipe and tobacco.
- Soap substitute such as ritha and shikakai are important commercial products.
- Forests have a great aesthetic value.
Give some sketches of flora and fauna of Pachmarhi Biosphere Reserve.