Samacheer Kalvi 8th Science Solutions Term 3 Chapter 8 Conservation of Plants and Animals

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Tamilnadu Samacheer Kalvi 8th Science Solutions Term 3 Chapter 8 Conservation of Plants and Animals

Samacheer Kalvi 8th Science Conservation of Plants and Animals Text Book Exercise

I. Choose the best answer:

Question 1.
The plants found in a particular area are known as …………….
(a) fauna
(b) flora
(c) endemic
(d) rare
Answer:
(c) endemic

Question 2.
Deforestation means …………….
(a) cleaning of forest
(b) to grow plants
(c) to look after plants
(d) None of these
Answer:
(d) None of these

Question 3.
The Red Data Book gives a list of …………….
(a) endemic species
(b) extinct species
(c) natural species
(d) None of these
Answer:
(d) None of these

Question 4.
Insitu conservation is …………….
(a) off site conservation
(b) on site conservation
(c) Both a and b
(d) None of these
Answer:
(b) on site conservation

Question 5.
Wildlife Protection Act was implemented in …………….
(a) 1986
(b) 1972
(c) 1973
(d) 1971
Answer:
(b) 1972

II. Fill in the blanks:

1. WWF stands for …………….
2. The animal found in a particular area is known as …………….
3. Red Data Book is maintained by …………….
4. Mudhumalai Wildlife Sanctuary is located in ……………. district.
5. ……………. is observed as ‘World Wildlife day’.

Answer:

1. World Wildlife Fund
2. endemic
3. International Union for conservation of Nature
4. Nilgiris
5. March 3

III. Match the following:

1. Gir national park – Madhya Pradesh
2. Sundarabans National Park – Uttarangal
3. Indira Gandhi National Park – West Bengal
4. Corbett National Park – Gujarat
5. Kanha National Park – Tamil Nadu

Answer:

1. Gir national park – Gujarat
2. Sundarabans National Park – West Bengal
3. Indira Gandhi National Park – Tamil Nadu
4. Corbett National Park – Uttarangal
5. Kanha National Park – Madhya Pradesh

IV. Answer very briefly:

Question 1.
What is global warming?
Answer:
Gases methane and carbon dioxide accumulating in the atmosphere and trap the heat energy inside the atmosphere leading to increase in temperature is called Global warming.

Question 2.
What is known as extent species?
Answer:
Species which no longer exist on Earth are called extinct species.

Question 3.
Give few example for extinct species.
Answer:
Dinosaurs and Dodo are examples of extinct species.

Question 4.
Name two endangered animals.
Answer:

1. Snow Leo pard
2. Asiatic Lion

Question 5.
What is ICBN?
Answer:
International Code of Botanical Nomenclature. These are a set of International rules proposed by botanists to ensure a stable, universal and uniform system of naming plants.

V. Answer briefly:

Question 1.
What is biosphere reserve?
Answer:

1. Biosphere is a protected area where human population also forms the part of the system.
2. The area of these places will be around 5000 square kilometers. They conserve the eco system, species and genetic resources. These areas are set up mainly for economic development.

Question 2.
What is tissue culture?
Answer:
It is a technique of growing plant cells, tissues, organs, seeds or other plant parts in a sterile environment on a nutrient medium.

Question 3.
What is endangered species? Give two examples.
Answer:

1. An endangered species is an animal or a plant that is considered to be at the risk of extinction.
2. It means that there are only few of them left on the Earth and soon they might extinct.
3. Snow leopard, Bengal tiger, Asiatic lion, Purple frog and Indian giant squirrel are some of the endangered animals in India.

Question 4.
Write the advantages of the Red Data Book.
Answer:

1. It helps to evaluate the population of a particular species.
2. The data given in this book can be used to evaluate the species at the global level.
3. The risk of a species becoming globally extinct can be estimated with the help of this book.
4. It provides guidelines for implementing protective measures for endangered species.

Question 5.
Mention four main reasons for the conservation of forests.
Answer:

1. According to WWF (World Wildlife Fund) there has been 60% decrease in the size of population of animals, birds, fish, reptiles and amphibians over the past 40 years.
2. In order to leave something for the future generation, we need to conserve it now.
3. Conservation is the protection, preservation, management of wildlife and natural resource such as forest and water.
4. Conservation of biodiversity helps us to protect, maintain and recover endangered animals and plant species.

Question 6.
What do you understand by the term bio-magnification?
Answer:

1. Bio – magnification is the increase in contaminated substances due to the intoxicating environment.
2. The contaminants might be heavy metals such as mercury, arsenic, and pesticides such as polychlorinated biphenyls and DDT (Dichloro Diphenyl Trichloro ethane).
3. These substances are taken up by the organisms through the food they consume.
4. When the organisms in the higher food chain feed on the organisms in the lower food chain containing these toxins, these toxins get accumulated in the higher organisms.

Question 7.
What is PBR?
Answer:
1. Peoples Biodiversity Register is a document which contains comprehensive information on locally available bio-resources including landscape and demography of a particular area or village.

2. Bio-resources mean plants, animals and microorganisms or parts thereof, their genetic material and by-products with actual or potential use or value.

3. A Biodiversity Management Committee is set up in each local body which prepares the People’s Biodiversity Registers with the guidance and technical support of National Biodiversity Authority and the State Biodiversity Boards.

4. Preparation of this register promotes conservation, preservation of habitats and breed of animals and gathering of knowledge relating to biological diversity.

5. The register entails a complete documentation of biodiversity in the area related to the plant, food source, wildlife, medicinal source, traditional knowledge etc.

VI. Answer in detail:

Question 1.
What is Deforestation? Explain the causes and effects of Deforestation.
Answer:
Destruction of forests in order to make the land available for different uses is known as deforestation.
Causes of Deforestation:

• Fires and floods are the natural causes for deforestation.
• Human activities are responsible for deforestation include agricultural expansion, cattle breeding, illegal logging, mining, oil extraction, dam construction and infrastructure development.

1. Agricultural Expansion:

• With increasing population, there is an overgrowing demand for food production.
• Hence, large amount of trees are chopped down for crops and for cattle grazing.

2. Urbanization:

• Increase in population needs the expansion of cities.
• More land is needed to establish housing and settlement.
• Requirements like construction of roads, development of houses, mineral exploitation and expansion of industries also arise due to urbanisation.
• Forests are destroyed to meet all these needs.

3. Mining:

• Mining of coal, diamond and gold require a large amount of forest land.
• Large number of trees are cut down to clear the forest area. The waste that comes out from mining pollutes the environment and affects the nearby plants.

4. Construction of dams:
To provide water supply to the increasing population, large size dams are constructed. Hence, a great extend of forest area is being cleared.

5. Timber Production:

• Wood-based industries like paper, match-sticks, furniture need a substantial amount of wood supply.
• Wood is the most commonly used fuel, thus, a large number of trees are being cut down for fuel supplies.
• Illegal wood cutting is the main reason for the destruction of some valuable plants.

6. Forest fire:

• Forest fire be caused by humans, accidents or natural factors.
• Forest fires wipe out thousands of acres of forest land each year all over the world. This has tremendous effects on biodiversity and the economy as well.

7. Cyclones:
Cyclones destroy the trees on a massive scale.

Effects of Deforestation:
1. Extinction of species:
Deforestation has resulted in the loss of many wonderful species of plants and animals and many are on the verge of extinction.

2. Soil Erosion:

• When the trees are cut down, soils are exposed to the Sun’s heat.
• Extreme temperature of the summer dries up the moisture and makes the nutrients to evaporate, ft also affects the bacteria that helps in the breakdown of organic matter.

3. Water cycle:
When trees are cut down, the amount of water vapour released decreases for transpiration and hence there is a decrease in the rainfall. ‘

4. Floods:
When the trees are cut down, the flow of water is disrupted and it leads to flooding.

Question 2.
Discuss the advantages of Insitu and exsitu conservation.
Answer:
Advantages of In-situ conservation:

1. Species can be adapted to their habitat.
2. Species can interact with each other.
3. Natural habitat is maintained.
4. It is less expensive and easy to manage.
5. Interests of indigenous people are protected.

Advantages of Exquisite conservation:

1. It prevents the decline of species.
2. Endangered animals can be breeded in these ways.
3. Threatened species are breeded and released in natural environment.
4. It is useful for conducting research and scientific work.

Question 3.
Write about the types of conservation.
Answer:
Conservation is the protection, preservation, management of wildlife and natural resource such as forest and water.

Types:
In-situ conservation:
It is conservation of living resources within the natural ecosystem in which they occur.

1. National Parks:

• It is an area which is strictly reserved for the betterment of the wildlife.
• Here, activities like forestry, grazing or cultivation are not permitted.
• Eg – Guindy National Park in Chennai district.

2. Wildlife sanctuaries:

• A sanctuary is a protected area reserved for the conservation of animals only.
• Human activities like harvesting of timber, collection of forest products and private ownership rights are allowed here.
• Controlled interference like tourist activity is also allowed.

3. Biosphere reserves:

• It is a protected area where human population also forms the part of the system.
• The area of these places will be around 5000 square kilometers.
• They conserve the eco system, species and genetic resources.
• Eg – These areas are set up mainly for economic development.

Ex-situ Conservation:
It is the conservation of wildlife outside their habitat. Establishing zoos and botanical gardens, conservation of genes, seedling and tissue.

1. Botanical gardens:

• It is a place where flowers, fruits and vegetables are grown.
• These places provide a healthy and calm environment.

2. Zoological parks:

• Zoological parks are the areas where wild animals are conserved.
• In India there are about 800 zoological parks.

3. Tissue Culture:
It is a technique of growing plant cells, tissues, organs, seeds or other plant parts in a sterile environment on a nutrient medium.

4. Seed bank:
The seed bank preserves dried seeds by storing them in a very low temperature.

5. Cryo Bank:
It is a technique by which a seed or embryo is preserved at a very low temperature.

Question 4.
Write a note on Blue Cross.
Answer:
1. Blue Cross is a registered animal welfare charity in the United Kingdom, founded in 1897 as Our Dumb Friends League.

2. The vision of this charity is that every pet will enjoy a healthy life in a happy home.

3. The charity provides support for pet owners who cannot afford private veterinary treatment, helps to find homes for unwanted animals, and educates the public in the responsibilities of animal ownership.

4. Captain V. Sundaram founded the Blue Cross of India, the largest animal welfare organization of Asia in Chennai in the year 1959.

5. He was an Indian pilot and animal welfare activist. Now, Blue Cross of India the country’s largest animal welfare organizations and it runs several animal welfare events like pet adaptation and animal right awareness.

6. Blue Cross of India has received several international and national awards.

7. This organization is entirely looked after by volunteers.

8. The main office is located at Guindy, Chennai, with all amenities like hospitals, shelters, ambulance services and animal birth controls, etc.

9. Activities of the organization include, providing shelters, re-homing, adoption, animal birth control, maintaining hospitals and mobile dispensary and providing ambulance services.

VII. HOT:

Question 1.
Is it possible to find Dinosaurs today? Why?
Answer:

1. No. It is not possible to find Dinosaurs today since they have become extinct.
2. The reasons may be shortage of food, space or climate changes.

Question 2.
Animals are affected by Deforestation. How?
Answer:

1. Deforestation involves destruction of forests by man to make the lend available for different uses.
2. When forests are destroyed, the wild animals living there are left homeless.
3. They start moving out in search of shelter.
4. Since animals start moving out the food chains are also affected and animals cannot find food also.
5. They also get isolated from their groups and may be killed by accidents or hunted.

Question 3.
Why did the numbers of Tiger and Black buck decrease?
Answer:

1. The number of Black buck and Tigers have decreased due to excessive hunting, Deforestation and habitat degradation.
2. Tigers are also facing problems of prey depletion since the number of deers and other herbivores are decreasing due to disappearance of forests.

Samacheer Kalvi 8th Science Conservation of Plants and Animals Additional Question

I. Choose the correct answer:

Question 1.
…………… is not a green house gas.
(a) Oxygen
(b) Carbon dioxide
(c) Nitro-us oxide
(d) Methane
Answer:
(a) Oxygen

Question 2.
Chipko Movement was started in ……………
(a) 1980
(b) 1970
(c) 1960
(d) 1953
Answer:
(b) 1970

Question 3.
Each year …………… is celebrated as ‘World Biodiversity Day’.
(a) April 20
(b) May 22
(c) December 8
(d) October 12
Answer:
(b) May 22

Question 4.
…………… is not an endangered animal.
(a) Nilgiri Tahr
(b) Asiatic Lion
(c) Snow leopard
(d) Dodo duck
Answer:
(d) Dodo duck

Question 5.
Yeoman Butterfly has been declared as state butterfly of ……………
(a) Manipur
(b) Nagaland
(c) Tamil Nadu
(d) West Bengal
Answer:
(c) Tamil Nadu

II. Fill in the blanks:

1. The founder of Chipko movement was ……………
2. In a Cryo bank, the seeds are preserved in ……………
3. The variety of life forms is called …………….
4. Replanting of trees is called ……………
5. The details of endangered species can be viewed in ……………
6. Blue cross of India was established in …………… in India.
7. …………… has led to destruction of coral seeds.
8. …………… Biosphere reserve is located in Tamil Nadu.
9. National park is an example for …………… conservation.
10. World Wild life Day is celebrated on …………….

Answer:

1. Sunderlal Bahuguna
2. liquid nitrogen
3. Biodiversity
4. Reforestation
5. Red Data Book
6. Chennai
7. Biomagnification
8. Nilgiri
9. In-situ
10. March 3rd

III. Very short answer:

Question 1.
What is Reforestation?
Answer:
Reforestation is the natural or intentional replanting of the existing forests that have been destroyed through deforestation.

Question 2.
Differentiate Afforestation and Reforestation.
Answer:
Afforestation:

1. Trees are planted in new areas where there was no forest cover.
2. One sapling is planted to get one tree.
3. It is practiced to bring more area under forest

Reafforestation:

1. It is practiced in areas where forests have been destroyed.
2. Two saplings are planted to replace every felled tree
3. It is practiced to avoid deforestation.

Question 3.
Name two endangered plant species?
Answer:
Malabar Lily and Rafflesia flower.

Question 4.
What are the functions of CPCSEA?
Answer:

1. Approval of animal house facilities.
2. Permission for conducting experiments involving usage of animals.
3. CPCSEA stands for ‘The Committee for the Purpose of Control and Supervision of Experiments on Animals.
4. It is a statutory committee set up under the Preservation of Cruelty to Animals Act,1960.

Question 5.
The Red Data Book is maintained by which organisation?
Answer:

1. Red Data Book is maintained by the International Union for Conservation of Nature.
2. It is an international organization working in the field of nature conservation and sustainable use of natural resources.

IV. Long Answer:

Question 1.
List some measure to save endangered species.
Answer:

1. Animal species are endangered mainly because of hunting and poaching. If it is controlled, there can be a significant change in the number of endangered animals.
2. Controlling pollution can have a positive impact on animals, fish and birds all over the world.
3. By consuming less pollutants, we can protect the ecosystems.
4. Animals often mistake plastic for food and hence plastics harm and cause endangerment of many species. Limiting the amount of plastic and recycling it can save the endangered animals.
5. Recycling things and buying Eco friendly products will preserve the environment resources and hence the animals.
6. Pesticides and chemicals which cause damage to the environment should be avoided.
7. Planting native trees will provide food to the animals.

Question 2.
What are causes for endangerment of species?
Answer:

1. Loss of habitat.
2. Trees that provide food and shelter to so many species are destroyed due to human intervention.

Over hunting and poaching:
Large number of animals is hunted for their horns, skin, teeth and many other valuable products.

3. Pollution:

• Number of animals are affected by pollutions like air pollution and water pollution.
• In the recent years more number of animals is affected by wastes in the form of plastic.

4. New habitat:

• Sometimes animals are taken by people to new habitat where they do not naturally live.
• Some, of them may extinct and some may survive.
• The new ones may also get attacked by the species already living there and cause their extinction.

5. Chemicals:

• We use pesticides and other chemicals to get rid of damaging insects, pests or weeds.
• But they can also poison desired plants and animals if we do not use them correctly.

6. Diseases:
Diseases due to various unknown reasons may affect the animals and make them extinct.

7. Natural calamities:
Animals may also be destroyed due to natural disasters like flood and fire.

Question 3.
Explain the significance of Afforestation.
Answer:

1. Afforestation helps the wild animals and even humans to have shelter and to find their food source.
2. Through afforestation we can increase the supply of oxygen. Trees planted can increase the water vapour in the atmosphere to get the rainfall.
3. By planting trees the amount of carbon dioxide in the atmosphere can be reduced and thus the effects of air pollution, green house gases and global warming can be controlled.
4. Afforestation enables us to avoid desertification of land.
5. Barren lands experience strong winds and it causes soil erosion. Top soil is washed away during rainfall. Afforestation helps to grow more trees so that they can hold the top soil along with the nutrients.
6. Creating forests provides us fodder, fruits, firewood and many other resources.
7. Industries need specific type of trees. Afforestation helps us to grow a particular type of trees.