Lakhmir Singh & Manjit Kaur: Conservation of Plants And Animals- 3 | Lakhmir Singh & Manjit Kaur Solutions: Class 8 Science PDF Download

Q.61. (a) What is meant by the term ‘Wildlife’? Why should forests and wildlife be conserved?
(b) What are the various measures which can be taken to conserve forests and wildlife?

(a) (i) Wildlife traditionally refers to undomesticated animal species, but includes all plants, fungi, and other organisms that grow or live wild in an area without being introduced by humans.

(ii) We should protect forest and wildlife because Forests provide us oxygen, they cause rainfall, prevents soil erosion, Plants depend on animals and birds for their pollination and seed dispersal. Forests provide us various medicines. Various forest products are used as raw materials in industries.
(iii) The wild life including animal, plant and marine biodiversity keeps ecosystems functional and balanced. Healthy ecosystems allow us to survive, get enough food to eat and make a living. Biodiversity is critical to ending poverty and promoting shared prosperity for the millions who depend on nature for their livelihoods.

(b) (i) To survey and collect all the information about wildlife, especially, their number and growth.

(ii) To delimit the areas of their natural habitat.

(iii) To protect wildlife from pollution and from natural hazards.

(iv) To impose complete restriction on hunting and capturing of wildlife.

(v) To protect habitat by protecting forests.

Q.62. (a) What are the various purposes for which the forest trees are cut?
(b) What is effect of deforestation on wild animals?

(a) (i) Trees are cut down for many reasons.

(ii) Trees are cut to make space to build new houses and to clear land to grow crops for human consumption, grass for animals like domestic and milch animals so they can produce dairy foods. The trees are also cut down for production of paper and making of furniture. Sometimes trees are cut to make roads and buildings.

(b) The effect of deforestation on wild animals is severe. The animals lose their natural habitat. They have to look for alternate habitat. Further due to loss of trees, the availability of food is scarce. The food chain is disturbed. In the absence of trees, if there is heavy rainfall, animals drown in flood. Due to deforestation the rains become scanty and animals die due thirst as natural water bodies dries up.

Q.63. (a) How does deforestation cause soil erosion?
(b) Explain how, deforestation leads to frequent flooding of rivers.

(a) Deforestation means cutting of trees. When trees are cut, the soil becomes loose. When there is heavy rainfall or flood, the soil being loose is washed away and this leads to soil erosion. This leads to flood and landsliding.

(b) Deforestation plays several roles in the flooding equation Tree roots hold the soil in place, reducing the movement of sediment that can shrink river channels downstream. However in the absence of trees, soil is loosened, and it gets washed away easily with water or torrential rains and is deposited into river. When rivers have soil and water level more than their holding capacity, it lead to over flooding and causes floods.

Q.64. (a) Explain how, deforestation leads to reduced rainfall.
(b) How does deforestation lead to global warming?

(a) Plants need carbon dioxide for the process of photosynthesis. Fewer trees would mean that less carbon dioxide will be used up resulting in its increased amount in the atmosphere and increase in greenhouse effect. The increase in temperature on the earth disturbs the water cycle and may reduce rainfall. When number of trees are reduced then less amount of water is evaporated and hence the reduced evaporation leads to reduced rainfall.

(b) Deforestation leads to global warming. When trees are there, during the process of photosynthesis, the carbon dioxide (CO₂) is used and oxygen is give out. When there are more and more no trees they use more carbon dioxide and give out oxygen and bring more rainfall. However when the number of trees are few, the amount of carbon dioxide is increased. Carbon dioxide causes greenhouse effect and global warming. The reduce rainfall also increases the temperature and causes global warming.

Q.65. What is a Biosphere Reserve? Name any two Biosphere Reserve of India. Where are this Biosphere Reserve located?

Biosphere Reserves (BRs) are representative parts of natural and cultural landscapes extending over large area of terrestrial or coastal/marine ecosystems or a combination thereof and representative examples of bio-geographic zones/provinces. They are protected and minimally disturbed area of nature conservation. The two biospheres reserves in India are Pachmarhi biosphere reserve in Madhya Pradesh and Nanda Devi in Uttrakhand.

Q.66. The part of earth in which living organism exist (or which supports life) is called:
(a) Lithosphere
(b) Globe
(c) Hydrosphere
(d) Biosphere

Correct Answer is option (d)

The biosphere is the global ecological system integrating all living beings and their relationships, including their interaction with the elements of the lithosphere, geosphere, hydrosphere, and atmosphere. It is due to coexistence of these spheres the life can exist on earth.

Q.67. Deforestation increases the level of one of the following in the atmosphere. This one is:
(a) Ozone
(b) Carbon dioxide
(c) Oxygen
(d) Water vapour

Correct Answer is option (b)

Deforestation leads to increase in level of carbon dioxide. This leads to increase in greenhouse effect and global warming.

Q.68. Which of the following is not a part of Pachmarhi Biosphere Reserve?
(a) Bori Wildlife Sanctuary
(b) Satpura National Park
(c) Bandipur National Park
(d) Pachmarhi Wildlife Sanctuary

Correct Answer is option (c)

Bandipur National Park, an 874-sq-km forested reserve in the southern Indian state of Karnataka, is known for its small population of tigers.

Q.69. The most rapidly dwindling natural resources in the world is:
(a) Water
(b) Soil
(c) Sunlight
(d) Forests

Correct Answer is option (d)

Forests are full of natural resources and due to human activities like deforestation, agricultural cleaning of land and urbanisation is depleting at a quick rate.

Q.70. Which of the following animal is no longer found in Satpura National Park in Madhya Pradesh?
(a) Wild buffalo
(b) Wild boar
(c) Marsh crocodile
(d) Wild dog

Correct Answer is option (a)

Wild buffalo has become extinct about 50 years back from Satpura park.

Q.71. Those species (of plants and animals) which are found only in a particular area are called:
(a) Epidemic species
(b) Pelagic species
(c) Pandemic species
(d) Endemic species

Correct Answer is option (a)

Endemic plants are special because they are found in only one location on the planet, and nowhere else. It is due to the their survival in particular climatic and geological conditions.

Q.72. The migratory bird which comes from Siberia to India for a few months every year is:
(a) Crow
(b) Koel
(c) Crane
(d) King fisher

Correct Answer is option (c)

Crane comes to India because of favourable weather for breeding In SIberia the weather conditions are very harsh.

Q.73. Sanjay Gandhi Wildlife Sanctuary is in:
(a) Rajsthan
(b) Manipur
(c) Madhya Pradesh
(d) Maharashtra

Correct Answer is option (d)

Sanjay Gandhi National Park, formerly Borivali National Park, is a large protected area in the northern part of Mumbai city in Maharashtra State in India.

Q.74. Which of the following activities, if not checked in time, may ultimately lead to the rise in sea level causing the flooding of low-lying coastal areas?
(a) Desalination
(b) Desertification
(c) Deforestation
(d) Desegregation

Correct Answer is option (c)
Deforestation leads to increase in the floods as rain water is washed away into rivers. As level of water in rivers and eventually increases it leads to flooding of low-lying areas. In addition, the increased greenhouse effect due to deforestation leads to high temperature and melting of snow. This agains increases the water level in rivers and flooding of low-lying areas coastal areas.

Q.75. Snakes are killed in large numbers because:
(a) They are very poisonous
(b) They kill rates
(c) Their skin is expensive
(d) They damage the crops

Correct Answer is option (c)
The snake expensive skin is sold in market for expensive drugs and ointment.

Q.76. The National Park which is in Rajasthan is:
(a) Corbett National Park
(b) Kanha National Park
(c) Satpura National Park
(d) Sariska National Park

Correct Answer is option (d)
Sariska Tiger Reserve is a national park and tiger reserve in the Alwar district of the state of Rajasthan India and it has reserves of wildlife like leopard, crocodiles, Sambar, Chitel, Nilgai, Chausingha, Wild Boar and Langur.

Q.77. Which of the following wild animals is not listed in the Red Data Book of India?
(a) Black buck
(b) Flying squirrel
(c) Tiger
(d) Leopard

Correct Answer is option (d)
Indian leopard (Panthera pardus fusca) is a leopard subspecies widely distributed on the Indian subcontinent. About 12,000 to 14,000 leopards were speculated to live in the entire country and are not added in the Red Data Book of India

Q.78. The Siberian crane comes to India every year in winter for a few months:
(a)  To escape the severe summer
(b)  To escape the severe winter
(c)  To escape the heavy rains
(d)  To escape from predators

Correct Answer is option (d)
The siberian crane comes to India and is found in Satpura as the weather in Siberia is extreme with scarcity of food and light.

Q.79. Which of the following wild animals is a friend of the farmer?
(a)  Deer
(b)  Rat
(c)  Snake
(d)  Wild buffalo

Correct Answer is option (c)
Snake is a friend of farmer because it eats the rodents that cause damage to crops.

Q.80. Which of the following is an extinct species of animals?
(a) Tiger
(b) Desert cat
(c) Snow leopard
(d) Dodo

Correct Answer is option (d)
The Dodo is an extinct flightless bird endemic to the island of Mauritius, east of Madagascar in the Indian Ocean.

Q.81. Which of the following is not a consequence of deforestation?
(a) Increase in soil erosion
(b) Increase in earth’s temperature
(c) Decrease in rainfall
(d) Decrease in floods

Correct Answer is option (c)
Deforestation leads to increase in floods. It leads to a decrease in rainfall and water level.

Q.82. One of the following is not a part of the fauna of Pachmarhi Biosphere Reserve. This one is:
(a) Yak
(b) Leopard
(c) Blue bull
(d) Barking deer

Correct Answer is option (a)

The domestic yak (Bos grunniens) is a long-haired domesticated bovid found throughout the Himalaya region of southern Central Asia, The yak-rearing states of India are Arunachal Pradesh, Sikkim, Uttar Pradesh, Himachal Pradesh and Jammu and Kashmir.

Q.83. The indiscriminate killing of which of the following animals can lead to loss in the production of flood grains?
(a) Birds
(b) Snakes
(c) Grasshoppers
(d) Rats

Correct Answer is option (b)

Snakes killing can increase the number of rodents. When a number of rodents increase they eat away and destroy the crops and hence cause loss in the production of grains.

Q.84. Which of the following activities can help in the conservation of forests?
(a) Recycling of cotton shirts
(b) Recycling of silks blankets
(c) Recycling of jute ropes
(d) Recycling of cardboard cartons

Correct Answer is option (d)

Cycling of cardboard cartons will lead to a decrease in the level of tree cutting and hence conserve forests.

Q.85. Which of the following is an endangered species of animals?
(a) Dinosaur
(b) Asiatic lion
(c) Irish deer
(d) Hyena

Correct Answer is option (b)

The Asiatic lion, also known as the Indian lion and Persian lion, is a lion subspecies that lives as a single population in India’s Gujarat State. It is listed as Endangered on the IUCN Red List because of its small population size.

Q.86. Large scale deforestation leads to the decrease in the amount of gas A in the atmosphere whereas the amount of gas B increases. The increased amount of gas B in the atmosphere causes an effect C which leads to excessive heating of the earth and its atmosphere producing an undesirable phenomenon D. What are A, B, C and D?

A: Oxygen; B: Carbon dioxide; C: Greenhouse effect; D: Global warming.

Q.87. A highly poisonous animal Z which inhabits crop field is commonly known as friend of the farmer. It eats up pests like Y and saves the crops from damage. The animal X is killed in large numbers to get its Z which sells in the market at a high price. What are X, Y and Z?

X:: Snake; Y: Rats; Z:: Skin

Q.88. The species P and Q of wild animals are found only in a ‘particular area’. The species R of wild animals is listed in Red data book of India whereas species S of wild animals no longer exists anywhere on the earth.
(a) What name is given to species like P and Q?
(b) What are the species like R known as?
(c) Name one species like R.
(d) What is the special name of species like S?
(e) Name one species like S.

(a) Endemic species

(b) Endangered species

(c) Tiger

(d) Extinct species

(e) Dinosaur

Q.89. Consider the following animal species:

Dodo, Yak, Deer, Black buck, Tiger, Cow, Kashmir stag, Dinosaur, Elephant, Lion tailed macaque, Peacock, Snow leopard

Which of these animals are:

(a) endemic to mountain habitats?

(b) endangered species?

(c) extinct species?

(a) Yak; Kashmir stag; Snow leopard

(b) Blackbuck; Tiger; Kashmir stag; Lion tailed macaque; Snow leopard

(c) Dodo; Dinosaur

Q.90. X is a human activity which will cause an increase in temperature of earth’s atmosphere leading to global warming. It can cause soil erosion making the soil infertile and lead to desertification. It can cause decrease in rainfall but increase the flooding of rivers. It can also affect water cycle and lead to the extinction of many wild species. What is X?

X is Deforestation that affect water cycle and lead to the extinction of many wild species.