WBBSE 10th Class Science Solutions Science & Environment Chapter 5 Environment, its Resources and their Conservation

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West Bengal Board 10th Class Science Solutions Science & Environment Chapter 5 Environment, its Resources and their Conservation

WBBSE 10th Class Life Science & Environment Solutions

TOPIC – 1

NITROGEN CYCLE

SUMMARY

Our environment is composed of both living and non-living things. Nitrogen is an important element for organisms. 78.09% of the air is nitrogen. Nitrogen, like other elements also moves through biotic and abiotic components of ecosystem, which is known as nitrogen cycle or N₂ cycle.
The main stages of nitrogen cycle are-biological and non-biological fixation of nitrogen from atmosphere, entry of nitrogen into organism from soil, re-entry of nitrogen into the soil through ammonification, nitrification and denitrification or release of N₂ into air.
Conversion of atmospheric nitrogen into nitrogenous compound is called nitrogen fixation. The atmospheric nitrogen is fixed by several prokaryotes, i.e. some soil bacteria (Azotobacter and Clostridium), some cynobacteria (Nostoc, Anabaena) and some symbiotic bacteria (Rhizobium). Also atmospheric nitrogen is converted into nitrous oxide by electrical energy of lightning, which is brought down by rain and is used by plants.
Ammonifying bacteria like Bacillus mycoides convert excretory substances of organisms and dead organic matter into ammonia. Nitrifying bacteria like Nitrosomonas convert ammonia into nitrate and nitrite called nitrification. Finally nitrate and nitrite is converted into N₂ and released into atmosphere by denitrifying bacteria like Pseudomonas, Thiobacillus.
Human activities, such as, use of fertilisers greatly increase the amount of nitrogen that is cycling between the living world and soil, water and atmosphere. This results in increased global concentrations of N₂O, which causes global warming, substantial acidification of water bodies and soil.

Long Answer Type Questions

1. Describe nitrogen cycle with the help of a flowchart.*

Similar question, Show the steps of nitrogen cycle with the help of a flow chart.

Part question, Analyse the role of bacteria at any three steps of nitrogen cycle.

Ans. Nitrogen cycle

Nitrogen cycle is a bio-geochemical process which involves different phases, which are-nitrogen fixation in soil, entry of nitrogen from soil into living organisms, return of nitrogen from organisms to soil and liberation of nitrogen in atmosphere. The phases are explained the next section.

Nitrogen fixation: By this process, atmospheric nitrogen is trapped in soil. This occurs by three different processes, which are-
1. Natural N₂ fixation: During lightning, huge amount of heat is generated in the atmosphere, when nitrogen and oxygen react gradually to produce nitric oxide (NO) and nitrogen dioxide (NO₂). When rainwater mixes with atmospheric nitrogen dioxide two acids, namely nitrous acid (HNO₂) and nitric acid (HNO₃) are produced. The reactions are given below-
  
  These two acids then react with the minerals present in soil and form nitrates (potassium nitrate, calcium nitrate, etc.).
2. Biological fixation: Biological nitrogen fixation is done in the following ways-[i] Soildwelling nitrifying bacteria like Azotobacter sp., Clostridium sp., etc. absorb atmospheric nitrogen and trap it in their cells. When these bacteria die, the nitrogenous compounds mix in soil. [ii] Cyanobacteria like Anabaena sp., Nostoc sp. absorb nitrogen from atmosphere and add it to the soil. [iii] Rhizobium sp. present in root nodules of leguminous plants traps atmospheric nitrogen and converts it into nitrogenous compounds. With the death of the host plants, these compounds mix in soil to increase its nitrogen content:
3. Industrial fixation: In fertiliser industries, different nitrogen-rich fertilisers are produced. By Haber-Bosch method, N₂ and H_₂ are made to react at 300-400°C under 35-100 MPa (Mega Pascal) pressure to produce NH₃. This NH₃ and other nitrogen-rich fertilisers when added to soil increases the nitrogen content.
Entry of nitrogen from soil into living organisms: Plants absorb soluble nitrogenous salts from soil through their roots. This nitrogen takes part in synthesising plant proteins. Animals get the nitrogen either directly or indirectly by consuming plants. Finally, plant proteins are transformed into animal proteins and remain in the animal bodies.
Return of nitrogen from organisms to soil: Nitrogen returns from the body of organisms to soil through two different steps. These are-
1. Ammonification: The ammonifying bacteria (Bacillus mycoides, Micrococcus sp., etc.) act upon dead animal and plant bodies and the excretory materials to convert the nitrogenous compounds in it into ammonia. This is called ammonification.
2. Nitrification: Certain nitrifying bacteria convert ammonia into nitrates through two steps of reactions. [1] Nitritation-In the first step, Nitrosomonas sp. converts ammonia and ammonium ions into nitrites. [1] Nitratation-In the next step, soil-dwelling Nitrobacter sp. transforms nitrites into nitrates.
Liberation of nitrogen into the atmosphere or denitrification: In this phase, several bacteria act upon nitrites and nitrates in soil and liberate free nitrogen into the atmosphere. This biochemical process is called denitrification. Pseudomonas sp., Thiobacillus sp., etc. are few bacterial species, which help in denitrification.

2. ‘Nitrogen cycle is affected due to human activities’-State two phenomena to justify it.

Explain the adverse effects of excess nitrogen in the atmosphere, liberated due to human activity.

Similar question, Explain any three incidences which are occuring as a result of disruption of nitrogen cycle.

Ans. Human actions affecting nitrogen cycle

The human actions affecting nitrogen cycle are discussed below.

Application of nitrogen-rich fertilisers: Nowadays, farmers apply excess amount of nitrogen-rich fertilisers in crop fields to increase productivity. Due to this practice, content of N₂O and NO₂ is rising alarmingly in the atmosphere.
Cultivation of nitrogen-fixing plants: Leguminous plants like gram, peas, lentil, soyabean, etc. are important sources of plant protein. To fulfil the need of protein, different pulses are being cultivated more and more. These plants efficiently absorb nitrogen from atmosphere and trap it in soil.
Burning of fossil fuel: Excessive burning of fossil fuel such as mineral oils, coal, etc. increases nitric oxide (NO), nitrous oxide (N_₂O) and nitrogen dioxide (NO_₂) in air. It increases supply of nitrogen in the environment.

Adverse effects of excess nitrogen in atmosphere due to human activity

The adverse effects of excess nitrogen in the atmosphere, due to human activity, are mentioned below.

Global warming: Nitrous oxide (N₂O) is a potent greenhouse gas. Accumulation of this gas in air arrests more heat in the atmosphere and causes global warming,
Acid rain: Oxides of nitrogen present in atmosphere mix with rainwater to produce nitrous and nitric acids. These acids come down on earth as acid rain, which acidify soil and water bodies to cause serious environmental pollution.
Photochemical smog: Nitric oxide (NO), released as automobile exhaust, reacts with atmospheric hydrocarbons in presence of sunlight. This reaction produces a polluting gas, named PAN (Peroxy-acetyl nitrate). It mixes with smoke and creates a very harmful photochemical smog, This reduces visibility through air, causes inflammation of respiratory tract and various other respiratory diseases.

3. Explain the microbial fixation of atmospheric nitrogen in nitrogen cycle.

Ans. Microbial fixation of atmospheric nitrogen in nitrogen cycle

Certain microorganisms are capable of absorbing atmospheric nitrogen and trapping it in soil This mechanism of trapping of atmospheric nitrogen with the help of microorganisms is called biological nitrogen fixation. Two types of microorganisms take part in this process, which are described here.

Nitrogen fixation by free-living microbes: Few freeliving soil-dwelling bacteria like Clostridium sp., Azotobacter sp. and few cyanobacteria like Anabaena sp. (a symbiont with Azolla as well), Nostoc sp., etc. absorb atmospheric nitrogen and convert it into nitrogenous compounds within their cell. As the microbes dies these nitrogenous compounds mix in soil to increase its nitrogen content.
Nitrogen fixation by symbiotic microbes: Rhizobium sp. is a soil-dwelling bacterium, which enters into root tissues of leguminous plants and stays there as symbiont. As the bacterium enters into the host tissue, the root cells start to divide quickly to form nodules. Rhizobium, inhabiting in these root nodules, absorbs atmospheric nitrogen and converts it into various nitrogenous compounds. A portion of these nitrogenous compounds is supplied to the host plant and the rest is stored in the microbial cell body. When these plants die and are decomposed, these nitrogenous compounds get mixed in soil, to increase the fertility of the soil.

Short Answer Type Questions

1. What is meant by bio-geochemical cycle

Ans. The continuous cycling of different elements (C, H, N, O, P, S, Ca, etc.) among biotic and abiotic components of the environment is called biogeochemical cycle. Nitrogen cycle is an important bio-geochemical cycle in the environment.

2. What will happen if bio-geochemical cycle is disrupted?

Ans. If bio-geochemical cycle is disrupted, the balance of the important elements in the environment would have been disturbed. This may lead to natural disasters.

3. Why deficiency of basic elements does not occur in the environment?

Ans. Deficiency of basic elements never occur in the environment, because living organisms never uptake any element permanently from the environment. The organisms release such elements as compounds through excretion. Alternatively, these are liberated in the environment by decomposition of the dead and decaying organic matters.

4. What is nitrogen cycle?

Ans. Nitrogen cycle, is a bio-geochemical cycle, which describes how nitrogen circulates among the atmosphere, the soil and living organisms. So, by the help of this bio-geochemical cycle, the content of nitrogen in atmosphere and in living organisms remains unaltered.

5. Mention the importance of nitrogen in living of wagen in living organisms.

Ans. The main structural component of a living body is protein. Nitrogen, on the other hand, is the main structural element of protein. That is why, nitrogen is important for all living organisms.

6. What is meant by nitrogen fixation?

Ans. Atmospheric nitrogen is trapped into the soil in the form of different nitrogenous compounds by a number of physico-chemical or biochemical processes. These processes are collectively known as nitrogen fixation.

7. What is meant by biological nitrogen fixation?

Ans. Certain blue-green algae or cyanobacteria and a few bacteria absorb nitrogen directly from atmosphere and reduce it to ammonia with the help of an enzyme, nitrogenase. This ammonia then assimilates in the protoplasm of these microbial organisms. This biochemical trapping of atmospheric nitrogen is called biological nitrogen fixation.

8. What is formed by the reaction between atmospheric nitrogen and oxygen during lightning?

Ans. During lightning, large amount of heat is generated in sky, when nitrogen and oxygen react gradually to produce nitric oxide (NO) and nitrogen dioxide (NO₂). The reactions are given below.

N₂+ O₂ → 2NO, 2NO + O₂ → 2NO₂

9. What happens when rainwater mixes with atmospheric nitrogen dioxide?

Ans. When rainwater mixes with atmospheric nitrogen dioxide two acids, namely nitrous acid (HNO₂) and nitric acid (HNO₃) are formed. The reaction is mentioned below.

2NO₂ + H₂O → HNO₂ + HNO₃

10. What is ammonification?

Ans. The biochemical process, by which dead animal and plant bodies or nitrogenous waste matters are acted upon by certain bacteria to produce ammonia, is known as ammonification. Bacillus mycoides, Micrococcus sp., etc. are few examples of ammonifying bacteria.

11. What is nitrification?

Ans. The biochemical process, by which soil ammonia is first converted into nitrite and finally into nitrate, is known as nitrification. Nitrosomonas, Nitrobacter, etc. are few examples of nitrifying bacteria that help in this process.

12. What is denitrification?

Ans. The biochemical process, by which nitrate or any other nitrogenous compounds break to liberate free nitrogen into the atmosphere, is known as denitrification. Certain bacteria like Thiobacillus, Pseudomonas, etc. are denitrifying in nature.

13. Mention the role of bacteria in nitrogen cycle.

Ans. The role of bacteria in nitrogen cycle are as follows [1] Certain bacteria trap atmospheric nitrogen and reduce it to form ammonia. [2] Few other, then convert this ammonia into nitrite. [3] Certain other bacteria, then transform nitrite into nitrate. [4] A few other bacteria break nitrates to liberate elementary nitrogen into atmosphere.

14. Mention the role of bacteria nitrification.

Ans. Bacteria like Bacillus mycoides, Micrococcus sp., etc. reduce nitrogen from decomposing organic matters to ammonia. produce Nitrosomonas sp. then converts the ammonia into nitrites. Nitrobacter sp. acts upon these nitrites and oxidises them to stable nitrates. This is how bacteria help in nitrification.

15. Mention the importance of soil-living microbes.

Ans. Soil-living microbes help in decomposition of dead organisms and other organic matters. By this process, several simple organic compounds and elements mix in soil to prepare humus. This humus gradually increases nutrients in soil and makes it more fertile.

16. Mention the role of bacteria in increasing soil fertility.

Ans. Free-living soil bacteria like Azotobacter, Clostridium, etc. and symbiotic bacteria like Rhizobium absorb atmospheric nitrogen and trap it in the form of nitrogenous compounds. These compounds increase the nitrogen content in soil, thus, increasing soil fertility.

17. Write names of two microorganisms participating in the process of biological nitrogen fixation.

Ans. The two microorganism participating in the process of biological nitrogen fixation areAzotobacter (free-living) and Rhizobium (symbiotic).

18. What is humus?

Ans. After the death of animals and plants, the bodies are decomposed and various organic matters mix in the soil. This brownish, sticky organic matter, which is generally acidic in nature, is known as humus.

19. What is leghaemoglobin?

Ans. Leghaemoglobin is a pinkish red pigment present in the nitrogen-absorbing root nodules of leguminous plants. The structure of this pigment and capacity of absorbing oxygen is similar to that of haemoglobin. This pigment is present in the space between the symbiotic bacterial cell and the surrounding host cells.

20. Why do leaves of insectivorous plants have different modifications?

Ans. Insectivorous plants grow in such soil, where nitrogen content is significantly low. To compensate the short supply of nitrogen, these plants trap insects and digest them to absorb protein from their body. To trap insect prey efficiently, the leaves of insectivorous plants show various types of modification. Example-Pitcher plant, sundew, etc.

21. What are decomposers?

Ans. Decomposers are the microorganisms, which putrefy or decompose the dead organisms and excretory materials to liberate simple elementary components from complex organic matters. Example-Different bacteria and fungi.

22. What role do the decomposers play in the environment?

Ans. Decomposers putrefy dead organisms and excretory materials and convert complex organic matters into simple matters. This process maintains the reserve of elements in the environment, thus, maintaining the balance among different elementary nutrients. Other than this, decomposers keep the environment clean by disposing the decaying matters.

23. Relate the following phenomena with the trend of disturbance in nitrogen cycle resulting from different human activitiesGlobal warming, Acidification of soil and water of river and lake.

Ans. Global warming: Around 40% increase of N₂0 (nitrous oxide) in the environment is due to human activities. N₂O is released in the environment as a result of combustion of fossil fuel and overuse of nitrogen-rich fertilisers. This N₂O is a greenhouse gas that absorbs infrared radiation or heat of the sunlight which reflects on the earth and facilitates greenhouse effect and global warming.

Acidification of soil and water of river and lake: Oxides of nitrogen get dissolved in rainwater and form nitric acid, which is a major component of acid rain. Acid rain destroys aquatic plants and animals and disrupts the ecological equilibrium of rivers lakes, ponds, etc. Apart from this, destruction of forest resources, harm of architecture and monuments take place due to acid rain.

24. How does acidification affect environment?

Ans. Air polluting gases like nitric oxide (NO), other nitrogenous oxides, sulphur oxides, etc. mix with rainwater and come down as acid rain. This acidic rainwater mixes with soil and different water bodies to acidify them which harm the various components of the environment. This is how acidification affects environment:

25. Mention the significance of nitrogen cycle.

Ans. The significance of nitrogen cycle are as follows-[1] Nitroge cycle to maintain the nitrogen balance in the environment. [2] The amount of nitrogen necessary for the synthesis of protein is supplied to the living bodies from nitrogen cycle. By this process, nitrogen cycle helps in sustaining the race of life.

Very Short Answer Type Questions

Multiple Choice Questions & Answers [MCQ]

1. The most abundant gas in the atmosphere is-

A. Oxygen

B. Hydrogen

C. Carbon dioxide

D. Nitrogen

Ans. D

2. Which of the following is not involved with nitrogen cycle?

A. Nitrification

B. Eutrophication

C. Ammonification

D. Denitrification

Ans. B

3. The plant, which traps and consumes insects to fulfil the need for nitrogen, is –

A. Sarpagandha (Rauvolfia)

B. Nayantara (Catharanthus)

C. Sunflower

D. Pitcher plant

Ans. D

4. Plants can absorb nitrogen from soil in the form of-

A. NO₂ only

B. N₂O

C. NO

D. NO₂ and NO₃

Ans. D

5. A nitrogen-fixing bacterium is-

A. Nitrosomonas

B. Azotobacter

C. Nitrobacter

D. Mycobacterium

Ans. B

6. The microorganism inhabiting the root nodules of sweet pea plant is-

A. Nostoc

B. Anabaena

C. Chlamydomonas

D. Rhizobium

Ans. D

7. Amonification is the formation of-

A. Ammonia from nitrates by decomposers

B. Ammonia from nitrogen

C. Ammonia from amino acids

D. Ammonia from nitrates by nitrogen fixers

Ans. C

8. Which of the following is not a nitrogen-fixing bacterium?

A. Rhizobium

B. Mycobacterium

C. Nostoc

D. Azotobacter

Ans. B

9. Majority of nitrogen fixation occurs by-

A. Biological nitrogen fixing organisms

B. Natural process by lightning

C. Volcanic eruptions

D. Haber-Bosch process

Ans. A

10. Which of the following components is increased in soil due to cultivation of leguminous plants in it?

A. Oxygen

B. Carbon dioxide

C. Sulphur dioxide

D. Nitrogen

Ans. D

11. Application of nitrogen in soil-

A. Reduces fertility

B. Increases fertility

C. Has no effect on fertility

D. Increases pH

Ans. B

12. The percentage of nitrogen in atmosphere is about-

A. 0.08

B. 20.60

C. 1.40

D. 78.09

Ans. D

13. The component of air, which neither plants nor animals can absorb directly, is

A. Oxygen

B. Carbon dioxide

C. Nitrogen

D. Both A and B

Ans. C

14. The enzyme by which nitrogen-fixing bacteria anaerobically convert atmospheric nitrogen into ammonia, is

A. Nitrogenase

B. Amylase

C. Pectinase

D. Galactase

Ans. A

15. Conversion of ammonia into nitrate is called-

A. Ammonification

B. Denitrification

C. Calcification

D. Nitrification

Ans. D

16. The blue-green algae capable of absorbing nitrogen from atmosphere is-

A. Chlamydomonas

B. Clostridium

C. Anabaena

D. Rhodochorton

Ans. C

17. A nitrogen-releasing bacterium is-

A. Thiobacillus

B. Rhizobium

C. Nostoc

D. Diatom

Ans. A

18. The bacteria, which can trap atmospheric nitrogen in soil in the form of nitrogenous compounds, are called-

A. Symbiotic bacteria

B. Ammonifying bacteria

C. Nitrogen-fixing bacteria

D. Saprophytic bacteria

Ans. C

19. Bacillus mycoides is a type of-

A. Symbiotic bacterium

B. Ammonifying bacterium

C. Denitrifying bacterium

D. Nitrifying bacterium

Ans. B

20. Which of the following is correct regarding nitrogen cycle?

A. N₂ cycle is a bio-geochemical cycle

B. The major reservoir of N₂ is atmosphere

C. N₂ is the most abundant nutrient for plants

D. All of these

Ans. D

21. A soil-dwelling free-living nitrogen fixing bacterium is-

A. Clostridium

B. Nostoc

C. Anabaena

D. Diatom

Ans. A

22. Nitrate in soil is transformed into ammonia and then into free nitrogen by bacterial action. This process is called-

A. Nitrification

B. Ammonification

C. Denitrification

D. Symbiosis

Ans. C

23. Which of the following nitrogenous compounds is increased in atmosphere due to human activity?

A. N₂O

B. NO

C. NH₃

D. All of these

Ans. D

24. A nitrogenous greenhouse gas is-

A. NH₃

B. N₂O

C. HNO₃

D. All of these

Ans. B

25. The nitrogenous compounds responsible for ozone depletion are-

A. NH₄OH and HNO₃

B. NO and NO₂

C. HNO₂ and HNO₃

D. NH₃ and HNO₂

Ans. B

26. The nitrogenous compound responsible for acid rain is-

A. NO₂

B. NO

C. HNO₃

D. All of these

Ans. D

27. Which of the following phase of nitrogen cycle Pseudomonas is associated with?

A. Nitrogen fixation

B. Nitrification

C. Denitrification

D. Amnonification

Ans. C

28. Which of the following microbes take part in nitrification?

A. Nitrosomonas

B. Azotobacter

C. Pseudomonas

D. Thiobacillus

Ans. A

Answer in a single word or sentence

1. Name the process of cyclic rotation of various elements and inanimate matters in the biosphere.

Ans. Bio-geochemical cycle

2. Mention the role of bio-geochemical cycle.

Ans. Bio-geochemical cycle maintains the balance among different elements of the environment.

3. Name a gas that is essential for all plants but they cannot absorb it directly from the atmosphere?

Ans. Nitrogen

4. Name a denitrifying bacterium.

Ans. Thiobacillus denitrificans

5. Mention the types of microorganisms which help in biological fixation of nitrogen in soil.

Ans. Biological nitrogen fixation occurs in soil by free-living microorganisms and symbiotic microorganisms.

6. Name the pinkish red pigment present in the root nodules of leguminous plants.

Ans. Leghaemoglobin

7. Name a nitrogen-fixing free-living bacterium.

Ans. Clostridium

8. Name a nitrogen-fixing symbiotic bacterium.

Ans. Rhizobium leguminosarum

9. Name a nitrifying bacterium.

Ans. Nitrosomonas

10. In which form does nitrogen stay in soil?

Ans. Nitrogen stays in soil in the form of nitrate and nitrite salts.

11. Give examples of two cyanobacteria, which are capable of fixing nitrogen from atmosphere.

Ans. Anabaena and Nostoc

12. Which role is played by fungi in the environment?

Ans. Fungi play the role of decomposers in the environment.

13. Name two plants which feed on insects to obtain nitrogen.

Ans. Pitcher plant and sundew plant

14. Name the process where nitrates are converted into free nitrogen.

Ans. Denitrification

15. Name the two steps of nitrification.

Ans. Nitritation and nitratation

16. By which process of nitrification, nitrite produced from ammonia?

Ans. Nitritation

17. Which type of bacteria convert nitrates into free nitrogen?

Ans. Denitrifying bacteria

18. Name the process of ammonia formation by decomposition of dead and decaying organic matters.

Ans. Ammonification

19. Name two non-leguminous nitrogen-fixing plants.

Ans. Pine and Azolla

20. Which enzyme helps to catalyse the reactions for N₂ fixation?

Ans. Nitrogenase

Fill in the blanks

1. The process of trapping atmospheric nitrogen in soil is known as ……….

Ans. Nitrogen fixation

2. ………… develops root nodules in the root system of leguminous plants.

Ans. Rhizobium

3. Anabaena is an example of ………..

Ans. Cyanobacteria

4. During lightning, …………. is produced in atmosphere by the combination of nitrogen and oxygen.

Ans. NO

5. Nitrosomonas is a type of ………….. bacterium.

Ans. Nitrifying

6. ………… is a bacterium which helps in conversion of nitrite into nitrate.

Ans. Nitrobacter

7. Another name of ammonification is …………..

Ans. Mineralisation

8. Pea, gram and other pulses are known as ………… plants.

Ans. Leguminous

9. Rhizobium is a …………… nitrogen-fixing bacterium.

Ans. Symbiotic

10. NO₂ of atmosphere mixes with rain water to produce …………. and nitric acid.

Ans. Nitrous

11. Azotobacter is a …………… nitrogen-fixing bacterium.

Ans. Free-living

12 .At the ………… phase of nitrogen cycle ammonia is converted into nitrite and nitrate by the action of some bacteria.

Ans. Nitrification

TOPIC – 2

ENVIRONMENTAL POLLUTION

SUMMARY

The unwanted change of the biosphere of environment through the introduction of harmful, poisonous substances in the environment is called pollution and the substances causing pollution are called pollutant.
Different types of greenhouse gases, like-CO₂, CH₄, etc. are the main causes of air pollution. Except these, some suspended particulate matter (SPM) also can cause air pollution, Acid rain and various diseases of respitatory tract (COPD) are the main harmful effects of air pollution.
The major causes of water pollution are agricultural waste, microbes, etc. One of the notable harmful effects of water pollution is eutrophication which is caused by excessive plant and algal growth due to the addition of excessive level of inorganic and organic nutrients in the water bodies. Due to this phenomenon, quality of the water gets deteriorated. Cholera, typhoid are some of the diseases caused by the water pollution.
Microbes and chemical fertilisers, chemical pesticides induce soil pollution. From the polluted soil, these pollutants can directly enter into human body. Non-biodegradable pollutants get accumulated in th environment and may cau in bioaccumulation and biomagnification. Bioaccumulation is the accumulation of pollutants in an organism and biomagnification is the increase in concentration of pollutant along the successive higher trophic levels in a food chain.
Various types of sounds from industries and vehicles are the major causes which contribute to noise or sound pollution. Noise pollution causes hearing impairment, cardiac diseases, stress, sleep disturbance, etc. Sound intensity is measured by the unit decible (dB).

Long Answer Type Questions

1. ‘A lot of indiscriminate activities of humans pollute environment’-Support the statement by giving three examples in favour of it.

Mention the different types of pollution.

Ans. Three examples in favour of the statement

A lot of indiscriminate activities of human beings pollute environment in large scale. These are[1] Combustion of fossil fuels causes excessive increase in the level of greenhouse gases which in turn result global warming. [2] Excessive use of chemical fertilisers and pesticides causes soil pollution. [3] Industrial sewage, oil spill, etc. create water pollution. These examples justify the statement correctly.

Different types of pollution

Based on the nature of the environmental resources, pollution can be classified into four types. These are-[1] Air pollution, [2] Water pollution, [3] Soil pollution and [4] Noise pollution.

2. What is air pollution? Mention the causes of air pollution.

Ans. Air pollution

Air pollution is the natural or man made undesirable change in the atmosphere, with the addition of harmful, hazardous substances in such higher concentraton that these exert toxic effect on vegetation and animal life with a degradation of biotic and abiotic resources. Air pollution results in the accumulation of harmful smokes, gases, vapour, suspended particulate matters, etc. in the atmosphere beyond admissible level.

Causes of air pollution

Main causes of air pollution are-Greenhouse Gases (GHG) and Suspended Particulate Matters (SPM).

Greenhouse gases: Various gases present in atmosphere, like carbon dioxide (CO₂), methane (CH₄), ozone (O₃), chlorofluorocarbon (CFC), nitrous oxide (N₂O), etc. prevent dissipation of heat from earth surface and make the atmosphere warmer. These gases are called greenhouse gases. By different human activities or natural processes, these gases gets accumulated in the atmosphere. The sources of a few greenhouse gases are as follows-[A] Carbon dioxide: Combustion of fossil fuel, forest fire, burning of organic matters, furnace of factories, etc. add CO₂ in the atmosphere. [B] Chlorofluorocarbon: This gas is liberated from air conditioners and refrigerator factories, jet engine exhausts. It is also present in aerosol sprays and deodorants. [C] Nitrogen oxides: It is released from the nitrogenous fertilisers and chemical factories. Lightning naturally produces nitrogen oxides in atmosphere.
SPM: Different light and fine particulate matter remain suspended in air. These are called suspended particulate matters, which cause air pollution. These matters include particles below 10 μ in diameter, denoted as PM-10. Smaller particles below 2.5 μ are marked as PM-2.5. Besides these, there are very fine particles of aerosols, which are below 1μ in diameter. Important SPM are dust particles, pollen grains, ash, smoke, etc.

3. Briefly describe any five measures to reduce the effect of greenhouse gases.

Ans. Measures to reduce the effect of greenhouse gases

Five different measures to reduce greenhouse effect are discussed below.

Reducing the use of fossil fuels: By reducing the use of fossil fuels like coal, petrol, diesel, etc., production of CO₂ can be minimised.
Reducing the use of CFC-producing devices: CFC is liberated from refrigeration industries and different aerosol sprays like perfumes, deodorants, etc. Reducing the use of CFC in these products may reduce the CFC-created greenhouse effect.
Afforestation: Plants consume CO₂ from the atmosphere. By planting of more trees, the area of forests can be widened and this practice ca reduce the CO₂ content of the atmosphere.
Use of non-conventional sources of energy: Use of non-conventional sources of energy like solar energy, geothermal energy, wind energy, etc. can bring down the use of fossil fuels and thereby, reduce the chances of production of greenhouse gases.
Processing of sewage: Proper processing of sewage before disposal can reduce the possibilities of production of methane. Thus the occurrence of greenhouse effect can be lessen.

4. What is acid rain? Mention the cause of acid rain.

Ans. Acid rain

Atmospheric pollutants like sulphur dioxide and nitrogen dioxide react with water vapour present in the atmosphere to produce secondary air pollutants like sulphuric acid and nitrous or nitric acids. These acids come down to earth with rainwater, dew or snowfall and cause serious environmental and health hazards. This is called acid rain. The pH of acid rain goes down below 5.

Cause of acid rain

The principal cause of acid rain is air pollution. These pollutants are generated from different human activities. Chemical factories release huge quantity of sulphur dioxide (SO₂). Automobile exhaust releases nitrogen dioxide (NO₂). Sulphur dioxide reacts with oxygen present in nature to produce sulphur trioxide (SO₃). SO₃ and NO₂ react with atmospheric moisture and produce sulphuric acid (H₂SO₄), nitrous (HNO₂) and nitric acid (HNO₃). Following reactions take place in atmosphere when these acids are generated.

Finally, these acids come down on earth with rainwater as acid rain.

5. Briefly explain the effects of acid rain on environment.

Part question, Mention two damages as a result of acid rain.

Ans. Effects of acid rain on environment

Various harmful effects of acid rain on different components of environment can be seen.

Effect on animals and plants: Acid rain acidifies water bodies and as a result fishes die. If pH of a water body goes below 4 due to acid rain, all types aquatic animals and plants die. Acid rain damages the leaves of plants. In terrestrial habitat, several agricultural crops are severely damaged due to acid rain.
Effect on soil: Acid rain makes the soil acidic. As a result of this, fertile soil gradually loses fertility. Productivity of crops also drops radically. Many beneficial micro and macroorganisms die due to acidification of soil.
Effect on forests: Acid rain may damage wide area of forestland. The leaves get bleached and burnt. Finally, a large number of trees dry up. Similar effect can be observed on corp plants. As a result of this, crop productivity also decreases drastically.
Effect on human health: Acid rain has very moderate harmful effects on human beings. Mostly first splash of acid rain causes damage to human hair and skin. Prolonged intake of acidified water may cause serious gastro-intestinal problem.
Effect on marble architecture: Marble and limestone are composed of calcium carbonate. Acids present in acid rain reacts with this to produce calcium nitrate and calcium sulphate. Because of this chemical change, marble gets corroded and becomes rough and porous. This is popularly known as ‘stone leprosy’ or ‘stone cancer! Several marble monumnets such as Taj Mahal, Victoria Memorial have faced the adverse effect of acid rain.

6. Briefly mention different types of lung diseases caused due to air pollution.

Ans. Different types of lung diseases caused due to air pollution

Polluted air, when enters into the lungs through respiratory path, causes various diseases. These are-[1] Air pollutants like CO₂ and different oxides of nitrogen may cause several lung diseases like asthma, bronchitis, pneumonia, pharyngitis and even lung cancer. [2] Workers of metallurgical industries, chemical factories, etc. may develop different lung diseases caused by different air pollutants. [3] Over the time, cool miners get exposed to coal dust. Due to this, their lungs become black. Hence, this disease is called black lung disease. [4] Workers of asbestos and silicon factories are exposed to airborne fine asbestos fibres and silicon dust. These often develop asbestosis and silicosis respectively. [5] Due to smoking and inhaling various air pollutants, the trachea becomes narrow. As a result, numerous individuals suffer from COPD or Chronic Obstructive Pulmonary Disease.

7. Luxurious and comfortable lifestyle is one of the major reasons of air pollution’-Support the statement with arguments.

How does the amount of methane increase in the atmosphere?

Ans. Explanation to support the statement

‘Luxurious and comfortable lifestyle is one of the major reasons of air pollution’-this statement can be well supported and explained by the facts, like-[1] CFC used in refrigerators and air conditioners caused global warming, destroys ozone layer and renders harmful effects of UV rays on environment to increase. [2] Methane gas produced during natural gas extraction causes global warming. [3] Different oxides of sulphur, nitrogen and smoke from agricultural and industrial field enhances the chances of acid rain and causes different respiratory disorder.

Reason of increase of methane in the atmosphere

Methane is produced due to partial combustion of certain organic matters, putrefaction of dead plants and animals in wetlands and emission from coal mines. These processes increase the percentage of methane in atmosphere.

8. State the causes of water pollution.

Part question, Make your opinion based on your experiences how the sources of fresh water becomes polluted.

Ans. Causes of water pollution

Different causes of water pollution are-

Agricultural wastes: During heavy shower, the toxic materials like insecticides, herbicides, etc. are washed away from the agricultural fields and mix in the water bodies in order to make the water polluted. This runoff also contains nitrate-rich, phosphate-rich chemical fertilisers, etc. which increase nutrient level of water bodies and result into algal bloom. This phenomenon is called eutrophication. This increases BOD of the water body and makes it unsuitable for living for aquatic animals.
Domestic and industrial sewage: Domestic wastes contain several organic matters, detergents, excreta, etc. On the other hand, industrial sewage contains boiling water (produced by thermal power plants) and numerous toxic chemicals. Sewage also carries numerous pathogenic germs. These materials when disposed in streams, rivers and sea, cause massive water pollution.
Oil spill: Mineral oils often spill from large oil vessels. These oils make a thin film over the surface of sea and cause sea water pollution.
Heavy metals: Chemical factories dispose waste matters in streams, which contain many harmful metals like lead, cadmium, nickel, mercury, etc. Due to excessive use of underground water, the water level goes down. As a result, the amount of certain toxic elements like arsenic, fluorine increases. All these elements cause water pollution and turns potable water unfit for human use.
Indiscriminate use: The pond water in village areas is used indiscriminately for washing, bathing purpose for both man and domestic animals. This practice makes the water polluted. Moreover, animal wastes, viz.-faecal matters of both livestock and human beings, urine disposed in open area can create huge environmental hazards:

9. Mention the types of water pollution. Explain the effects of water pollution on human health.

Ans. Types of water pollution

Based on the source, water pollution can be classified into five categories. These are [1] Underground water pollution, [2] Marine water pollution, [3] River water pollution, [4] Lake water pollution and [5] Pond water pollution.

Effects of water pollution on human health

[1] The harmful effects of using polluted or contaminated water while drinking, cooking, bathing, washing hands, rinsing mouth, etc. are mentioned in the next table.

Types of pathogens	Name of diseases
1. Viruses	Viral hepatitis A and E, polio, diarrhoea in babies, etc.
2. Bacteria	Typhoid, cholera, bacillary dysentery, etc.
3. Protozoa	Amoebiasis, giardiasis, etc.
4. Worms	Taeniasis, ascariasis, etc.

[2] Different elements like mercury, cadmium, lead, copper, nickel, arsenic, iron, chlorine, etc. cause moderate to severe nervous, gastroenteric, blood and skin-related diseases. [3] Excess fluorine in drinking water causes allergy, renal impairment, bone deformity and form permanent brown layer on teeth.

10. Describe the harmful effects of soil pollution.

Ans. Harmful effects of soil pollution

Different harmful effects of soil pollution are mentioned below.

Effect on human health: Soil pollution has many harmful effects on human health. These are as follows-
1. Infection by pathogens: Number of pathogens increases faster in polluted soil. These pathogens can enter into human body directly or by any vector like flies, cockroaches, rats, etc. Clostridium tetani is an edaphic pathogen that causes tetanus. Clostridium perfringens enters into human body through wounds to cause gas-gangrene. Spores of Aspergillus sp., cause a disease called aspergillosis.
2. Decrease in productivity of food: Fertility of soil is inversely proportional to the pollution level of the soil, i.e. as a soil becomes more polluted, its fertility decreases. Therefore, soil pollution is one of the most noteworthy causes of food scarcity.
Biomagnification: Gradual increase in the content of any pollutant through food chain from lower to upper trophic level is called biomagnification. It occurs in the following two ways—
1. Bioaccumulation: Certain non-biodegradable pollutants can’t be metabolised within animal body. Instead, these are accumulated in adipose tissues of those animals. In course of time, content of these pollutants reaches a fatal limit. This is called bioaccumulation.
2. Flow of pollutants through trophic level: Prey and predators remain interconnected in a food chain. The pollutant accumulated in any trophic level is transferred to the next higher trophic level through food chain. By this process, maximum quantity of pollutants reach the topmost trophic level. The biomagnification of DDT is mentioned in the following flowchart as an example.

11. What is noise pollution? Mention a few causes of noise pollution.

Ans. Noise pollution

Any undesirable and disturbing high frequency or high intensity noise, that is harmful for human health as well as for wildlife, is called noise pollution.

Causes of noise pollution

Noise pollution is caused by different agents, which are as follows.

Motor vehicles: Number of motor vehicles increases in accordance with global population. We see huge concentration of traffic especially in urban areas. The sound created by horns and engines of motor vehicles such as motorcycle, car, bus, lorry, tram, tempo, etc., taking off and landing of aircrafts, etc. well exceeds the permissible noise limit of 65 dB in commercial areas by Central Pollution Control Board (CPCB).
Industrial factories: Friction of different instruments, sound of engines, hammering of metals create very high intensity sound. CPCB has fixed the sound intensity at an average of maximum 75 dB for 8 hours in a day for industrial zones. Whereas, much more sound is created by different factories and mechanical workshops resulting in noise pollution.
Electrical appliances: Different domestic electrical appliances like mixture grinder, vacuum cleaner, washing machine, power generators create high intensity sound. Besides these, loudspeakers, high watt sound systems, radio, TV, etc. an generate harsh sound above the permissible limit of noise of 55 dB in residential areas and create noise pollution.
Fire crackers: As a powerful firecracker bursts, it suddenly creates a very high intensity sound reaching up to 150 dB or above. This type of polluting sound may damage the cochlea of inner ear and can develop permanent deafness, called acoustic trauma.

12. Mention the adverse effects of noise pollution on human and other animals. Part question, What are the harmful impacts of sound pollution can exert on the ears and heart in human body?

Ans. Adverse effects of noise pollution on man

The adverse effects of noise pollution on human are mentioned below.

Effect on ear: [A] Hearing a high frequency sound for a prolonged period causes the soundsensory cells of the organ of Corti inactive. In this case, the person may gradually become deaf. Drivers of metro rail face similar problem. [B] A sudden sound of more than 150 dB may rupture the eardrums and may damage the cochlea to cause permanent deafness. Survivors of bomb blast often face similar consequences.
Effect on heart: [A] Hearing high intensity noise causes excitement which in turn increases heartbeat. [B] Continuous hearing a noise above 90 dB increases systolic pressure. [C] Prolonged listening to a sound above 60 dB may cause myocardial infarction to the listener. [D] Hearing high intensity sound for some time increases the chance of heart attack.
Other effects: [A] Noise pollution leads to mental depression. [B] High intensity sound causes lack of concentration. [C] It may lead to insomnia. [D] Noise curtails physical ability and enhances fatigue. [E] A person may become ill-tempered with the effect of noise pollution.

Adverse effects of noise pollution on animals

The adverse effects of noise pollution on animals are mentioned below.

Deafness: A high intensity sound may cause deafness in animals.
Hampered reproduction: Noise change the reproductive behaviour of many animals. Population of birds and several other animals has shrinked significantly due to noise pollution.
Effect on foetal growth: It is experimentally proved that high intensity sound restricts foetal development in rats.

Short Answer Type Questions

1. What is meant by environmental pollution?

Ans. The state of environment, when different materials, harmful for normal existence of plants and animals, reach beyond admissible level, is called environmental pollution. Presently this is the most alarming environmental issue all over the world.

2. What is meant by pollutants?

Ans. The substances which cause undesirable changes in the environment by harming the biosphere, are called pollutants. Huge amount of pollutants on earth is the main cause of environmental pollution. Example-Sand particles, CO₂, NO₂, SO₂, lead, mercury, pollen grains, etc.

3. Into how many types did environmentalist E P Odum classify the environmental pollutants?

Ans. E P Odum, the famous environmentalist, classified environmental pollutants into two main types. These are-[1] Biodegradable pollutants and [2] Non-biodegradable pollutants.

4. What is meant by biodegradable pollutants?

Ans. There certain are complex polluting compounds, which are degraded easily into simple compounds by biological decomposition with the help of bacteria and other microbes. These are known as biodegradable pollutants. Example-Household organic wastes.

5. What is meant by non-biodegradable pollutants?

Ans. There are certain complex, polluting substances which do not degrade easily into simple compounds by biological decomposition. These compounds are recycled in food chain for very long time. These are known as nonbiodegradable pollutants. E.g.-DDT, polythene.

6. What are primary air pollutants?

Ans. The air pollutants, which are produced directly by natural process or man-made and mix in atmosphere to cause air pollution, primary air pollutants. Example-CO₂, SO₂, suspended particulate matters, ozone, etc. are called

7. What are secondary air pollutants?

Ans. Several primary air pollutants present in the atmosphere undergo reactions among each other in presence or absence of sunlight to produce more harmful polluting substance. These are called secondary air pollutants. E.g.-Sulphuric acid, nitrous acid, smog, peroxyacetyl nitrate, etc.

8. What is meant by polluted air?

Ans. The air, which contains pollutants like carbon monoxide, sulphur dioxide, different oxides of nitrogen, dust particles, hydrogen sulphide, etc. beyond admissible limit is called polluted air. It has harmful effects on human beings, animals and plants. Polluted air is a major issue of health concern in all developing countries.

9. What is meant by pollution free air?

Ans. The air, which is either pollutant-free or may contain a few of it well below admissible limit, is called pollution free air. Pollution free air is abundant in seacoasts and hilly areas.

10. What is ozone hole?

Ans. Chloroflurocarbon (CFC), halone, etc. released due to human activities break the ozone gas of the ozonosphere into O₂ making holes in the ozone layer. It is called ozone hole. The decrease of concentration of ozone layer is called ozone depletion.

11. Write the harmful effects of ozone hole.

Ans. Some of the harmful effects of ozone hole are [1] The UV ray of sunlight easily enter into the earth through the ozone hole. This UV ray causes skin cancer, cataract, etc. [2] UV ray destroys certain good bacteria of soil and air causing loss of crop production.

12. How is PAN produced in atmosphere?

Ans. In presence of sunlight, nitrogen dioxide reacts with hydrocarbons in the atmosphere to produce a colourless gas called PAN or peroxyacetyl nitrate. PAN is a secondary air pollutant causing irritation in eye, inflammation in respiratory system, especially in trachea, etc.

13. How does the automobile exhaust cause air pollution?

Ans. Automobile exhaust contains various harmful gases like carbon monoxide, carbon dioxide, nitrogen oxides, etc. All these gases cause air pollution. About 40% of total air pollution occurs due to the gases released from automobiles.

14. What is greenhouse effect?

Ans. Accumulation of gases like carbon dioxide, nitrous oxide, methane, chlorofluorocarbon, water vapour, etc. creates a gaseous layer in the atmosphere. This layer does not allow heat to escape from earth. Instead, it is reflected back to the earth surface continuously. This heat increases the temperature of earth’s atmosphere. This is known as greenhouse effect.

15. What are the different components of SPM?

Or, Give some example of common SPM.

Ans. SPM are very fine, amorphous particles, those are light enough to be suspended in air. These include pollen grains, fly ash, coal dust, soil dust, metal oxide particles, asbestos particles, unburnt carbon particles or soot, etc.

16. Mention various sources of SPM.

Ans. Some common sources of SPM in the atmosphere are-automobile exhaust, emission of factory chimneys, soil dust, dust from agricultural field, carbon dust from oil refineries, pollen grains from forests.

17. What are the harmful effects of SPM?

Ans. Different harmful effects of SPM are as follows-[1] SPM lesser than 10 μm can enter into the blood stream and can cause cancer. [2] SPM cause harm to nasal passage, pharynx, trachea and lungs. These substances cause bronchitis, laryngitis, tuberculosis, black lung disease, lung cancer, etc. [3] Change of heart rate and heart attack are some of the severe harmful effects of SPM. [4] SPM also creates smog which in turn reduces visibility and causes acid rain.

18. What is aerosol?

Ans. Several very fine, colloidal, solid particles, microdroplets of volatile liquids and vapours remain suspended in the air. These are called aerosols. These particles have diameter of less than 1μ. Dust, smoke, etc. are some examples of aerosols.

19. What is smog?

Ans. In presence of sunlight, air-borne hydrocarbons undergo a photochemical reaction with nitrogen oxides those have been released especially by automobiles to produce a smoky gaseous substance in the atmosphere. This smoky gas mixes with atmospheric moisture to make a greyish misty surrounding which blurrs our vision. This is called smog. Simply we can say that smog is a mixing of fog and smoke.

20. Mention two causes of increase in carbon dioxide level in the atmosphere.

Ans. Two causes of increase in carbon dioxide level in the atmosphere are as follows-[1] Excessive burning of different fossil fuels like coal, petroleum, mineral oils, natural gases, etc. [2] Indiscriminate deforestation also increases carbon dioxide level in atmosphere.

21. How does acid rain cause damage to Taj Mahal and other marble architectures?

Ans. The chief component of marble is calcium carbonate (CaCO₃). When these marble objects are exposed to nitric acid and sulphuric acid of acid rain, calcium carbonate reacts with these acids to form calcium nitrate and calcium sulphate respectively. As a result, the marble gets corroded and loses its lustre. This is called ‘stone leprosy’ or ‘stone cancer.

22. Name two devices used to remove air pollutants.

Ans. Certain instruments are now used to remove various pollutants from air. Two of the common air pollution-controlling devices are electrostatic precipitator and catalytic converter.

23. What is water pollution?

Ans. Water pollution is the contamination of water bodies (e.g.-lakes, rivers, oceans, underground water, etc.). It occurs, when pollutants are directly or indirectly discharged into waterbodies without adequate treatment to remove harmful compounds from water. Consumption of this polluted water causes various health hazards in different organisms including human beings.

24. Mention two causes of water pollution.

Ans. Two causes of water pollution are- -[1] Mixing of agricultural wastes including fertilisers, pesticides, herbicides, etc. [2] Mixing of industrial wastes including various toxic chemicals, boiling water, radioactive wastes, etc. in waterbodies.

25. What is meant by physical pollution of water?

Ans. The pollution, in which water of any waterbody becomes turbid, foul smelling with a bad taste due to accumulation of different polluting substances, is called physical pollution of water. Physical pollution makes water unsuitable for drinking and survival of several aquatic species.

26. What is algal bloom?

Ans. The process or situation in which a large and excessive growth of algae on or near the surface of fresh and saline waterbodies naturally or as a result of the oversupply of nutrients from organic pollution. Harmful effects of algal bloom are blocking of sunlight, depletion of oxygen levels and sceretion of toxins in the water. Thus algal bloom very often results into eutrophication of waterbodies.

27. What is eut eutrophication?

Ans. Water pollutants often contain inorganic phosphates and nitrates, which, when get mixed to any stagnant waterbody increase nutrient level of the water. In this nutrient-rich waterbodies, different phytoplanktons grow very fast, which results into deterioration of water quality and oxygen level. This condition is called eutrophication.

28. Mention few characteristic features of eutrophic water bodies.

Ans. Few characteristic features of eutrophic waterbodies are as follows-[1] Presence of excess nutrients in water and development of algal bloom. This turns the colour of water into green. [2] Eutrophic waterbodies have a reduced level of dissolved oxygen which causes death of aquatic animals, mainly fishes. [3] Decomposition of algal bodies produces a toxic substance, viz, strychnine (a toxic substance) which reduces biodiversity in aquatic ecosystem.

29. Why does oxygen level decrease in eutrophic waterbodies?

Ans. In eutrophic waterbodies, the algal bloom occurs very fast. After death of these algae and other planktons, huge amount of organic matters decompose and accumulate in the floor. Large quantity of dissolved oxygen is consumed during this decomposition process by decomposing bacteria and that is why, oxygen level decreases in eutrophic waterbodies.

30. Name the pollutants present in crop field wastes.

Ans. The pollutants present in crop field wastes are-[1] Insecticides like DDT, BHC, etc., [2] Nitrate and phosphate-containing different inorganic fertilisers.

31. What does agricultural runoff mean?

Ans. The excess fertilisers, pesticides, crop remnants, soil particles, etc. are washed off from the crop fields during heavy rain or overflooding of irrigation water. This is called agricultural runoff. Agricultural runoff is one of the most principal agents of water pollution.

32. What does BOD or biological oxygen demand mean?

Ans. After mixing of industrial wastes in any waterbody the population of planktons and microorganisms increases. For respiration, these organisms absorb excess oxygen from the waterbody. As a result, a need for dissolved oxygen increases in the water which is called BOD or Biological Oxygen Demand.

33. What is COD? What is its significance?

Ans. COD: The Chemical Oxygen Demand or COD is an indicative measure of the available amount of the oxygen consumed during a reaction in a definite measured solution. SI unit of COD is mg/L.

Significance: COD is a measure of water and waste water quality. It helps in deciding the disposal of organic and inorganic effluents of domestic and industrial origin.

34. How does infection of cholera occur? Mention its symptoms.

Ans. Infection of cholera: Cholera is a bacterial disease. Its causative agent, Vibrio cholerae is a water-borne bacterium. The person may get infected with cholera when consumes the water directly or indirectly contaminated with Vibrio cholerae.

Symptoms: The symptoms of cholera are severe diarrhoea, vomiting followed by extreme dehydration and even death.

35. How does infection of typhoid occur? Mention its symptoms.

Ans. Infection of typhoid: Typhoid is a bacterial disease. The causative agent is a water-borne bacterium, Salmonella typhi. The person may get infected with typhoid when intakes the water contaminated with Salmonella typhi.

Symptoms: The symptoms of typhoid are high fever with headache, abdominal pain and diarrhoea.

36. Mention two main causes of soil pollution.

Ans. Two main causes of soil pollution are as medical follows-[1] Pathogenic germs-The wastes and municipal wastes contain thousands of germs, which pollute soil. [2] ChemicalsChemical fertilisers, pesticides, industrial and household wastes contain different harmful nonchemicals biodegradable that cause soil pollution.

37. How does atomic pollution occur in soil?

Ans. After atomic explosion or by dumping of byproducts from atomic reactors and atomic power plants, different radioactive substances mix in soil. By this process, atomíc pollution occurs in soil.

38. Which type of pesticides cause maximum soil pollution?

Ans. Organochlorine pesticides, like-DDT, BHC, aldrin, etc. cause maximum soil pollution. These are highly stable compounds, which retain their harmful effect for long time within the soil without any degradation.

39. What is meant by bioaccumulation?

Ans. Bioaccumulation is the net accumulation of harmful substances in an organism from all the resources, like-water, air or food. Certain pollutants, enter into animal bodies through food and do not undergo metabolic changes. Without being excreted, these compounds accumulate in certain animal tissues, especially the adipose tissues. In course of time, the quantity of these compounds increases in many folds in the animal bodies causing bioaccumulation.

40. How does fly ash cause environmental pollution?

Ans. Fly ash causes environmental pollution in two ways, which are as follows-[1] Soil pollutionFly ash does not contain any nutrient. If this dust is piled to fill up a low land, the soil underneath it becomes infertile. [2] Air pollution-The particles of fly ash are very light. Hence are flown away by wind. As a result it adds SPM in air.

Very Short Answer Type Questions

Multiple Choice Questions & Answers [MCQ]

1. The main greenhouse gas is-

A. Oxygen

B. Ozone

C. Carbon dioxide

D. Chlorofluorocarbon

Ans. C

2. The gas emitted from refrigerator and aircondition industries is-

A. N₂O

B. SO₂

C. CFC

D. H₂O₂

Ans. C

3. Normal amount of atmospheric carbon dioxide is about-

A. 0.1%

B. 0.01%

C. 0.03%

D. 0.3%

Ans. C

4. Which of the following is not a greenhouse gas?

A. Methane

B. Oxygen

C. Carbon dioxide

D. Nitrogen dioxide

Ans. B

5. The main source of methane in the environment is-

A. Anaerobic respiration by microorganisms in marshy land

B. Bacterial decomposition in hot springs

C. Volcanic eruption

D. Lightning

Ans. A

6. Which of the following is fossil fuel?

A. Methane

B. Mineral oil

C. Coal

D. Both B & C

Ans. D

7. Gas produced by incomplete oxidation of fossil fuel is-

A. Nitric oxide

B. Hydrogen sulphide

C. Carbon monoxide

D. Chlorofluorocarbon

Ans. C

8. A poisonous breath-choking gas is-

A. Carbon dioxide

B. Nitrogen

C. Oxygen

D. Carbon monoxide

Ans. D

9. Ozone layer is present in the-

A. Troposphere

B. Stratosphere

C. Exosphere

D. Mesosphere

Ans. B

10. The gas that causes maximum damage to the ozone layer is—

A. Carbon dioxide

B. PAN

C. Chlorofluorocarbon

D. Carbon monoxide

Ans. C

11. CFC gas is emitted from-

A. Oil refineries

B. Refrigerator factories

C. Automobiles

D. Smog

Ans. B

12. The microorganisms of wetlands produce-

A. Methane

B. Aerosol

C. Elinver

D. Butane

Ans. A

13. The pollutant emitted from foam, mattress factories is-

A. PAN

B. Lead

C. CFC

D. NO

Ans. C

14. The plant part responsible for air pollution is-

A. Flower

B. Fruit

C. Leaves

D. Pollen grains

Ans. D

15. Full form of PAN is-

A. Para acetyl nitrate

B. Peroxyacetyl nitrate

C. Peroxy acid nitrate

D. Para acedic nitrogen

Ans. B

16. CO₂, SO₂ and NO are-

A. Primary pollutant

B. Secondary pollutant

C. Tertiary pollutant

D. None of the above

Ans. C

17. PAN, SO₃, HNO_X are-

A. Primary pollutant

B. Secondary frllutonl

C. Portial pollutant

D. Not pollutant

Ans. B

18. Example of SPM is-

A. Lead

B. Pollen grain

C. Aerosol

D. Plastic

Ans. B

19. Which type of pollution is caused by SPM?

A. Air pollution

B. Soil pollution

C. water pollution

D. Sand pollution

Ans. A

20. The diameter of aerosol is-

A. Less than 1 μ

B. 1.5 μ

C. 5-15 μ

D. More than 15 μ

Ans. A

21. The main components of acid rain are-

A. Hydrochloric acid and hydrofluoric acid

B. Maleic acid and formic acid

C. Sulphuric acid and nitric acid

D. Citric acid and tartaric acid

Ans. C

22. The gas which is abundant in industrial area is-

A. Oxygen

B. Argon

C. Sulphur dioxide

D. Neon

Ans. C

23. A harmful effect of sulphur dioxide is-

A. Inflammation of respiratory tract

B. Black spots on skin

C. Pancreatic disease

D. Gastric ulcer

Ans. A

24. Natural source of sulphur dioxide is –

A. Waterbodies

B. Lightning

C. Volcanoes

D. Chemical factories

Ans. D

25. Which of the following is the main source of sulphur dioxide in air?

A. Thermal power plants

B. Hydro power plants

C. Atomic power plants

D. Chemical industries

Ans. A

26. Due to acid rain, maximum damage occurs to-

A. Wooden houses

B. Glass wares

C. Marble sculptures

D. Porcelain articles

Ans. C

27. The diseases associated with air pollution-

A. Diarrhoea, typhoid, hepatitis

B. Hepatitis, bronchitis, deafness

C. Bronchitis, asthma, lung cancer

D. Lung cancer, polio, malaria

Ans. C

28. In underdeveloped countries, water pollution is caused mainly due to-

A. Human and cattle wastes

B. Thermal power plants

C. Industrial by-products

D. Atomic power plants

Ans. A

29. An example of biochemical water pollutant is-

A. Brick

B. Sand

C. Stone

D. Detergent

Ans. D

30. A water-insoluble pollutant is-

A. Hydrogen sulphide

B. Salt

C. Arsenic

D. Plastic

Ans. D

31. The component of detergent that causes maximum water pollution is-

A. Alkali

B. Sulphate

C. Phosphate

D. Nitrate

Ans. B

32. The metallic particles, which cause maximum water pollution, are-

A. Lead and mercury

B. Sodium and potassium

C. Iron and copper

D. Magnesium and silver

Ans. A

33. Living water pollutants are-

A. Wood pieces

B. Pebbles

C. Worms, protozoans, aquatic insects

D. Insecticides and detergents

Ans. C

Answer in a single word or sentence

1. Which substances cause maximum air pollution?

Ans. Automobile exhausts and gases emitted from chemical industries cause maximum air pollution.

2. Name two greenhouse gases.

Ans. Chlorofluorocarbon (CFC) and methane (CH₄) are two greenhouse gases.

3. Which are the main sources of air polluting hydrocarbons?

Ans. Combustion of fossil fuel and emission from chemical factories are the main sources of air polluting hydrocarbons.

4. Which are the two main air pollutants in urban cities?

Ans. Hydrocarbons and aerosols are the two main air pollutants in urban cities.

5. What is the main cause of air pollution in metro cities?

Ans. Automobile emission is the main cause of air pollution in metro cities.

6. What is fly ash?

Ans. Fine solid particles of ashes, dust and soot produced from burning fossil fuels, likecoal, mineral oils in thermal power plants or paper are called fly ash.

7. What is the name of the gas responsible for Bhopal gas tragedy?

Ans. The gas which is responsible for Bhopal gas tragedy is methyl isocyanate.

8. Name the fine particulate matters liberated due to incomplete combustion of petroleum from oil refineries.

Ans. Petcoke dusts are the fine particulate matters liberated due to incomplete combustion of petroleum from oil refineries.

9. How do SPM cause harm to human respiration?

Ans. The SPM, suspended in air, cause irritation in pharynx and breathing distress.

10. Which pollutant of automobile exhaust prevents haemoglobin formation in blood?

Ans. Lead, liberated from automobile exhaust prevents haemoglobin formation in blood.

11. Name a symbiotic association that acts as bio-indicator of air pollution.

Ans. Lichen is a symbiotic association that acts as bio-indicator of air pollution.

12. Which pollutant reduces chlorophyll content in green plants?

Ans. Sulphur dioxide

13. Name two gases responsible for acid rain.

Ans. Two gases responsible for acid rain are sulphur dioxide and nitrogen dioxide.

14. Name two famous architectures in India, which are vulnerable to acid rain.

Ans. The Taj Mahal of Agra and the Victoria Memorial of Kolkata are two famous architectures in India, which are vulnerable to acid rain.

15. Which gas is emitted during volcanic eruption?

Ans. Sulphur dioxide

16. What is the full form of COPD?

Ans. The full form of COPD is Chronic Obstructive Pulmonary Disease.

17. Mention two adverse effects of carbon monoxide on human health.

Ans. Two adverse effects of carbon monoxide on human health are breathing distress and fatal blood toxicity.

18. Name a gas which causes lung cancer.

Ans. Sulphur dioxide gas causes lung cancer.

19. Name the harmful component that enters into lungs during smoking.

Ans. During smoking, the harmful component named chlorobenzene enters into lungs.

20. Which disease often occurs among the miners of coalmine?

Ans. Black-lung disease often occurs among the miners of coalmine.

21. Name three main types of insecticides.

Ans. Organochlorine, organophosphate and carbamate

22. What is the full form of DDT?

Ans. The full form of DDT is dichlorodiphenyltrichloroethane.

23. Name two organochlorine insecticides.

Ans. Two organochlorine insecticides are DDT (Dichlorodiphenytrichloroethane) and BHC (Benzene hexachloride).

24. Name two water-insoluble bio-pollutants.

Ans. Dry leaves and algae

25. What is sewage?

Ans. The domestic waste matters and human excreta, which are discharged through municipal waste disposal system, are collectively called sewage.

26. Name two water-borne viral diseases.

Ans. Hepatitis A and polio

27. Name two water-borne bacterial diseases.

Ans. Cholera and bacillary dysentery are two water-borne bacterial diseases.

28. Name two water-borne protozoan diseases.

Ans. Amoebiasis and giardiasis are two waterborne protozoan diseases.

29. Name two water-borne helminthic diseases.

Ans. Taeniasis and ascariasis are two water-borne helminthic diseases.

30. Name the bacterium which causes typhoid.

Ans. Salmonella typhi

31. Name the bacterium which causes cholera.

Ans. Vibrio cholerae

32. Name two harmful toxins produced by algae.

Ans. Neurotoxin and hepatotoxin

33. What depth of a tube well is unlikely to contain arsenic?

Ans. A tube well with a depth of 500-600 ft is unlikely to contain arsenic.

34. What is the acceptable limit of fluorine in drinking water in India?

Ans. The acceptable limit of fluorine in drinking water in India is less than 1.2 mg/L.

35. Which salt is predominant in seawater?

Ans. Sodium chloride is predominant in seawater.

Fill in the blanks

1. From refrigeration industry ………. is evolved.

Ans. CFC

2. ……….. is a nitrogenous greenhouse gas.

Ans. Nitrous oxide (N₂O)

3. By the combustion of fossil fuels, a greenhouse gas named ……….. is liberated in the atmosphere.

Ans. CO₂

4. An inflammable greenhouse gas produced from paddy fields is ………

Ans. Methane (CH₄)

5. The fine droplets of smokes, ashes, dusts, pollen grains, etc. suspended in air collectively called ……… which cause various lung diseases.

Ans. Suspended particulate matters (SPM)

6. The air-borne particulate matters less than a diameter of ……….. are called aerosols.

Ans. 1 μ

7. …………. gas is produced due to the decomposition of garbage.

Ans. Methane

8. The pH of water bodies ………… after acid rain.

Ans. Reduces

9. The architectures built of ………… and limestone are damaged by acid rain.

Ans. Marble

10. The ………… present in marble reacts with acid rain to produce sulphate and nitrate.

Ans. Calcium carbonate

11. SO₂, NO_X, etc. increase the occurrence of ………… among people living in industrial area.

Ans. Asthma

12. A respiratory disease caused due to air pollution is …………

Ans. Bronchitis/ Asthma

13. The miners of coal mine often develop …………. disease.

Ans. Black lung

14. The disease caused due to squeezing of the trachea is called …………

Ans. COPD

15. Pollution due to silica fibres is responsible for ………… disease.

Ans. Silicosis

16. DDT is an ………….. pesticide.

Ans. Organic

17. ………… is a toxic material released by algae.

Ans. Neurotoxin

18. Salmonella typhi causes …………. disease.

Ans. Typhoid

19. Cholera is caused by the …………. bacterium.

Ans. Vibrio cholerae

20. The pathogen causing amoebiasis is …………..

Ans. Entamoeba histolytica

State true or false

1. Methane is a greenhouse gas.

Ans. True

2. O₃ is used in aerosol spray.

Ans. False

3. In SPM disease, the trachea is inflamed.

Ans. True

4. Acid rain is caused by SO₂ and NO₂ gases formed due to air pollution.

Ans. True

5. The Taj Mahal is adversely affected by acid rain.

Ans. True

6. Black lung disease is a water-borne disease.

Ans. False

7. Decrease in pH of waterbodies hampers the ecological balance.

Ans. True

8. Aldrin is an inorganic pesticide.

Ans. False

9. High fever is significant symptom of cholera.

Ans. False

10. Arsenicosis is caused due to mercury pollution.

Ans. False

TOPIC – 3

ENVIRONMENT AND HUMAN POPULATION

SUMMARY

Human population, at present, is growing at a rate of 2% a year and to meet the demands of rapidly growing population tremendous progress has been made by means of technological innovations in the fields of agriculture and industry. This has resulted in the unlimited exploitation of natural resources, degradation of environment, global warming, etc. Also increased uses of fossil fuels resulted in irregular rainfall, acid rains, ozone depletion.
The disorders of the respiratory system are mainly caused due to degradation of the air quality or presence of air pollutants. One such disease is asthma. Particles of dried excreta, pollen, animal dander, dust particles, fungus causes allergic asthma. Breathing trouble is the main symptom of this disease. Asthma can also occur due to bacterial infection of the bronchi, bronchioles and lungs.
Bronchitis is mainly an infectious disease caused by virus and bacteria but small chemical particles, acid fumes, smoke increase its intensity. It causes inflammation of bronchus and bronchioles. This disease is seen more in the workers involved in firebrigade, metal-moulding, coal mining, grain handling, etc.
Uncontrolled cell division causes cancer. Smoking, herbicides, radioactive agents, intake of tobacco, insecticides act as carcinogen and induce cancer. Oncogenes play vital roles in cancer formation.

Long Answer Type Questions

1. Describe the effects of population explosion on environment.

Part question, What environmental problems may arise in a locality due to ever-increasing human population?

Ans. Effects of population explosion on environment

The effects of population explosion on environment are described below.

Squeezing of forest area: To provide food for a large population, portions of forestlands are encroached and are converted into agricultural lands or residential areas. This practice is directly affecting the environmental balance.
Occurrence of natural calamity: Deforestation increases the concentration of CO₂ in atmosphere resulting in greenhouse effect. The increased heat may cause excess cloud formation and heavy rainfall in one area and drought in another place. Surface soil is blown away in dry climate and during rain the runoff water carries huge amount of soil from the deforested land. The rivers hold this extra soil and lose their depth. During rain, such rivers swell up and the surrounding areas become flooded.
Loss of soil fertility: To meet the need of extra food grains, a land is ploughed several times in a year for cultivation of crops. This practice reduces the fertility of soil. To get better yields, these fields are applied with different chemical fertilisers, which results into acidification of soil.
Effect on aquatic ecosystem: To provide animal protein to an extra large population, indiscriminate fishing is done. As a result, fish population decreases abruptly and ecological balance of water bodies is hampered.
Effect on mineral resources: To fulfil the need for energy, overpopulated countries extract more coal, petroleum, natural gases from underground reserve. Due to indiscriminate extraction of these fossil fuels, it has been predicted that the reserve will be finished within a few decades.
Increase in the pollution level: Overpopulated countries produce proportionately higher quantity of garbage and sewage. These matters increase environmental pollution. Extraction of water by deep tubewells pulls up the harmful salts from the underground layers of rocks. These salts contain deadly elements like arsenic, fluoride, etc. which cause water pollution.
Effect on society: In densely populated countries, all children do not get the chance to get educated. As a result, many individuals remain illiterate. Illiteracy is the main cause of poverty, joblessness, criminal activities within a society.

2. What is population explosion? How does population explosion affect human health?

Ans. Population explosion

Due to uncontrolled natality and less mortality rate, the size of a population may increase beyond the carrying capacity of an area. This leads to a situation which is known as population explosion.

Effects of population explosion on human health

The effects of increased population on human health are mentioned below.

Scarcity of food and malnutrition: Rapid increase in human population results into conversion of agricultural lands into residential areas. As a result, production of crops decreases significantly. That is why, people of any densely populated developing country do not get adequate quantity of food and suffer from malnutrition.
Industrial pollution and community health: To satisfy the various needs of living, populous countries give importance to establishing industries. Industrial smoke and sewages released from these factories contain various toxic pollutants. These chemical pollutants pollute air, water and soil. As a result, adverse effect is noticed in community health.
Sewage and garbage-related diseases: In populous countries, more garbage are dumped and more sewages are released. These materials increase the number of various disease-causing germs, which are then carried by vectors like flies, rats, cockroaches. etc. and cause many diseases like cholera, plague, malaria, etc. Sewages disposed in water pollute it. By this process, sewage and garbage pollute the environment and show harmful impact on human health.
Decrease in medical facilities: A developing country with high population does not have proportionate medical facilities. The patients have to wait long to get beds in hospitals. Similarly, they face shortage of medicines also. This deprives thousands of people of populous countries from medical treatment.

3. What is asthma? Explain the environmental causes of asthma.

Ans. Asthma

Due to inflammation of the inner mucosal layer of trachea and bronchioles, the lumen becomes narrow to restrict passage of respiratory air into the lungs. The distressed breathing caused due to this abnormality is known as asthma. It is a chronic respiratory disease.

Environmental causes of asthma

Asthma can be either allergic or non-allergic. The environmental causes for both types are described below.

Allergic asthma: Air pollution is the main cause of allergic asthma. Different allergens like dust particles, pollen grains and several other suspended particles enter into the respiratory tract. These matters stimulate immune system and increase the count of eosinophils in blood. Eosinophils and mast cells release chemical substances like histamine and leukotrienes in blood. In response to these chemicals, the inner mucosa of respiratory tubes becomes inflamed to make the lumens narrow. As a result, the person suffers from acute breathing distress.
Non-allergic asthma: Viral infection mainly causes this type of asthma. In this case the inner mucosa of bronchioles becomes inflamed to narrow the lumen of the air tubes. Formation of polyps in nasal passage may be caused due to environmental factors and causes asthma.

4. “Change of climate and global warming is a problem resulting from the increasing human population.”-Summerise what impacts it might exert on environment. “Children and adults both suffer with different respiratory problems during winter.”-Write two names of such problems and state one symptom of each of them.

Ans. Effect of change of climate and global warming on environment

Change of climate and global warming is a problem resulting from the increasing human population. Their effects on the environment are as follows-[1] Due to increased level of greenhouse gases in the environment, amount of atmospheric components are being changed. These gases increase global temperature, as a result polar ice is melting. Polar bear, polar fox, etc. are becoming endangered as they are losing their habitats. [2] Due to global warming sea water level is increasing, as a result land areas near sea are getting submerged. [3] Ecosystem is being destroyed due to global warming, biodiversity is also being decreased. Example-Great barrier reef of Australia is depleting gradually. [4] Climate change is causing harm to agriculture which in turn causing scarcity of food. [5] In altered temperature harmful germs are getting more active and causing diseases.

Two respiratory problems during winter found in children and adults

Problem	Symptom
1. Allergic asthma	Contraction of bronchioles causing severe breathing trouble.
2. Bronchitis	Cough and mucous secretion in the early morning.

5. The ever-increasing population in the different cities of India is creating the crisis of groundwater’-Support the statement with reasons on the basis of your experiences. (Madhyamik ’20] Write four effects of deforestation.

Ans. Reasons for crisis of groundwater

[1] Underground water level is decreasing due to excessive use of fresh water. Daily use of water by humans is the reason behind excess need of water. [2] Water crisis has been developed because of wastage of water e.g. continuous running of taps at households and municipal or rural water connections of a locality. [3] In urban areas construction works are taking place, filling ponds, due to which water can not be stored underground. This is also a reason of fresh water scarcity. Thus based on above mentioned points it can be clearly understood that the ever-increasing population in the different cities of India is creating the crisis of groundwater.

Effects of deforestation

Four effects of deforestation are-[1] Soil erosion and desertification, [2] Global warming, [3] Loss of biodiversity, [4] Changes in climatic conditions and change in pattern of rainfall.

6. Explain the role of environmental factors or toxins in causing cancer.

Part question, What environmental factors may cause cancer in human?

Ans. Role of environmental factors in causing cancer

Cancer is caused due to a combination of genetic and environmental factors. The role of environmental factors in causing cancer is mentioned below.

Pesticides and herbicides: Different pesticides, herbicides and radioactive substances enter into human body by different means and may cause cancer.
Environmental toxins: Scientists have revealed that different toxins have direct relation with cancer. These materials are known as carcinogens, which include nicotine, tar, carbon monoxide, hydrogen cyanide, etc. Certain carcinogens can cause stable change to the DNA structure. By this process, inactive proto-oncogenes are transformed into active oncogenes. Finally, these oncogenes change the cell character and trigger cancer.
Tobacco: Chewing tobacco is harmful for the body as it causes cancer. Tobacco contains nicotine, which act as a carcinogen and initiates cancer in mouth, throat and tongue. The cigarette smoke contains a potent carcinogen, called benzopyrine. This chemical, along with tobacco tar settles in alveoli and causes lung cancer.
Radioactive materials: The scientists working with radioactive matters remain exposed to α, β, and y particles. They are often attacked by cancer. Radon is a radioactive gas emitted from some mines. If any miner inhales it for a prolonged period, this gas may cause lung cancer.
Chemical pollutants: Dust of chromium and asbestos may cause lung cancer. Building construction workers are frequently exposed to asbestos dust. On the other hand, welders inhale fumes of chromium. Both of these materials promote lung cancer.
Effect of plastic: The workers of plastic factories inhale the fume of burnt plastic materials, which may cause cancer of liver and urinary bladder.

Short Answer Type Questions

1. What is census?

Ans. Counting of population and collecting a number data about lifestyle, health, educational, professional and financial status of all individuals of the national population is called census. In India, census is done after every ten years. The last census was done in 2011.

2. Mention two causes of population explosion in India.

Ans. Two causes of population explosion in India are as follows-[1] Illiteracy, poverty, superstition, early marriage, etc. cause population explosion in Indian society. [2] Development of communication system and advancement of medical science have reduced mortality.

3. which are the environmental barriers against population increase?

Ans. The environmental barriers against population increase are-[1] Scarcity of food, [2] Deficiency of water and habitat, [3] Occurrence of different diseases, [4] Epidemic and famine.

4. In ecology, what does carrying capacity mean?

Ans. The maximum number of living organisms, which a specific area can accomodate without any degradation of ecosystem, is called carrying capacity. A population, growing beyond carrying capacity, disturbs the ecological balance of an ecosystem.

5. Mention two disadvantages of population explosion.

Ans. Two disadvantages of population explosion are as follows-[1] Excessive utilisation of natural resources-Due to population explosion, the demand for water, food, shelter and clothing have increased to a great extent leading to scarcity of these resources. [2] Environmental pollution-Excessive population is the main cause of environmental pollution. By different human actions air, water, soil are being polluted.

6. What is, migration?

Ans. Movement of the members of a population from one place to another in search of favourable living condition, is known as migration. Migration directly affects the population density of a region.

7. What would be the environmental consequences as results of recurrent destruction of wetlands and depletion of quantity of agricultural lands?

Ans. Wetlands are full of biodiversity. These help in removing pollutants from water and also controls local environment. Due to overpopulation, civilisation and industrialisation these wetlands are getting destroyed. As a result water pollution is increasing and local biodiversity is decreasing.

Due to urbanisation, quantity of urban land is being depleted. As a result, worldwide food production is decreasing comparing to increasing human population.

8. Why does asthma occur?

Ans. Certain allergens like pollen grains, viruses bacteria, when enter into respiratory tract or blood cause allergic stimulation. As a result, the inner lining of tracheal, bronchial tubes become inflamed and the lumen of the respiratory tracts become narrower. This obstructs the flow of air into the lungs. Therefore, an individual suffers from breathlessness and the condition is known as asthma.

9. Mention the environmental factors which cause asthma.

Or, What are the causes of asthma?

Ans. Certain environmental factors cause asthma. These are-air-borne asbestos fibres, smoke from burnt coal and oil, pollen grains, excreta of mattress mites, spores of fungi, dusts, etc.

10. Mention the symptoms of asthma.

Ans. The symptoms of asthma are-[1] Coughing especially during night, [2] Chest congestion and wheezing, [3] Breathing trouble.

11. Mention the causes of chronic bronchitis.

Ans. Smoke is the main cause of chronic bronchitis. The welders, firemen, who are regularly exposed to smoke, often suffer from this disease. The smoke evolved from industrial factories, automobiles, motor or diesel and petrol engines are also responsible for this.

12. Write down the symptoms of bronchitis.

Ans. The symptoms of bronchitis are- -[1] Fatigue, [2] Mild fever, [3] Chest congestion and pain.

13. Why wetlands are called kidney of nature?

Ans. Wetlands have been called ‘Kidney of nature’ because of their ability to store, assimilate and transform harmful materials or contaminants lost from the land before they reach river or lakes. Like a gaint kidney, wetlands help to dilute and filter materials that could otherwise harm our lakes, river or other waterbodies.

14. What are carcinogens?

Ans. Carcinogens are those chemicals or radiations, which have the ability to cause cancer. Carcinogen exposure by inhalation, ingestion or absorption can result in the synthesis of abnormal DNA. As carcinogens change DNA structure permanently, these are treated as special mutagens.

15. What is the difference between malignant and benign tumour?

Ans. Both benign and malignant tumours are formed by uncontrolled cell division. A benign tumour does not cause harm to the body and can be cured by operation. But a malignant tumour is harmful to the body, as the cells can undergo metastasis by spreading to other organs or tissues to develop more tumours there.

16. Mention the characteristic features of malignant tumour.

Ans. Malignant tumour which causes cancer is characterised by cells that may spread through blood or lymph to different organs and tissues of the body and may develop other malignant tumours there. This event is known as metastasis. By this process, malignant tumours spread cancer to different organs of the body.

17. Mention two characteristic features of cancer cells.

Ans. Two characteristic features of cancer cells are as follows-[1] A cancer cell has a nucleus comparatively larger than normal. [2] The cancer cells lose the ability of intercellular contact. This is called contact inhibition.

18. Mention the cancer-causing agents produced by human activity.

Ans. Different human activities may produce several cancer-causing agents. These material include asbestos fibres, silica powder, formaldehyde, acetaldehyde, benzopyrine, monosodium glutamate, etc.

19. Name three carcinogens present in the smoke of cigarettes and bidis.

Ans. The smoke of cigarettes and bidis contain many potent carcinogens. Three of these are acetaldehyde, vinyl chloride and formaldehyde.

20. What are the causes of lung cancer?

Ans. Generally, lung cancer occurs due to environmental or genetic factors. In this case, uncontrolled cell division takes place in the epithelial cells of the pleural membrane or in the alveolar epithelium. Besides tobacco smoking, some environmental pollutants like asbestos fibres, chromium and smoke produced during burning of plastics and fumes from various factories may also cause lung cancer.

21. How does radon gas affect human health?

Ans. Radon is a harmful radioactive gas. It is emitted from mines. If miners inhale this for gas prolonged period, they would develop lung cancer.

22. What is asbestosis?

Ans. Asbestosis is a long term inflammation and scarring of the lungs due to asbestos fibre. Shortness of breath, persistent dry cough and chest tightness are some of the symptoms of asbestosis. It may lead to cancer.

Very Short Answer Type Questions

Multiple Choice Questions & Answers [MCQ]

1. The annual rate of increase in global population is about-

A. 1.2%

B..2.2%

C. 3.2%

D. 4.2%

Ans. A

2. Number of neonates born (UNFPA) globally in a year is approximately-

A. 100 million

B. 130 million

C. 150 million

D. 180 million

Ans. B

3. According to survey of United Nations, in 2025 global population will reach-

A. 5.8 billion

B. 6.8 billion

C. 8.2 billion

D. 9.8 billion

Ans. C

4. Excessive rate of increase in population is called-

A. Population expansion

B. Population development

C. Population explosion

D. Population contraction

Ans. C

5. The main cause of environmental problem in India is-

A. Shortage of resources

B. Scarcity of food

C. Lack of education

D. Population explosion

Ans. D

6. The present full form of UNFPA is-

A. United Nations Fund for Population Activities

B. United Nations Fund Population Authority

C. United Nations Financial Property Activities

D. United Nations Fund for Personal activities

Ans. A

7. By dividing the total number of individuals of a population of a country or any particular region with its total area, we get-

A. Population volume

B. Rate of population increase

C. Carrying capacity

D. Population density

Ans. D

8. The rate of conversion of agricultural land to residential area in India between 2001 to 2010 is about-

A. 4%

B. 3%

C. 2%

D. 1%

Ans. D

9. Uncontrolled growth of population is seen during –

A. Absence of biological power

B. A steady carrying capacity

C. Absence of environmental barriers

D. Presence of various environmental barriers

Ans. C

10. The factor that acts against population growth is-

A. Saturation point

B. Carrying capacity

C. Population pressure

D. Environmental pressure

Ans. D

11. 11th july is celebrated as-

A. World Environment Day

B. World AIDS Day

C. World Population Day

D. World Wetland Day

Ans. C

12. Population of an area declines due to-

A. Increase in natality

B. Increase in mortality

C. Immigration

D. All of these

Ans. B

13. The primary phase of a sigmoid growth curve is-

A. Log phase

B. Plateau phase

C. Lag phase

D. Exponential phase

Ans. C

14. Exponential growth represented byof a population is-

A. ‘J’ shaped graph

B. ‘S’ shaped graph

C. Hyperbolic graph

D. ‘I’ shaped graph

Ans. A

15. The percentage ratio of natality to mortality is known as-

A. Population density

B. Vital index

C. Total count

D. Population rate

Ans. B

16. Carcinogens can cause cancer because-

A They can destroy the immune system

B. They can transform DNA

C. They stop cell division

D. They enhance the microbial infection

Ans. B

17. The gas responsible for lung cancer is-

A. Radon

B. Carbon dioxide

C. Hydrogen

D. Nitrogen

Ans. A

18. Main cause of lung cancer is-

A. Weedicide

B. Asbestos

C. Smoking

D. Pesticide

Ans. C

19. The breathing distress caused by squeezing of trachea and bronchus is known as-

A. Emphysema

B. Asthma

C. Pneumonia

D. Atelectasis

Ans. B

20. If the amount of pollen grains, fungal spores and dust particles increase suddenly in the air, decide which of following problems may increase-

A. Tuberculosis

B. Asthma

C. Malaria

D. Dengue

Ans. B

21. The bacterium responsible for pulmonary tuberculosis is-

A. Mycobacterium

B. Streptococcus

C. E. coli

D. Staphylococcus

Ans. A

22. Uncontrolled cell division of the cells in lung causing abnormality in lung function indicates-

A. Pulmonary tuberculosis

B. Lung cancer

C. Emphysema

D. Cystic fibrosis

Ans. B

23. A chronic lung disease is-

A. Pneumonia

B. Asthma

C. Cancer

D. Flu

Ans. B

24. The lung disease, in which lung tissue cells are damaged weakening its expandability, is known as-

A. Cyanosis

B. Cystic fibrosis

C. Asthma

D. Emphysema

Ans. D

25. Cancer causing gene is called-

A. Transgene

B. Oncogene

C. Split gene

D. Jumping gene

Ans. B

26. Spreading of tumour cells to different parts of the body is known as-

A. Apoptosis

B. Metastasis

C. Hypostasis

D. Homeostasis

Ans. B

27. Which of the following is a cancer causing material?

A. Formaldehyde

B. Pollen grain

C. Arsenic

D. All of these

Ans. A

28. Active and passive smoking may cause-

A. Liver cancer

B. Lung cancer

C. Kidney cancer

D. Both A and B

Ans. B

29. Which of the following is not a cancer causing material or carcinogen?

A. Acetaldehyde

B. Radon gas

C. Formaldehyde

D. Pollen grain

Ans. D

30. Which of the following is known as nature’s kidney?

A. Wetland

B. Water spring

C. Sea

D. Hill

Ans. A

31. Biopsy of a tumour is done-

A. To treat cancer

B. To diagnose cancer

C. To develop cancer

D. To prevent cancer

Ans. B

32. Inflammation of mucous membrane of bronchi and bronchioles is known as-

A. Bronchitis

B. Tuberculosis

C. Asbestosis

D. Hypoxia

Ans. A

Answer in a single word or sentence

1. What does population mean?

Ans. Population means the total number of all individuals inhabiting a particular geographical area at a particular time.

2. How much increase in population has taken place in India in between 2001-2011?

Ans. In between 2001-2011, Indian population has increased by about 18.15 crores.

3. What is the population of India as per census of 2011?

Ans. 121.02 crores (approx)

4. What is the current (2016) population of the earth?

Ans. 7.4 billion (approx)

5. In which year did global population reach 1 billion?

Ans. In the year 1800, global population reached 1 billion.

6. What is the annual rate of increase in Indian population?

Ans. 1.26% (approx)

7. What is meant by population density?

Ans. The measurement of population per unit area is called population density.

8. What is meant by normal growth of a population?

Ans. The difference between natural natality and natural mortality of the individuals of a population of a specific area means natural growth of a population.

9. What would be the global population in the year 2050?

Ans. According to the prediction by United Nations, the global population may reach 8.9 billion in 2050.

10. What is the scientific study of human population known as?

Ans. Demography

11. How do you denote the highest rate of reproduction within a population, in presence of all limiting factors?

Ans. Biological potential

12. Name a factor which prevents a population to reach the highest possible growth.

Ans. Environmental barrier (diseases, natural calamity) prevents a population to reach the highest possible growth.

13. Which is the second most populous country in the world?

Ans. India

14. Which tissue of lungs is affected by cancer?

Ans. Epithelial tissue of bronchioles in lungs is affected by lung cancer.

15. Name the disease in which pleural membrane is inflamed.

Ans. Pleurisy

16. What are the allergy causing matters known as?

Ans. Allergens

17. Which type of white blood cell count is elevated in an asthma patient?

Ans. Eosinophil

18. What is tumour?

Ans. The cluster of cells that form a lump due to uncontrolled cell division, is called tumour.

19. How many types of bronchitis are there?

Ans. There are two types of bronchitis-[1] Acute bronchitis and [2] Chronic bronchitis.

20. Mention the two types of tumours.

Ans. Benign tumour and malignant tumour

21. Name two cancer causing agents.

Ans. Benzopyrine and ethyl methane sulphate

22. Give one example of a benign tumour.

Ans. A wart on body surface is an example of benign tumour

23. Which type of tumour is harmful?

Ans. Malignant tumour

24. Mention two environmental causes of allergy.

Ans. Dust and pollen grains

25. Which type of cancer is instigated by asbestos and chromium?

Ans. Lung cancer

Fill in the blanks

1. An effect of ever-increasing population is ……….. erosion.

Ans. Soil

2. Only ………… % of earth’s water reserve is fresh water.

Ans. 3

3. The drinkable water on earth is just ………… % of the total water reserve.

Ans. 1

4. The rate of shrinkage of agricultural land is the highest in economically ………. areas.

Ans. Developing

5. …………. is a chronic breathing-related disease.

Ans. Asthma

6. The fine droplets of smokes, ashes, dusts, pollen grains, etc. suspended in air collectively called ………… , which cause various lung diseases.

Ans. SPM or Suspended Particulate Matter

7. The main cause of lung cancer is …………

Ans. Smoking

8. ………… of certain plants are responsible for breathing distress.

Ans. Pollens

9. One of the main causes of oral cancer is ………… chewing.

Ans. Tobacco

10. The major cause of chronic bronchitis is …………

Ans. Smoke

11. Uncontrolled cell division leads to the fatal disease called ……….

Ans. Cancer

12. Spreading of cancer cells in different organs and tissues of the body is known as ………..

Ans. Metastasis

13. The cancer-causing agents are called …………

Ans. Carcinogens

14. ……….. is a carcinogenic radioactive gas.

Ans. Radon

15. World Cancer day is ………..

Ans. 4th february

16. Inflammation of bronchus is called …………..

Ans. Bronchitis

17. …………… gases cause global warming.

Ans. Greenhouse

TOPIC – 4

BIODIVERSITY AND CONSERVATION

SUB-TOPIC 4.1

IMPORTANCE OF BIODIVERSITY, BIODIVERSITY HOTSPOTDEPLETION OF BIODIVERSITY AND ENVIRONMENTAL PROBLEMS OF SUNDARBAN

SUMMARY

Variability of gene, species and ecosystem in land, water and air can provide variety of organisms. This variation is called biodiversity. India is one of the 12 mega diversity countries in the period.
Biodiversity is very important for various reasons. It is related to food production, medicine formation from variety of organisms. Infact it is essential in maintaining the ecological balance, help to increase rainfall and controlling climatic changes.
Biodiversity has a wide economic importance. It supply raw material for furniture, paper and also provide resin, wax, silk, fur, pearl etc. Infact it also has a great influence in painting, architecture, music, to entertain the people.
Regions that are rich in biodiversity, like Himalayas Western Ghats, the Indo-Burma region and the Sundaland (includes Nicobar group of islands) are called hotspots.
There are various reasons behind the depletion of biodiversity, like change in land pattern, extensive use of land for industry, house and agriculture, hunting, global warming, climatic change, invasion of foreign species, natural calamities, etc.
In recent decade, Sundarban has faced lots of problems like-destruction of mangrove plants, agricultural lands gets salty due to flood, scarcity of drinking water, scarcity of habitat, water pollution and above all increase in sea level submerge the whole area. All these calamities can destroy the ecological balance of Sundarban,

Long Answer Type Questions

1. Briefly explain the significance of biodiversity.

Ans. Significance of biodiversity

Significance of biodiversity are given below.

Ecological importance: In an ecosystem, all organisms are ecologically interdependent on each other. Extinction of an organism will increase or decrease the number of other organisms and will create ecological imbalance. Therefore, a rich biodiversity results in a stable ecosystem.
Environmental value: A rich biodiversity is the indicator of a pollution free environment. By controlling the environmental pollution the conservation of the biosphere can be maintained.
Economic importance: We are dependent on plants and animals for food, clothing, medicines and shelter. We get various types of food from different variety of plants. Other than food, we get wood, paper, fibres, gums, resins rubbers and various medicinally important alkaloids from plants. We extract honey, wax, silk, wool, leather, milk, meat and egg, from animals. Thus, biodiversity is essential for the survival of human beings.
Weather control: Biodiversity is essential to prevent environmental pollution and to control the weather. This process maintains the stability of the biosphere. The tropical rain forests absorb CO₂ and thus reduce greenhouse effect and global temperature. A forest increases moisture in the atmosphere by transpiration and thereby increases the chance of cloud formation and rainfall. Many plants absorb toxic elements and help to detoxify soil. Several plants and microbes increase nitrogen content of the soil and thus increase soil fertility,
Aesthetic beauty: Living organisms add natural beauty and liveliness on the earth.
Moral value: Every organism on the earth has the right to live. This concept was accepted by United Nations in the memorandum of the earth summit in Nairobi, 1982.

2. Mention the types of biodiversity. State the names and locations of the biodiversity hotspots in te the names and India.

Ans. Types of biodiversity

Biodiversity can be classified into three types. These are mentioned below.

Genetic diversity: Several chromosomal and genetic differences occur within a population, which create many structural and behavioral variations within the members of the same species. This is called genetic diversity.
Species diversity: Within a biotic community of a particular area, several species interact with each other. The structural and behavioral variation of the members of these species and the difference in relative abundance of all the species in a biotic community is known as species diversity.
Ecological diversity: The variety among the organisms, belonging to different interacting ecosystems within a vast geographical area is known as ecological diversity.

Indian biodiversity hotspots

The names and locations of the biodiversity hotspots in India are mentioned below.

Eastern Himalayas: The North-Eastern states like Sikkim, North Bengal, Assam, Arunachal Pradesh are included under this hotspot. Due to the abundance of ancient flowering plants in these areas, Eastern-Himalayas hotspot is known as ‘cradle of speciation.
Indo-Burma: Other North-Eastern states like Manipur, Tripura, Mizoram, Meghalaya, Nagaland and south Assam belong to the Indo-Burma hotspot region.
Western Ghats and Sri Lanka: The hilly regions of Western Ghat in Gujarat, Maharashtra, Karnataka and Kerala belong to this hotspot region.
Sundaland: It comes under the Asia-Pacific region. The Nicobar group of islands belong to this hotspot region.

3. Explain the causes of depletion of biodiversity.

Or, Assess the causes of depletion of biodiversity with proper examples.

Ans. Causes of depletion of biodiversity

The causes of depletion of biodiversity are explained below.

Change in utilisation of land: Due to increased population pressure, the forest areas are cleared and converted into residential or industrial areas. Laying of roadways and railway tracks through forest land is squeezing the natural habitat of wild animals and plants. Indian elephant, mountain gorilla, orangutan, red panda, etc. species are facing extinction due to habitat loss.
Climatic change and global warming: Indiscriminate felling of trees increases CO₂ level in the atmosphere. Excess CO₂ causes greenhouse effect and increase atmospheric temperature. Many animals cannot adapt in this changed environment and become extinct. Due to global warming, the glaciers of polar region are melting. This results into increase in sea level. As a result, the delta of Sundarban is going under seawater.
Pollution: With the modernisation of life and industrialisation, environmental pollution has increased greatly. Many species have become extinct or surviving in endangered state due to pollution. Excessive use of pesticides has immense effect on depletion of biodiversity. Industrial pollution is a big threat for coral reef.
Hunting and poaching: Until the middle of the last century, wild animals were hunted for fun. The big cats became endangered due to indiscriminate hunting, Poachers kill animals for tusks, horns, skins etc. Some tribes celebrate hunting competition. These practices cut down the population of different animals. Several species jaguar and ocelot have been jeopardized by the demand for their fur.
Excessive use: Ayurvedic medicine producers collect huge quantity of medicinal herbs or plant parts from forest. As a result, the number of several medicinally important plants have reduced significantly. For Example, coptis teeta-an endangered plant is used to regulate blood pressure.
Natural calamity: Forest fire is the deadliest of the natural calamities, which reduce biodiversity very fast. Volcanic eruption, flood, tsunami, earthquakes etc. are few other natural calamities, which have reduced biodiversity at different times. For example Cave beers are extinct due to this.
Invasion of other species: Invasion of foreign species like water hyacinth, tilapia fish, hybrid catfish, etc. greatly hamper the ecological structure of an area. The american cockroach Periplaneta americana harms the local cockroach of India, Le, Blatta orientalis.

4. Explain the problems of Sundarban.

Similar question, You have identified three environmental problems while on a research in Sundarbans-

(a) Disbalance in predator number, (b) Destruction of mangrove plants due to urbanization, (c) Submergence of islands due to rising sea level. Analyse what impact they might exert on biodiversity.

Part question, If the water level in sea increases enormously due to global warming, what problems the humans and biodiversity of Sunderban may face?

Part question, Construct a concept map to show how the increase in human habitat is influencing the ecosystem of Sundarban.

Ans. Problems of Sundarban

In recent days Sundarban is facing many environmental problems. These are mentioned below.

Loss of mangrove forest due to urbanisation: Population pressure has initiated urbanisation. Due to this, many areas along the periphery of Sundarban are deforested.
Agricultural problem: Due to soil erosion and siltation, the depth of rivers becomes shallow. During high tide saline water spills over, floods the agricultural fields to make the soil salty and infertile.
Scarcity of fresh water: The estuarine water is salty. Frequent flood makes the inland water bodies like ponds, wells saline. Therefore, sweet water is becoming scarce in Sundarban area.
Destruction of natural habitat: Deforestation is reducing the natural habitats of large to small animals. As a result, the biodiversity of Sundarban is gradually getting destroyed.
Pollution: The most provocative problem for Sundarban is the increasing pollution. All rivers are disposing gallons of pollutants in the water. Several pollutants are percolating in the soil of Sundarban area making the soil infertile and toxic. The oil and grease, spilling from fishing and tourist vessels are polluting the aquatic environment of this area. This pollution is affecting the propagation of fish, prawn and other aquatic animals.
Imbalance in prey-predator ratio: Due to over population and pollution, number of many animal species has declined. This has resulted into imbalance in prey-predator ratio. Scarcity of natural food compels tigers to enter into human locality in search of food.
Rise in water level: Due to global warming, the glaciers of polar region are melting. This results into increase in sea water level. As a result, the delta of Sundarban is going under seawater.

5. Mention the roles of biodiversity in the following two aspects in the progress of human civilization-

(a) Production of food, (b) Manufacturing of Medicine.

Ans. Production of food

We all are depends on nature for food. Nature can give us a wide range of various organisms that meet the need of food. Different food items provide different essential nutrients like-Vitamin, mineral along with energy. Other than that a wide range of animal protein are also acquired from poultry and fishery. All these animals and plants are the gift of biodiversity of nature. 1

Manufacturing of medicine

In early decade. We mainly depended on plants for medicine. Variety of plant species are provided by biodiversity, mainly used for medicinal purposes. Not only plants, many fungi and body parts of animals are also used as medicine. For e.g. we get quinine from cinchona plant; a vital drug for malaria reserpine from the roots of rouwolfia; maintain blood pressure level to normal, daturine from datura prevent hyperventilation etc. Along with that, holy basil, margosa plants are also exerts their medical values. Fungi like Punicillium notatum is essential for producing penicillin, an antibiotic that fight against a wide range of bacteria. So biodiversity help to progress overall human welfare and civilization.

Short Answer Type Questions

1. What is meant by species?

Ans. Species is a group of closely related, characteristically similar and naturally interbreeding organisms, which are capable of producing fertile offsprings to create a population. For example, there are seven species of honey bee in our planet.

2. What is biodiversity?

Ans. The intraspecific, interspecific or ecological variation seen among the different living organisms, inhabiting any terrestrial or aquatic environment, is called biodiversity. It is a measure of the variety of organisms present in different ecosystems. Example-Coral reef biodiversity.

3. What are endemic species?

Ans. The animal or plant species, which remain naturally confined to a particular geographical area, are called endemic species. Example Asiatic lion is endemic to Gir forest, muga silk moth is endemic to Assam.

4. Now do you classify biodiversity on the basis of their interrelations?

Ans. On the basis of interrelation, biodiversity is classified into 3 different types-[1] genetic diversity, [2] species diversity & [3] ecological diversity.

5. Name any two organisations, which work for developing awareness on the importance of rtance of biodiversity.

Ans. Several international organisations work for developing awareness on the importance of biodiversity. Two of these are-[1] WWF (World Wide Fund for Nature) and [2] IUCN (International Union for Conservation of Nature and Natural Resources).

6. What is genetic diversity?

Ans. Several chromosomal and genetic differences occur within a population. These create many structural and behavioural variations within the members of the same species. This is called genetic diversity.

7. What is species diversity?

Ans. Within a biotic community of a particular area, several species interact with each other. The structural and behavioral variations of these organisms and the differences in relative abundance of all these species in a biotic community are known as species diversity.

8. What is ecological diversity?

Ans. Different interacting ecosystems within a vast geographic area possess a wide variety of species. Such diversity among the organisms in a very large area is known as ecological diversity.

9. What is meant by biodiversity hotspot?

Ans. There are some regions on the earth which comprise several endangered and rare endemic species, are known as biodiversity hotspot. Western Ghats and Eastern Himalayas are two important biodiversity hotspots in India.

10. How many types we classify the ecological diversity and what are they?

Ans. Ecological diversity can be classified into three types. They are-[1] Alpha diversity, [2] Beta diversity and [3] Gamma diversity.

11. Give two examples of animal biodiversity endangered by the pollution of the river Ganga.

Ans. Two examples of animal biodiversity endangered by the pollution of river Ganga aregangetic dolphin and gharial.

12. Which parts are included in Eastern Himalayas and Sundaland biodiversity hotspots?

Ans. The forests of Sikkim, North Bengal and Arunachal Pradesh are included in the Eastern Himalayas biodiversity hotspot. Sumatra, Borneo and Nicobar islands are included in Sundaland biodiversity hotspot.

13. Why is the Eastern Himalayas called a biodiversity hotspot ?

Ans. In Eastern Himalayas, there are several endemic animal and plant species. Here, about 5800 species of plants and 2000 species of animals are found, all of which are endemic. Therefore, Eastern Himalayas is treated as a biodiversity hotspot.

14. Name the biodiversity hotspots in India.

Ans. In India, there are 4 biodiversity hotspots. These include [1] Eastern Himalayas, [2] Western Ghats and Sri Lanka, [3] Indo-Burma and [4] Sundaland.

15. Why is Western Ghats and Sri Lanka treated as biodiversity hotspots?

Ans. In Western Ghats and Sri Lanka, about 5000 different vascular plant species are found, out of which 1700 are endemic. Moreover, around 985 animal species are found here, out of which 360 are endemic species. Due to this richness of endemic species, Western Ghats and Sri Lanka are treated as biodiversity hotspots.

16. Write the location of Sundaland hotspot and one important species of its biodiversity.

Ans. One of the most important biodiversity hotspot Sundaland is located in Southestern Asia, compraises of the landmass of Malay, Java, Sumatra, Peninsula, Bali, Borneo and Andaman and Nicobar islands. The important species of Sundaland is-Sundari plant (plant) or Orangutan (animal),

17. Which Indian states come under Western Ghats and Sri Lanka hotspot?

Ans. The Indian states those come under Western Ghats and Sri Lanka hotspot are Gujarat, Maharashtra, Karnataka and Kerala.

18. Which are the two conditions imposed by the ‘conservation International’ to declare an area as biodiversity hotspot?

Or, Which conditions do you consider to declare one area out of two as biodiversity hotspot?

Ans. The two conditions imposed by the ‘conservation international’ to declare an area as biodiversity hotspot are as follows-[1] The area must have at least 1500 endemic vascular plant species. [2] About 70% of biodiversity of that area should have already been extinct.

19. Discuss the role of biodiversity in maintaining balance of eco-system of a river.

Ans. Role of biodiversity in maintaining balance of eco-system of a river are-[1] Biodiversity decreases the inter and intra-specific competition of aquatic organisms for food and habitat. [2] Depletion of certain aquatic organisms due to water pollution, hampers the river ecosystem. This can be restored by biodiversity. [3] Extensive biodiversity provide certain options to nature like killifish, which can withstand with extreme environmental change (water pollution).

20. Which states come under Indo-Burma hotspot?

Ans. A number of states come under Indo-Burma hotspot. These are-Manipur, Mizoram, Tripura, Meghalaya, Arunachal Pradesh and southern Assam.

21. Mention the location of Sundarban.

Ans. Sundarban is located at the southern part of South 24 parganas of West Bengal and southern portion of Khulna district of Bangladesh. Its geographical position is 21°32′ to 21°55′ northern latitude and 88°42′ to 89°04 eastern longitude. The total surface area of sundarban is 9630 sq km.

22. Which types of plants are called halophytes or mangrove plants?

Ans. The plants, which grow in the saline, silty and muddy soil along the bank of estuaries and sea shore are called halophytes or mangrove plants. Example-Sundari (Heritiera), Garan (Ceriops) etc.

23. Mention the importances of mangrove forest in Sundarban.

Ans. The importances of mangrove forest in Sundarban are as follows-[1] Root system of mangrove trees holds the soil to prevent erosion of soil and breaking of coastline. [2] This forest protects coastal area against storm and supplies wood, honey etc. to the residents of this area.

24. Name few endangered plants and animals of Sundarban.

Ans. The endangered plants of Sundarban are Sundari (Heritiera), Geon (Excoecaria) etc. Among animal species, the endangered ones are Royal Bengal tiger, fishing cat etc.

25. What are the reasons of destruction of mangrove forest of Sundarban?

Ans. T reasons of destruction of mangrove forest are-[1] cutting of mangrove tree for place of human habitat. [2] Natural calamities like cyclone destroy mangrove forest. [3] Pollution causes destruction of mangrove plants. [4] Mangrove plants are cut for prawn culture.

26. Write down few process of protecting biodiversity.

Ans. Few processes of protecting biodiversity are[1] Identifying the endangered species and to be neccessary steps for taken their conservation. [2] Plantation and prevention of local plant destruction. [3] Increasing awareness among people and sustainable use of forest products.

27. What is biodiversity treaty?

Ans. In the Earth summit of 1992 in Rio de Janeiro, 150 Brazil, top level representatives from countries unanimously signed a treaty for the conservation of biological diversities (CBD). This is known as biodiversity treaty.

28. Mention the important features of biodiversity treaty.

Ans. The important features of biodiversity treaty are as follows-[1] Conservation of biodiversity. [2] Sustainable utilisation of the products collected from biodiversity. [3] Arrangement of impartial utilisation of genetic resources from biodiversity.

29. Give four examples of damages of biodiversity as a result of global warming.

Ans. Due to global warming four examples of damage of biodiversity are-[1] Destruction of Australian coral reef leads to loss of marine biodiversity. [2] In present decade, the overall temperature of earth rises about 1-2°C, that inturn melt the ice in polar regions. Because of these; animals of polar regions like penguine, polar bear, seal are losing their habitat and thereby their number decreases rapidly. [3] Extinction of certain species of amphibia, fish, snails, shells, migratory birds are the results of global warming. [4] Destruction of mangrove forest is also a result of global warming, due to rise in sea level.

30. Cites two examples of foreign species causing harm to local species.

Ans. Two examples of foreign species causing harm to local species are-[1] The american cockroach Periplaneta americana harms the local cockroach of India Blatta orientalis. [2] The plant water hyacinth coming form Brazil inhibit other aquatic plants.

31. Give one example of exotic species causing damage of local biodiversities in each of terrestrial and aquatic ecosystem?

Ans. In aquatic ecosystem, the exotic species that damage the local biodiversity is-water hyacinth. In terrestrial ecosystem, the exotic species that damage the local biodiversity is-american cockroach.

32. ‘Poaching is one of the fundamental causes of endangeredness of animal diversity in India’-Assess four causes for which animals are poached in India.

Ans. Four causes of poaching are [1] Some animals are mainly killed for their skins and bones, e.g. Eleplents are killed for ivory and tigers are killed for their bones and skins. [2] Some animals like deer, pig, bull are poached for meet the needs of meat. [3] Body parts of some animals are also used for medicinal purpose and for home decor. [4] Illegally traded items fetch lucrative price, that encourages poacher to look out for more money.

33. Pollution is the reason of depletion of biodiversity Justify.

Ans. [1] Pollution increase the average temperature causing global warming. Due to global warming glaciers melt causing problems for polar animals like polar beer, penguin etc. [2] Increasing temperture increases water level of sea causing destruction of mangrove forest of Sundarban. [3] Pollutin causing destruction of coral reef. [4] Pollution harm the health of many animals.

34. Give two example of biodiversity depletion due to increase in human population.

Ans. [1] Deforestation-Plants are cut for habitat and other facilities of human like in Indonesia forests are cut for increasing oil production. [2] Excessive use-Many plants and animals are used excessively for human welfare or entertainment, deplets biodiversity. Passenger pigeon become extinct due to this.

Very Short Answer Type Questions

Multiple Choice Questions & Answers [MCQ]

1. The term ‘biodiversity’ was coined by-

A. Zimmermann

B. W G Rosen

C. Charles Darwin

D. Lamarck

Ans. B

2. The diversity of various communities of organisms inhabiting a vast geographical area is known as-

A. Genetic diversity

B. α diversity

C. β diversity

D. γ diversity

Ans. D

3. Total number of biodiversity hotspots on Earth is-

A. 14

B. 24

C. 34

D. 44

Ans. C

4. The concept of ‘hotspot’ was given by-

A. David

B. Simpson

C. Mayer

D. Norman Myers

Ans. D

5. The ecological area with very rich biodiversity is called-

A. Blue spot

B. Green spot

C. Cold spot

D. Hotspot

Ans. D

6. Out of 34 biodiversity hotspots worldwide, in India there are-

A. 2

B. 4

C. 8

D. 16

Ans. B

7. The main cause of extinction of biodiversity from equatorial region is-

A. Deforestation

B. Erosion of soil

C. Earthquake

D. Super cyclone

Ans. A

8. The plant species present in India is-

A. 10% of the global plants

B. 11% of the global plants

C. 12% of the global plants

D. 13% of the global plants

Ans. B

9. A biodiversity hotspot in India is-

A. Nilgiri hills

B. Aravalli hills

C. Western Ghats

D. Eastern Ghats

Ans. C

10. The mangoes available in Malda have different tastes, flavours, fibrous content, colours and sugar content. This is due to-

A. Hybridisation

B. Species diversity

C. Induced mutation

D. Genetic diversity

Ans. D

11. The medicinal plant used to reduce high blood pressure is-

A. Sarpagandha (Rauvolfia)

B. Cinchona

C. Guava (Psidium)

D. Kalmegh (Andrographis)

Ans. A

12. In a hotspot, the minimum number of endemic vascular plants that should be present, is-

A. 1500

B. 1600

C. 1700

D. 1800

Ans. A

13. In Sundaland, the number of vascular plants present, is about-

A. 25000

B. 30000

C. 35000

D. 40000

Ans. A

14. The Indian biodiversity hotspot, which includes Sikkim, Assam, Arunachal Pradeshand North Bengal is-

A. Indo-Burma region

B. Eastern Himalayan region

C. Western Ghats region

D. Sundaland

Ans. B

15. Water hyacinth was introduced in India from-

A. Australia

B. South America

C. Japan

D. Nepal

Ans. B

16. The percentage of endemic plant species in India, is about-

A. 11%

B. 22% .

C. 33%

D. 44%

Ans. B

17. The main cause of declining number of tigers in Sundarban is-

A. Expansion of residential area

B. Poaching

C. Forest management

D. All of these

Ans. C

18. International day for biological diversity’ is celebrated on-

A. 5th June

B. 22nd March

C. 29th November

D. 22nd May

Ans. C

19 The species that is not abundant in nature but plays a very important role in maintaining ecological balance is called-

A. Keystone species

B. Endangered species

C. Rare species

D. Vulnerable species

Ans. D

20. Species diversity occurs due to-

A. Genetic variation

B. Ecological biodiversity

C. Animal diversity

D. Plant diversity

Ans. D

21. Mangrove forest is seen in-

A. Dry desert area

B. Hilly area

C. Plateau

D. Salty wetland

Ans. A

22. The forest area in India is about-

A. 19 %

B. 91 %

C. 52 %

D. 23 %

Ans. A

23. In India, the highest number of reptiles are found in-

A. Himalayas

B. Western Ghats

C. Deccan plateau

D. Sundarban

Ans. D

24. The exogenous plants that have created great ecological problem are-

A. Parthenium and water hyacinth

B. Bryophyllum and Begonia

C. Berry and banana

D. Shame plant and Calotropis

Ans. D

25. Two endangered animals of India are-

A. Indian tiger and musk deer

B. Indian ass and wild boar

C. Cat and mongoose

D. Wild cat and wild dog

Ans. B

26. Endangered plants of India are—

A. Sundari, pitcher plant and sandal

B. Mango, berry and jackfruit

C. Paddy, wheat and millet

D. Silk cotton, arjun and tamarind

Ans. A

27. Synonym of ecological diversity is-

A. Genetic diversity

B. Species diversity

C. Habitat diversity

D. Animal diversity

Ans. A

28. The largest mangrove forest is situated in-

A. Jalpaiguri

B. Midnapore

C. Sundarban

D. Purulia

Ans. A

29. Which of the following is not a hotspot?

A. Indo Burma

B. Western Ghat

C. Sundarban

D. Eastern Himalaya

Ans. C

30. Sundarban is –

A. National park

B. Hotspot

C. Biosphere reserve

D. Sanctuary

Ans. B

31. The keystone species of Sundarban is-

A. Mangrove

B. Royal Bengal tiger

C. Lion

D. Fish

Ans. B

32. Which of the following plant destroy the biodiversity of an ecosystem –

A. Mango

B. Pea

C. Eucalyptus

D. Arjun plant

Ans. C

Answer in a single word or sentence

1. How do you denote the combination of ecosystem and biodiversity?

Ans. The combination of ecosystem and biodiversity is called ecological diversity.

2. What is the basis of a healthy and active ecosystem?

Ans. A rich biodiversity is the basis of healthy and active ecosystem.

3. What is the species diversity in two different habitats within a same geographical area known as?

Ans. Beta (β) diversity

4. How do you denote the genetic variations among the members of the same species?

Ans. Genetic diversity

5. How do you treat the abundance of relatively different species in a specific area?

Ans. Species diversity

6. Which type of diversity is called turnover diversity?

Ans. Beta (β) diversity

7. Which type of diversity indicates the abundance of different species in a specific area?

Ans. Alpha (α) diversity

8. How do you denote the diversity of various species inhabiting a vast geographic area?

Ans. Gamma (γ) diversity

9. Name a mangrove plant.

Ans. Sundari (Heritiera littoralis)

10. What is flora?

Ans. Flora is the collection of all species of plants inhabiting an area or a geological time.

11. What is vegetation?

Ans. Vegetation is the generalised idea on the distribution, number, nature etc. of all plants inhabiting a specific area.

12. How do you denote the places, which are rich in rare and endemic biodiversity?

Ans. The places, which are rich in rare and endemic biodiversity, are called hotspots.

13. In which biodiversity hotspot in India is leaf deer seen?

Ans. Eastern Himalayas

14. Write the full form of BMC.

Ans. Biodiversity Management Committee

15. What is the total geographical area of India?

Ans. 32,87,263 km²

16. According to FSI-2011, what percentage of Indian landmass is covered by forest?

Ans. According to FSI-2011, 21.05% of Indian landmass is covered by forest.

17. In which portion of the earth does the richest biodiversity occur?

Ans. The richest biodiversity occurs in the tropical rain forest region of the earth.

18. Name a keystone species in West Bengal.

Ans. Royal Bengal tiger

19. What percentage of species of the world is confined to the megadiversity countries.

Ans. 70%

20. Which day is a celebrate as world environment day?

Ans. 5th June

21. Which day is Celebrated as world Conservation day?

Ans. 3rd December

22. When and where the earth summit took place?

Ans. 1992 in Rio de Janeiro

23. What is the full form of CBD.

Ans. Convention of biological diversity

24. How many hotspots are there in India?

Ans. Four

25. Write down the names of two hotspots in India.

Ans. Eastern Himalaya and Western Ghat

26. Write down the name of a plant of Eastern Himalaya.

Ans. Pitcher plant (Nepenthes khasiana)

27. Which day is celebrated as world biodiversity day.

Ans. 22 May

28. Write down the name of a mammal of Eastern Himalaya.

Ans. Red panda (Ailurus fulgens)

29. Which forest of India is declared as world heritage site by UNESCO.

Ans. Sundarban

30. Sundarban is famous for conservation of which animal?

Ans. Royal Bengal tiger

31. What percentage of forest area is present in India according to 2011 report of FSI.

Ans. 21.05%

32. Write the name of the cause of the latest concern regarding the environment at Sundarbans.

Ans. Loss of mangrove and scarcity of drinking water.

Fill in the blanks

1. Among all living organisms on the earth, about …………. % is present only in 17 countries.

Ans. 70

2. The source of quinine is ………. plant.

Ans. Cinchona

3. ………. is used as a medicine to treat malaria.

Ans. Quinine

4. A beneficial fungus is ……….

Ans. Penicillium

5. Reserpine, the medicine for high blood pressure is extracted from roots of ………… plant.

Ans. Sarpagandha

6. ……… is a medicinal plant, extract of which can be used as immunostimulant.

Ans. Kalmegh

7. The green plants are the ……….. of ecosystem.

Ans. Producers

8. Wood from ……….. plant is generally used for making furniture.

Ans. Teak

9. The pulp prepared for paper industry contains ……….. fibres of the plant.

Ans. Cellulose

10. ……….. plant is used for paper production.

Ans. Bamboo

11. The …………. secreted from babool, shirish etc. plants is used to prepare glue.

Ans. Gum

12. Resin of pine is used to prepare ………… oil.

Ans. Turpentine

13. ……….. is a type of resin, used to add flavour in food.

Ans. Asafoetida

14. Bee wax is used in preparing ………..

Ans. Cosmetics

15. Bombyx mori produces ……….. silk.

Ans. Mulberry

16. Angora wool is collected from …………. fur.

Ans. Rabbit

17. The biodiversity hotspot in which the Nicobar Islands are included is ………..

Ans. Sundaland

18. The Eastern Himalayas hotspot is called the cradle of ………..

Ans. Speciation

19. In Eastern Himalayas hotspot, about ………. endemic flowering plant species are found.

Ans. 2000

20. In the Indo-Burma hotspot, about ……… species of mammals are found.

Ans. 430

21. The hotspot of south India is …………..

Ans. Western ghat

22. ………… is a keystone species.

Ans. Royal Bengal tiger

23. ……….. ray is entering into the earth due to ozone layer depletion.

Ans. UV ray

24. The term hotstop was comed by …………

Ans. Norman Myers

25. The name of one exotic species, that affects the local biodiversity, is …………

Ans. Parthenium

26. ………… is derived from the root of sarpaganda plant which is need as medicine form lowering high blood pressure.

Ans. Reserpine

SUB-TOPIC – 4.2

BIODIVERSITY CONSERVATION

SUMMARY

Biodiversity conservation is important to maintain sustainable life. This conservation is of two types. In-situ and Ex-situ conservation.
Conservation of organisms in their natural habitat is called in-situ conservation. National park, sanctuary, biosphere reserve are the examples of in-situ conservation.
Conservation of endangered species other than their natural habitat is called- ex-situ conservation. zoo, botanical garden etc. are the examples of ex-situ conservation.
Cryopreservation is a special type of ex-situ conservation. By using liquid nitrogen at −196°C temperature, sperm and egg from animals and pollen, seed; etc. from plants are preserved by this process.

Long Answer Type Questions

1. What is biosphere reserve? Mention the structure of a biosphere reserve.

Ans. Biosphere Reserve

To minimise the conflict between development and conservation, UNESCO has introduced a new concept. According to this concept, a large landmass or coastal area is demarcated into different zones based on their functional importance. Here, conservation of endangered species, ecotourism, educational excursion and human inhabitancy can be carried out, side by side without causing any harm to others. This type of area is called biosphere reserve. Example-Sundarban in West Bengal and Nilgiri hills in Tamilnadu are two biosphere reserves.

Structure of a biosphere reserve

[a] A biosphere reserve has a central core zone for conservation of wildlife. In this zone, any type of human intervention is completely prohibited. Here, the animals thrive and reproduce freely. [2] Surrounding, the core area, there is a buffer zone, where ecotourism or educational excursion and research works may be conducted. [3] The third zone is the transition zone situated beyond the buffer zone, where human inhabitancy, storage of logs and other harvested matters and forest security activities are allowed.

2. Mention the importance of conservation of biodiversity.

Ans. Importance of conservation of biodiversity

The importance of conservation of biodiversity are mentioned below.

Storage of food: Biodiversity is the store house of food for all the living organisms on the earth. To keep the store intact we must conserve the biodiversity.
Source of energy: Green plants absorb CO₂ from the environment and H₂O to synthesise carbohydrate as food. In this reaction solar energy is trapped in the carbohydrate as chemical energy. Through food chain, this energy is distributed among all the members of an ecosystem. Therefore, conservation of biodiversity is essential for survival of the living world.
Store of gene pool: Biodiversity is the store of gene pool. This genetic diversity is essential for adaptation and evolution of new species.
Source of medicine: Thousands of plants are there with immense medicinal importance. Scientists have found innumerable plants species, which are directly or indirectly involved in the production of medicines.
Source of raw material for industries: We get various raw materials for different industries from plants and animals. Therefore, biodiversity is important for industries also.
Ecological importance: In an ecosystem, different living organisms remain interconnected through food web. The organisms include producers, consumers and decomposers. If existence of any of these levels is in danger the whole ecosystem will break. Therefore, conservation of biodiversity is important to maintain ecological balance.

3. Explain the methods of conservation of biodiversity.

Ans. Methods of conservation of biodiversity

Conservation of biodiversity is done in two ways-[1] In-situ conservation and [2] Ex-situ conservation. These are explained below.

In-situ conservation: Protecting animals and plant within their natural habitat to facilitate their natural propagation by reducing undesirable human intervention and indiscriminate hunting, poaching and chopping of trees is known as in-situ conservation. This type of conservation is practiced in national parks, sanctuaries, protected forests and biosphere reserves. Characteristic features of these sites are mentioned below.
1. National park: The largest of the forest areas, those remain under direct control of the national government where poaching, hunting, felling of trees or fishing is completely prohibited to ensure safe living and propagation of some endangered and rare organisms are known as national park. Ecotourism is allowed up to a certain limit with due permission from the department of forestry. According to the national report 2013, 102 forests are demarcated as national park. Example-Gonumara National Park (West Bengal), Kanha National park (Madhya Pradesh).
2. Sanctuary: A vast forest area, under the control of state government, in which human intervention for poaching, hunting, felling of trees or fishing is completely prohibited to ensure safe living and propagation of some endangered and rare organisms, is known as sanctuary. Controlled human intervention in a sanctuary may be allowed for the purpose of protective survey, census and research works only. According to the national report 2013,there are 515 sanctuaries in India. Example-Chapramari Wildlife Sanctuary (West Bengal), Palamau Wildlife Sanctuary (Jharkhand).
3. Reserve forest According to the Indian Forest Act 1917, there are few forests under management of the forest department under state government in which entry of general public is completely restricted, cutting of trees, hunting, grazing of cattle and scientific researches are allowed to enter with due permission from the state forest department are known as reserve forest. Example-Sholayar Reserve Forest of Kerala, Hanamsagar Reserve Forest of Karnataka.
4. Biosphere reserve: To minimise the conflict benveen development and conservation, UNESCO introduced a new concept by which a large landmass or coastal area is demarcated into different zones based on their functional importance and in which conservation of endangered species, ecotourism, educational excursion and human inhabitancy is carried out side by side without causing any harm to others. This type of area is called biosphere reserve. Example-Sundarban in West Bengal and Nilgiri hills in Tamilnadu are two biosphere reserves.
Ex-situ conservation: To provide extra protection and close monitoring, some animals and plants are protected in artificially built areas away from their natural habitar. This type of conservation is known as ex-situ conservation. This type of conservation is done in zoo-gardens, botanical gardens, cryopreservation centres etc.
1. Zoo: Various terrestrial and aquatic animals are protected in zoos under close surveillance of zoologists and veterinary specialists. Example-Alipore Zoological garden.
2. Botanical gardens: Several rare, endangered and vulnerable plant species are reared in botanical gardens under the care of botanists. Example-Shibpur Botanical garden.
3. Cryopreservation centres. Cryopreservation is a laboratory technique by which tissues, embryos, body parts etc. of plants and animals are preserved in liquefied nitrogen at a temperature of -196°C. Example-Botanical Survey of India, Shibpur.

Short Answer Type Questions

1. Mention two objectives of conservation.

Ans. Two objectives of conservation are as follows-[1] To render the rare and endangered species of plants and animals better environment to reproduce at rapid rate and better survival on the earth. [2] To ensure of controlled and sustainable utilisation of natural resources.

2. What do you mean by conservation of biodiversity?

Ans. Conservation of biodiversity is the protection and scientific management of the biosphere by human beings. This process provides maximum benefit for the present generation and the recent ecosystem. It also means that the biosphere develops its potential to meet the needs of the future generations and the future ecosystem as well.

3. What is in-situ conservation?

Ans. Protecting animals and plants within their natural habitat to facilitate their natural propagation is called in-situ conservation. In-situ conservation reduces undesirable human intervention and indiscriminate hunting, poaching of animals and chopping of trees. Example-Conservation of tiger and rhino in national parks or biosphere reserves.

4. Mention the advantages of in-situ conservation?

Ans. The advantages of in-situ conservation are as follows-[1] Conservation in natural habitat is less expensive. [2] In this process, the success rate of reproduction is much higher than in captivity.

5. Mention the disadvantages of in-situ conservation.

Ans. The disadvantages of in-situ conservation are as follows-[1] It needs a large forest area or water body. [2] The diseased animals cannot be sorted out for treatment, therefore, certain diseases like anthrax, may become epidemic.

6. Mention the important sites for in-situ sites for in-si conservation.

Ans. There are a few natural sites, designated for in-situ conservation. These are-national parks, biosphere reserves, sanctuaries and protected forests.

7. What are national parks?

Ans. The largest of the forest areas, those remain under direct control of the government of India, where poaching, hunting, felling of trees or fishing is completely prohibited to ensure safe living and propagation of some endangered and rare organisms, but ecotourism is allowed up to a certain limit with due permission from the department of forestry, are known as national park. Example-Gorumara National Park, (West Bengal), Kanha National Park (Madhya Pradesh).

8. Give two examples of ex-situ conservation.

Ans. The two examples of ex-situ conservation are [1] Zoo (Alipur Zoo) and [2] Botanical garden (Acharya Jagadish Chandra Bose Indian Botanic Garden).

9. Give examples of a national park and a biosphere reserve situated in West Bengal.

Ans. An example of the national park, situated in West Bengal is jaldapara national park and a biosphere reserve is sundarban biosphere reserve.

10. Mention the characteristic features of a national park.

Ans. The characteristic features of a national park are as follows-[1] National park is a vast area, controlled by the central government for the conservation of rare and endangered animals and plants. [2] In a national park, hunting, fishing and felling of trees are completely prohibited.

11. Name some animals, which are protected in Corbett National Park in Uttarakhand?

Ans. A number of rare and endangered animals are protected in Corbett National Park in Uttarakhand. These include tiger, elephant, gaur, Indian grey mongoose, pangolin etc.

12. Mention the objectives of establishing national park.

Ans. There are few objectives of establishing national parks. These are-[1] Protection of rare and endangered animals. [2] Providing adequate food and breeding ground for the animals. [3] Maintaining a perfectly balanced natural ecosystem.

13. What is a sanctuary?

Ans. A vast forest area, under the control of state government, in which human intervention, poaching, hunting, felling of trees or fishing is completely prohibited to ensure safe living and propagation of some endangered and rare organisms, is known as sanctuary. Controlled human intervention in a sanctuary may be allowed for the purpose of protective survey, census and research works only. ExampleChapramari (West Bengal), Palamau (Jharkhand).

14. Mention two characteristic features of a sanctuary.

Ans. Two characteristic features of a sanctuary are as follows-[1] The management of a sanctuary remains under the state government. [2] Human intervention in a sanctuary is completely prohibited. However, entrance is allowed for scientists only after prior permission from the concerned authority.

15. Mention two importances of sanctuary.

Ans. Two sanctuary areimportances of [1] Protection of wildlife against hunters and poachers. [2] Conservation of endangered and rare species in their natural habitat.

16. Tabulate any of the four activities which are prohibited in a sanctuary following the provisions of Wildlife Act.

Ans. The four activities, that prohibited in sanctuary are-[1] Human intervention in the sanctuary is strictly prohibited. [2] Any human activity which disturbs the wild animals is prohibited. [3] Poaching, hunting, fishing is strictly prohibited. [4] Felling of trees is completely prohibited.

17. What are reserve forests?

Ans. According to the Indian Forest Act, 1917, there are several forests under management of the state government in which entry of public is completely restricted, only the scientists are allowed to enter with due permission from the state forest department. Those forests are known as reserve forests. Example-Sholayar Reserve Forest of Kerala, Hanamsagar Reserve Forest of Karnataka.

18. Mention two significances of biosphere reserve.

Ans. Two significance of biosphere reserve are as follows-[1] The species diversity and genetic diversity are preserved in biosphere reserve. [2] In a biosphere reserve, the qualitative development of human and nature interaction can be achieved.

19. Mention the characteristic features of reserve forest.

Ans. The characteristic features of reserve forest are as follows-[1] The management of reserve forest is completely a state government affair. [2] In this forest, felling of trees, hunting of animals is not allowed without the legal permission.

20. What is ex-situ conservation?

Ans. To provide extra protection and close monitoring, some animals and plants are protected in artificially built areas away from their natural habitat. This is known as ex-situ conservation. Example- Conservation of plants in botanical gardens or zoos.

21. Mention the advantages of ex-situ conservation.

Ans. The advantages of ex-situ conservation are as follows-[1] By this mode of conservation, the organisms are monitored closely, therefore, they can be medically attended as soon as any disease affects them. [2] Due to lack of competition, the organisms get adequate food and the percentage of neonatal death can be reduced greatly. [3] Cryopreserved germ cells or spores may be used to produce these organisms in future if their count goes down very fast.

22. What are the disadvantages of ex-situ conservation?

Ans. The disadvantages of ex-situ conservation are as follows-[1] Many animals and plants do not reproduce in captivity. Several plants become weak in absence of ambient temperature, humidity and soil composition. [2] Ex-situ conservation is expensive and it needs a good infrastructure.

23. Mention the common places of ex-situ mmon places of exconservation.

Ans. Ex-situ conservation is done in many places. These are-[1] Gene bank, [2] Zoo, [3] Aquarium, [4] Arboretum, and [5] Botanical garden etc.

24. Mention two roles of a zoological garden as a place of ex-situ conservation.

Ans. Role of a zoological garden as a place of ex-situ conservation are as follows-[1] In a zoo, terrestrial and aquatic animals from different places are kept in suitable artificial habitat to increase their population size [2] In this place possible infrastructural and veterinary supports are provided to the animals help them to reproduce in captivity. If population size increases, few of them are set free in their natural habitat.

25. Give two examples of zoological gardens used for ex-situ conservation.

Ans. Two examples of zoological gardens used for ex-situ conservation are as follows-[1] Alipur Zoological garden in West Bengal, acts as an ex-situ conservation centre for Royal Bengal tiger, Asiatic lion, elephant, crocodiles. [2] The Indira Gandhi Zoological Park, at Visakhapatnam, Andhra Pradesh, protects sloth bear, wild dog, puma, jaguar as ex-situ conservation.

26. Mention two characteristic features of botanical garden as a site for ex-situ conservation.

Ans. The characteristic features of botanical garden as a site for ex-situ conservation are follows[1] Various rare and endangered plants and medicinal herbs are nurtured in botanical gardens and for ex-situ conservation. [2] The rare end angered plants are allowed to propagate under scientific surveillance to increase their number.

27. I What is meant by cryopreservation?

Ans. Cryopreservation is a laboratory technique by which any tissue, embryo, body parts of animals and plants are preserved in liquefied nitrogen at a temperature of -196°C.

28. Mention the characteristic features of cryopreservation. Give an example of cryopreservation centre.

Ans. Features of cryopreservation: The characteristic features of cryopreservation are as follows-[1] In this type of preservation, liquefied nitrogen is used to maintain at a temperature of -196°C. [2] In this process, pollen grains, seeds, gametes etc. are preserved.

Example of cryopreservation centre: An example of a cryopreservation centre is Botanical survey of India, Shibpur, Howrah.

29. Give examples of two botanical gardens in India used for ex-situ conservation.

Ans. There are several botanical gardens in India Two botanical gardens in India used for ex-situ conservation are-[1] Acharya Jagadish Chandra Bose Indian botanic garden at Shibpur, Howrah and [2] Jawaharlal Nehru Tropical botanical garden and research institute, Trivandrum, Kerala.

30. What is arboretum?

Ans. Arboretum is a method of ex-situ conservation. Here, rare and endangered plants are studied, reared and propagated under scientific surveillance.

31. What is meant by sacred forest?

Ans. Out of a religious belief, native tribes of some regions protect a section of a forest along with its animals and plants and treat this block of forest as a sacred place. This section of forest is called sacred forest. Example-In Thar desert of Rajasthan, people of Bishnoi tribes maintain a sacred forest for generations.

32. What are sacred lakes?

Ans. Out of religious belief, tribes of few regions of India protect certain water bodies along with all their inhabitants. These water bodies, are called sacred lakes. Example-Khecheopalri lake of Sikkim is one of such sacred lakes.

Very Short Answer Type Questions

Multiple Choice Questions & Answers [MCQ]

1. An example of ex-situ conservation is-

A. National park

B. Reserve forest

C. Seed bank

D. Sanctuary

Ans. C

2. An example of conservation in natural environment is-

A. National park

B. Zoo

C. Arboretum

D. Seed bank

Ans. A

3. The management of national parks in India is controlled by-

A. Central government

B. State government

C. Local institutions

D. United Nations

Ans. A

4. The central region of a biosphere reserve is known as-

A. Reserve area

B. Core area

C. Buffer area

D. Transition area

Ans. B

5. The division of IUCN, under which wildlife sanctuary is included, is-

A. I

B. II

C. III

D. IV

Ans. D

6. Simlipal and Manas are-

A. Biosphere reserves

B. Sanctuaries

C. National parks

D. Biodiversity hotspots

Ans. A

7. Which one of the following is not included under in-situ conservation?

A. Zoo

B. National park

C. Biosphere reserve

D. Sanctuary

Ans. A

8. Kaziranga National Park is specially famous for the conservation of-

A. Deer

B. Elephant

C. One-horned Rhinoceros

D. Lion

Ans. C

9. The number of mega-biodiversity nations is-

A. 10

B. 13

C. 15

D. 17

Ans. D

10. Cashmere wool is prepared from the fur of-

A. Sheep

B. Goat

C. Rabbit

D. Cat

Ans. B

11. The first national park in India is-

A. Bandipur National Park

B. Corbett National Park

C. Kanha National Park

D. Periyar National Park

Ans. B

12. The first week of which month is celebrated as wildlife week?

A. January

B. Apri 1

C. July

D. October

Ans. D

13. Which of the following is the most endangered class?

A. Pisces

B. Reptilia

C. Aves

D. Mammalia

Ans. D

14. The most endangered plants in the world are-

A. Fungi

B. Algae

C. Flowering plants

D. Mosses

Ans. C

15. Sperms, ova, seeds, etc. are stored for prolonged period in liquefied nitrogen at 196°C. This type of preservation process is known as-

A. Bioconservation

B. Cryopreservation

C. Ex-situ conservation

D. In-situ conservation

Ans. B

16. A modern concept of conservation prescribed in the MAB programme of UNESCO is-

A. National park

B. Reserve forest

C. Sanctuary

D. Biosphere reserve

Ans. D

17. The region seen in a biosphere reserve-

A. Core area

B. Buffer area

C. Transition

D. All of these

Ans. D

18. Full form of MAB is-

A. Man and Biology programme

B. Man and Biosphere programme

C. Mammals and Biosphere programme

D. Mammals and Biology programme

Ans. B

19. Conservation of an animal in a national park or wildlife sanctuary is treated as-

A. National park or sanctuary conservation

B. Ex-situ conservation

C. In-situ conservation

D. Keystone conservation

Ans. C

20. The reserved area in West Bengal, where red panda is available, is-

A. Kanha National Park

B. Sajnekhali Wildlife Sanctuary

C. Singalila National Park

D. Jaldapara National Park

Ans. C

21. Poaching of red panda is done due to its-

A. Teeth

B. Bones

C. Meat

D. Furry skin

Ans. D

22. Full form of WWF is-

A. World Wide Fund for Nature

B. World Wide Forum

C. World Wide Forest

D. World Wide Friction

Ans. A

23. An extinct bird of India is-

A. Hornbill

B. Cockatoo

C. Parrot

D. Pink-headed duck

Ans. D

24. Poaching of rhinoceros is done for its-

A. Meat

B. Teeth

C. Claw

D. Horn

Ans. D

25. The state animal of Sikkim is-

A. Fishing cat

B. Red panda

C. Takin

D. Bear

Ans. B

26. Which of the following component is used in cryopreservation-

A. Liquid nitrogen

B. Liquid hydrogen

C. Dry ice

D. Liquid oxygen

Ans. A

27. Gene bank is an example of-

A. Ex-situ Conservation

B. In-situ conservation

C. Hot spot

D. None of the above

Ans. A

28. Gorumara national park is located in-

A. Madhyapradesh

B. Uttar pradesh

C. Kerala

D. West Bengal

Ans. D

29. Which of the following pair is not right-

A. Gir-Gujrat

B. Kanha Uttarpradesh

C. Corbett-uttrakhand

D. Kaziranga-Asssam

Ans. B

30. Simlipal, Sundarban and Manas are-

A. Biosphere reserve

B. Sanctuary

C. National Park

D. Cold spot

Ans. A

31. Nilgiri biosphere reserve is located in-

A. Karnataka

B. Sikkim

C. Orissa

D. Rajasthan

Ans. A

32. According to the census of 2015, the number of Royal Bengal tigers present in Indian Sundarban is-

A. 900

B. 2000

C. 86

D. 500

Ans. C

33. An example of ex-situ conservation is-

A. Sundarban Tiger reserve

B. Corbett National Park

C. Nilgiri Biosphere reserve

D. Cryopreservation

Ans. D

34. Gorumara, Corbett, Kulik, Nandadevi-Choose the correct sequence from the following which is correct for the above forests sequence-

A. Biosphere reserve, Sanctuary, National Park, National Park

B. National Park, National Park, Biosphere reserve, Sanctuary

C. National park, National park, Sanctuary, Biosphere reserve

D. Sanctuary, Biosphere reserve, National park, Sanctuary

Ans. C

35. Identify which of the following is the correct information related to biosphere reserve-

A. Conservation is promoted to local people and other biotic communities along with conservation of ecosystem

B. National Park and sanctuary are not included within biosphere reserve

C. The presence and participation of local people for the conservation of ecosystem are not permissible

D. It’s size is usually smaller than a sanctuary

Ans. A

Answer in a single word or sentence

1. Which is the first biosphere reserve in India?

Ans. Nilgiri Biosphere Reserve

2. At present, how many sanctuaries are there in India?

Ans. 515 sanctuaries

3. In which year was Jaldapara Wildlife Sanctuary considered as national park?

Ans. Jaldapara Wildlife Sanctuary was considered as national park in the year 2012.

4. Name two international organisations, which work for the conservation of biodiversity?

Ans. IUCN and WWF are two international organisations which.

5. Write down the full form of NEERI.

Ans. National Environmental Engineering Research Institute.

6. How many categories are there in the red list of IUCN?

Ans. Nine categories are there in the red list of IUCN.

7. What is the full form of UNDP?

Ans. The full form of UNDP is United Nations Development Programme.

8. What is the full form of FAO?

Ans. Food and Agriculture Organisation.

9. What is the full form of NBPGR?

Ans. National Bureau of Plant Genetic Resources.

10. According to the list of IUCN, under which category are the Indian national parks included?

Ans. According to the list of IUCN, Indian national parks are included under category II.

11. What is the main function of IUCN?

Ans. Conservation of biodiversity all over the globe.

12. According to the list of IUCN, under which category are the reserve forests included?

Ans. The reserve forests are included under category IV or VI.

13. In which year the Forest Conservation Act was implemented in India?

Ans. The Forest Conservation Act was implemented in India in 1980.

14. Where is the Valley of Flowers National Park located?

Ans. The Valley of flowers National Park is located at Uttarakhand.

15. In which country was Dodo bird found before its extinction?

Ans. Dodo bird was found in Mauritius before its extinction.

16. Name a reserve forest in West Bengal.

Ans. Chapramari

17. Name a sanctuary located in Birbhum district of West Bengal.

Ans. Ballavpur Wildlife Sanctuary

18. Name the sanctuary located in North 24 Parganas of West Bengal.

Ans. Bibhutibhushan Wildlife Sanctuary

19. In which state of India is Palamau Wildlife Sanctuary situated?

Ans. Jharkhand

20. What is cryoinjury?

Ans. Sometimes the cellular structure is damaged during ice formation in cryopresorvation, this is called cryoinjury.

21. In which temperature cryopreservation is done.

Ans. –196°c

22. Write down the name of a botanical garden?

Ans. Acharya Jagadish Chandra bose Indian botanical garden or botanic garden.

23. Where does Gir national park is located?

Ans. Gujrat

24. Name one bird sanctuary of West Bengal ?

Ans. Chintamani kar bird sanctuary [Narendrapur]

25. Write down the name of a zoo of West Bengal?

Ans. Zoological garden, Alipore

26. How many biosphere reserves in India come under category V in IUCN schedule?

Ans. In India, 18 Biosphere reserves come under category V in IUCN schedule.

27. In which type of in-situ conservation practice, the diversity, culture and lifestyle of human is preserved anlog with microorganisms, wild animals and wild plants?

Ans. Biosphere reserve

28. Which is the largest national park in India?

Ans. The Desert National Park of Jaisalmer in Rajasthan is the largest (3162 km²) national park in India.

29. Which is the smallest national park in India?

Ans. South Button Island National Park in Andaman is the smallest (5 km²) national park in India.

30. Where is the first marine national park in India situated?

Ans. India’s first marine national park is situated at the Gulf of Kachchh in Jamnagar, Gujarat.

31. How many marine national parks are there in India?

Ans. There are five marine national parks in India.

32. On which day is World Environment Day celebrated?

Ans. 5th June

33. Which day is celebrated every year as the World Conservation Day?

Ans. 3 December

Fill in the blanks

1. Due to rise in sea level, ………… forest area is declining gradually.

Ans. Mangrove

2. In 1997, UNESCO declared …………. as a world heritage site.

Ans. Sundarban

3. Conservation on any organism in a biosphere reserve is an example of ……… conservation.

Ans. In-situ

4. Jaldapara National Park is situated in the state of …………

Ans. West Bengal

5. According to Wildlife Protection Act, ………… , any state government can declare an area as reserve forest.

Ans. 1927

6. A zoological garden is an ………… conservation centre.

Ans. Ex-situ

7. Acharya Jagadish Chandra Bose Indian Botanic Garden is situated in district ………..

Ans. Howrah

8. In the year ………. , the first national park was established in India.

Ans. Brazil

9. The largest national park of India is ………….

Ans. Jim Corbett.

10. Biosphere reserve is a ………… conservation.

Ans. In-situ

11. Lioyd’s botanical garden is situated in ……….. dtrict of west Bengal.

Ans. Darjeeling

12. Full form of MAB is …………

Ans. Men and Biosphere programme

13. Bharatpur bird sanctuary is situated in …………. state.

Ans. Rajasthan

14. A national park of west Bengal is …………

Ans. Jaldapara

15. The ex-situ conservation by keeping sample seeds in liquid nitrogen at a temperature of –196°C is called ………

Ans. Cryopreservation

16. ……….. is a biosphere reserve located in West Bengal.

Ans. Sundarban

State true or false

1. Kangaroo is an endangered species of India.

Ans. False

2. The temperature for cryopreservation is -196°C.

Ans. True

3. The central portion of a biosphere reserve is called the buffer region.

Ans. False

4. Acharya Jagadish Chandra Bose Indian Botanic Garden is situated at Shibpur, Howrah.

Ans. True

5. Sundarban area of West Bengal is a biosphere reserve.

Ans. True

6. Brazil is the country with the richest biodiversity in the world.

Ans. True

7. Chapamari is a national park of West Bengal.

Ans. False

8. National park is a type of In-situ conservation

Ans. True

9. In Manas national park of Assam Royal Bengal tiger is conserved.

Ans. False

10. One-horned rhinoceros is conserved at Manas National Park of West Bengal.

Ans. False

SUB-TOPIC – 4.3

ROLE OF JFM AND PBR IN BIODIVERSITY CONSERVATION SOME ENDANGERED SPECIES OF INDIA AND THEIR CONSERVATION

SUMMARY

Many organisations take part in conservation of biodiversity. But one of organisation which play major and most important role in biodiversity conservation in India is JFM.
The full form of JFM is joint forest management. It is regulated by Govt. of India. It was first implemented successfully in Arabari forest of Medinipur for conservation of sal tree. Local people take part in this programme.
Another organisation other than JFM is PBR. The full form of PBR is peoples’ biodiversity register. According to biodiversity act 2002, a data bank is prepared, where the comprehensive information on availability and knowledge of local biological resources and their way of usage are registered is called PBR.
Various measures are taken for conservation of certain animals like lion, tiger, crocodile, red panda etc. in India. In Sundarban biospere reserve tiger is conserved, in Manas national park rhino, in Gir national park lion, in Bhitarkanika, crocodile and in Barsi red panda isonserved.

Long Answer Type Questions

1. Briefly describe the concept of JFM and PBR and the role in conservation of biodiversity.

Part Question, Discuss any two roles of People’s Biodiversity Register (PBR) in Conserving local biodiversity

Part Question, What are the roles of forest Management in the conservation of biodiversity.

Ans. Joint Forest Management or JFM

The proper management of biodiversity by the joint action of local people and the forest department of the state government which is approved by Indian government, is known as Joint Forest Management or JFM.

Role of JFM in conservation of biodiversity: In conservation of biodiversity, the role of JFM is as follows-[1] The committee, formed by the local residents of any forest area, maintains a coordination with the state forest department regarding the conservation of the biodiversity of that forest. [2] The JFM committee members keep a vigil on the forest area along with their daily activities regarding forest fire, encroaching of the forest area, poaching, felling of trees etc. and report it immediately to the forest department in case of any adversity.

Peoples’ Biodiversity Register or PBR

It is a ready reference prepared by the central forest department in accordance with the Biodiversity Law 2002. This document contains detailed information on the availability of local biodiversity, their habits and habitats, other behaviours, their ecological importance etc.

Role of PBR in conservation of biodiversity: In conservation of biodiversity, the role of PBR is as follows-[1] PBR provides correct information about the biodiversity of local area so that, the rare and endangered animals and plants can be conserved properly. [2] It makes people aware of the importance of conservation of biodiversity and involves them directly with the conservation project. [3] PBR makes the people aware of the sustainable utilisation of forest resources and helps in economic development of the area. [4] PBR provides correct geographic information about conserved area. [5] Identify endangered species and collect information about conservation of these species. [6] Gather knowledge about local species and their cultural and social value. [7] Gives idea about the obtained product from species and their value along with their collection and transport procedure.

2. Mention the causes of decrease in tiger population in India. Briefly describe the measures taken to protect tigers.

Ans. Causes of decrease in tiger population

The causes which resulted in the decrease of population of tigers are mentioned below.

Poaching: The value of tiger skin is as high as 12500 $ in the international markets. The bones, teeth, claws also attract poachers to kill tigers indiscriminately.
Squeezing of natural habitat: With the increase in human population, the forest areas are being encroached for building residential places. As a result, the normal habitats of tigers are being squeezed. This is one of the most important causes of decrease in tiger population.
Problem in reproduction: Tiger prefer dense forest for breeding. With continuous human intervention, their natural breeding habitat is being disturbed. Moreover, due to the absence of partner, the number of tigers is decreasing.

Measures taken to protect tigers

In 1969, a general meeting of IUCN was held in New Delhi. Based on the resolution of that meeting, killing of tigers was banned since 1970. After two years, Government of India framed and implemented the Wildlife Conservation Act (1972). In 1973, a committee, named National Tiger Conservation Authority (NTCA) was formed by the Government of India under the recommendation of IUCN and WWF. It was the first step exclusively for conservation of tigers in India. Primarily, the conservation project was started in nine sanctuaries in 1973. Now there are 42 different project running in this country. Out of them Jim Corbett National Park in Uttarakhand is an important tiger conservation centre in India.

3. Mention the causes of decrease in the population of rhino in India. Briefly describe the measures taken to protect rhinos.

Part Question, Summarize which conservation measures have been adopted to increase the population of an endangered mammal exclusively found in the swampy grasslands under the foothills of the Eastern Himalaya.

Ans. Causes of decrease in the population of rhino in India

The causes which resulted in the decrease of population of rhino are mentioned below.

Squeezing of natural habitat: Due to increasing human population, the forest areas are being encroached for human residential purpose. As a result, the normal habitats of rhinos are being decreased. This is one of the most important causes of decrease in the population of rhino.
Poaching: The value of rhino horn is very high in the East Asian markets. People there have a baseless belief that the rhino horn has immense medicinal importance. For this the purpose, poachers kill rhinos indiscriminately and cut their horns.
Low birth rate: The rhinos have very low birth rate. The gestation period is very long (479 days). That is why the population size does not grow quickly.

Measures taken to protect rhinos

About 85% of the single-horned rhino (Rhinoceros unicornis) are found in Assam. Due to certain human actions, the number of the rhino population was decreasing very fast. In view of this fact WWF (World Wildlife Fund for Nature) and the forest department of Assam have jointly taken an initiative named IRV 2020 (Indian Rhino Vision 2020). The objective of this project is to increase the population of rhinos to 3000 by the year 2020. The success of the project has already been established. The number of rhinos in Assam reached 2544 in 2013. According to the census of 2013, the population of rhinos is exclusively in the Kaziranga National Park reached 2319 from 1855. Regular surveillance, restricted ecotourism and strong implementation of laws have made the project successful. Rhino conservation has also become an integral part of several other national parks. Gorumara National Park is one of them.

4. Mention the causes of decrease in lion population in India. Briefly describe the measures taken to protect lions.

Ans. Causes of decrease in lion population in India

The causes which resulted in the decrease of population of lion are mentioned below.

Squeezing of natural habitat: Due to increasing human population, the forest areas are being encroached for human residential purpose and cultivation. As a result, the normal habitats of lions are being squeezed. Railway tracks and roadways through the forest result in accidental death of the lions.
Poaching: The value of lion skin is very high in the international markets. The bones are used in ayurvedic medicines. Some people like to keep the teeth and nails of lions in their collection as a sign of power. Due to this, the poachers kill lions indiscriminately.

Measures taken to protect lions

Centuries back asiatic lions were available in many west Asian countries, Due to indiscriminate hunting, the population is reduced to a few. King of Junagarh was the first person to take a move towards conservation of lions. He banned hunting of lions in 1910. The ban was continued even after independence. In 1960 and 1970, Gir forest was declared as sanctuary and national park respectively. To protect Asiatic lions, state government of Gujarat has taken an initiative named Gir Lion Project. Since 1974, the population of lions, started increasing. According to the census 2015, the number of lions in Gir National Park is 523. In the year 2015 gradually the central ministry of environment formed a high level committee named ‘Asiatic Lion Re-introduction Project’ for the conservation of Gir lions.

5. Mention the causes of decrease in crocodile population in India. Briefly describe the measures taken to protect crocodiles.

Ans. Causes of decrease in crocodile population in India

The causes which resulted in the decrease of population of crocodile are mentioned below.

Poaching: The demand for crocodile skin is very high in international market. For this purpose, poachers kill crocodiles indiscriminately.
Loss of egg: Crocodile eggs are often eaten up by jackals. Many people also consume there eggs Therefore, the birth rate of crocodiles goes down.
Killing by fisherman: Crocodiles, often trapped in the fishermen’s net are killed. This also decreases the number of crocodiles.

Measures taken to protect crocodiles

To conserve crocodiles, Crocodile Conservation and Research Project was taken up by the government in 1974. In the next year, another project named Crocodile Breeding and Management Project or Project Crocodile was started. This project was spread in 11 crocodile sanctuaries and 16 crocodile rehabilitation centres. To train up competent personnel, the Crocodile Breeding and Management Training Centre is established in Hyderabad in 1980. Bhitarkanika sanctuary is a renowned crocodile conservation centre in Odisha.

6. Mention the causes of decrease in red panda population. Briefly describe the measures taken to protect red pandas.

Ans. Causes of decrease in red panda population

The causes which resulted in the decrease of population of red pand are mentioned below.

Loss of habitat: Regular human interventions in forests for collection of wood, indiscriminate felling of bamboo trees reduce the size of their natural habitat. They usually feed on the leaves of bamboo. Due to the felling of bamboo trees red pandas are dying of starvation.
Poaching: The soft, reddish brown fur and striated bushy tails of red pandas have always been in very high demand. That is why, poachers indiscriminately kill this beautiful animal.
Killing by stray dogs: Red panda is a slow moving animal. They are often attacked by stray dogs and are killed.

Measures taken to protect red pandas

Red panda is an endangered animal. To keep this animal in the race of life, certain conservational measures have been taken. In 2005, state government of Sikkim and Arunachal Pradesh have taken a joint project with the recommendation of the WWF. Red panda conservation projects are running in Varsey Rhododendron Sanctuary and Kangchenjunga Biosphere Reserve of Sikkim. For this purpose, collection of bamboo and other wood from these forests are banned completely. About 200 local residents are trained to prepare fuel briquettes with agricultural wastes and mod, to supplement wood and bamboo. In Arunachal Pradesh, the habitats of red panda are taken under the vigil of Community Conserved Area (CCA), where local people are made involved in the conservation of this beautiful endangered animal.

Short Answer Type Questions

1. Mention three tiger conservation centres in India.

Ans.Three figer conservation centres in India are (1) Sundarban in West Bengal, [2] Corbett tiger reserve in Uttarakhand and [3] Kanha National Park in Madhya Pradesh.

2. How and where was JFM established?

Ans. In 1971, to prevent indiscriminate felling of trees and grazing in the forest of Arabari in West Midnapore, the forest officer of that time, Dr. Ajit Kumar Banerjee, formed a forest protection. committee with the local people. By this process, the first JFM came into being. The members planted several saplings of Sal tree in the Arabari area to expand the forest and by 1988, they grew Sal trees of a worth of 12.6 million rupees.

3. Name few committees working under JFM.

Ans.There are several cominittees working under JFM, Pew committees under JFM are Forest Protection Committee (FPC), Eco Development Committee (EDC), Village Forest Committee (VFC) etc.

4. Name few animals that are protected in Kaziranga National Park.

Ans.Numerous animals are protected in Kaziranga National Park. The animals protected in Kaziranga National Park are one-horned rhinos, sambar, wild hog, hog deer, Indian muntjac etc.

5. What are world heritage sites?

Ans.World Heritage Convention (WHC), a wing of UNESCO, looks out for any natural place or any man-made structure with outstanding natural, geographical or historical importance. To provide special protection to these places, WHC designate them as a world heritage sites. ExampleSundarban Biosphere Reserve.

6. What is CITES?

Ans. According to the proposal of IUCN (1963) in Washington, a convention named CITES (Convention on International Trade in Endangered Species of Wild Flora and Fauna) was formed in 1975. Since its inception, this body had banned the illegal trading of endangered or rare animal and plant products and body parts on a global basis. By this action, the indiscriminate hunting and selling of endangered species have reduced significantly.

7. Why is Sundarban treated as a world heritage site?

Ans. The mangrove forest of Sundarban is the largest of its kind. It shelters several endangered fauna and flora including the famous Royal Bengal tiger. The root system of the dense mangrove trees prevents soil erosion and protects the area from storm. Sundarban is very rich in forest resources.

Therefore, Sundarban is designated as a world heritage site.

8. What is meant by out of danger species?

Ans. By the process of conservation, the number or population of certain species, which had once become endangered, have increased significantly. These species are treated as out of danger species. Example-Spotted deer.

9. What are extinct species?

Ans. The species of plants or animals that can no longer be seen living anywhere in the wild or in captivity, are called extinct species. ExampleDodo, passenger penguin, Carolina parakeet etc.

10. What is project tiger

Ans. Project tiger is a project for conservation of tiger in India sorted by indian govt. in 1973. This project is maintained by national tiger conservation authority.

11. What is meant by endangered species?

Ans. Due to human intervention, pollution, lack of food and squeezing of native habitat, the rate of reproduction of certain animals and plants is getting reduced to such an extent that, they are on the verge of extinction. These species are called endangered species. Example- Nilgiri langur, snow leopard etc.

12. Hilsa, Bee, Penguin, Rauwolfia-Asscess which are the causes of endangeredness of the above mentioned organisms.

Ans. Hilsa- Facing threat due to overexpoloitation of hilsa population.

Bee-Loss of habitat, excessive use of cell phones that projects electromagnetic waves, damages the ability of bees to return to their colony. By that way it destroy the navigation system of bees.

Penguin-Penguin faces threats from geological events like volcanic erruption, pol climatic changes and severe weather.

Rauwolfia-This type of medicinal plant facing threat due to overexploitation.

13. Write down two steps to increase of the number of one-horned rhino in India.

Or, Propose two conservation measures that could be taken to increase the number of Indian one-horned rhino.

Ans. Two steps, that are taken to increse the number of one-horned rhino in India are[1] Increase the habitat and food souce of one horned rhino [2] Arrangement of breeding programme or increased the number of rhino by captive breeding.

14. What is red data book?

Ans. For the conservation of rare and endangered animals and plants, IUCN publish a book comprising detailed information regarding the rare and endangered organisms all over the earth. This book is known as the red data book. In this book, the organisms are classified under nine different classes according to their availability status like extinct, endangered, vulnerable etc.

15. What is captive breeding?

Ans. Breeding of animals in controlled environment and in a scientific way in a sit with consrevation facilities is called captive breeding In case of rhino, red panda this process is applied.

16. What are the steps taken in Gir national park to increase number of lions?

Or, Mention the in-situ measures adopted for conservation of lion in Gir National park of India.

Ans. Steps for conservation of lion in Gir national park to increase the number of lions are-[1] The natural habitat of Gir national park needs to be protected. [2] Wild animals and plants should be conserved in Gir national park, so that the food supply and shelter for the lion could be maintained. [3] Captive breeding are taken as a potential tool to increase the population of lion. [4] Electric fence should be avoided.

17. What are the main buds to protect biodiversity?

Ans. Main acts to protect biodiversity are-[1] The wildlife protection act (1972) [2] The forest conservation act (1980) [3] The environment protection act (1986) [4] Biological diversity act (2002).

18. What are the informations documented in PBR?

Or, Write the major topics rgarding biodiversity documented in people’s Biodiversity Register (PBR).

Ans. Main acts to protect biodiversity are-[1] The wildlife protection act (1972) [2] The forest Major topics that documented in PBR are[1] PBR provides correct information about the biodiversity of local area so that, the rare and endangered animals and plants can be conserved properly. [2] It makes people aware of the importance of conservation of biodiversity and involves them directly with the conservation project. [3] PBR makes the people aware of the sustainable utilisation of forest resources and helps in economic development of the area. [4] PBR provides correct geographic information about conserved area.

19. Write the in-situ conservation measures taken for one endangered reptile species and name one site of such conservation in West Bengal.

Ans. One is endangered reptile crocodile. Measures taken for in-situ conservation of crocodile are-[1] Protect remaining population of crocodilians in their natural habitat by creating sanctuaries. [2] Promote captive breeding. [3] Prevent poaching of crocodile and as well as their eggs.

Name of such conservation in West Bengal is Bhagabatpur crocodile project, Sundarban.

Very Short Answer Type Questions

Multiple Choice Questions & Answers [MCQ]

1. Rhinoceros is the state animal of-

A. Tripura

B. Assam

C. Uttarakhand

D. Arunachal Pradesh

Ans. B

2. Tiger project was implemented in India in-

A. 1967

B. 1973

C. 1983

D. 1987

Ans. B

3. The organisation that publishes the list of endangered species is-

A. BBC

B. UNO

C. WWF

D. IUCN

Ans. D

4. The organisation that publishes red data book is-

A. WWF

B. IUCN

C. IMF

D. FAO

Ans. B

5. In India, lions are conserved in-

A. Gir forest

B. Jim Corbett National Park

C. Kanha National Park

D. Jaldapara National Park

Ans. A

6. In West Bengal, Singalila National Park is situated in the district-

A. Cooch Behar

B. South 24 Parganas

C. Darjeeling

D. Malda

Ans. C

7. In West Bengal, rhinoceros is conserved in-

A. Sundarban

B. Jaldapara

C. Bethuadahari

D. Forest of Purulia

Ans. B

8. The red data book comprises information about-

A. Animal species of the Red Sea

B. Tigers of Sundarban

C. Endangered species

D. Revolutionary activities

Ans. C

9. Natural habitat of Indian lion is-

A. Simlipal forest of Odisha

B. Betla forest of Bihar

C. Gir forest of Gujarat

D. Kaziranga National Park of Assam

Ans. C

10. The animal which is conserved in Padmaja Naidu Himalayan Zoological Park is-

A. Snow leopard

B. Red panda

C. Himalayan wolf

D. All of these

Ans. D

11. The full form of JFM is-

A. Joint Feature Management

B. Judicial Forest Management

C. Jungle Fire Management

D. Joint Forest Management

Ans. D

12. The district in West Bengal where the concept of JFM was first implemented, is-

A. West Midnapore

B. Howrah

C. Kolkata

D. Nadia

Ans. A

13. The year in which the concept of JFM was first implemented is-

A. 1976

B. 1985

C. 1963

D. 1971

Ans. D

14. Number of Asiatic lions in Gir National Park (as per census 2015) is-

A. Less than 50

B. More than 500

C. More than 1000

D. Less than 500

Ans. B

15. Objective of IRV is the conservation of-

A. Royal Bengal tiger

B. Indian rhino

C. Asiatic lion

D. Gangetic crocodile

Ans. B

16. NTCA works for the welfare and protection of-

A. Royal Bengal tigers

B. Indian rhinos

C. Asiatic lions

D. Gangetic crocodiles

Ans. A

17. Decide which of the following project tiger is located within our state?

A. Bandipur

B. Simlipal

C. Sundarbans

D. Kanha

Ans. C

18. Kaziranga National Park is famous for conservation of-

A. Deer

B. Elephant

C. Rhinoceros unicornis

D. Lion

Ans. C

19. Biological diversity act in India was introduced in-

A. 1992

B. 1996

C. 2000

D. 2002

Ans. D

20. Singalila National Park is situated in which of the following district-

A. Cooch Behar

B. Darjeeling

C. Malda

D. South 24 parganas

Ans. B

21. Wildlife portection act was introduced in –

A. 1962

B. 1972

C. 1982

D. 1992

Ans. B

Answer in a single word or sentence

1. Write the full form of PBR.

Ans. Peoples’ Biodiversity Register

2. Write down the full form of CITES.

Ans. Convention of International Trade in Endangered Species of Wild Fauna and Flora

3. Write the full form of IUCN.

Ans. International Union for Conservation of Nature and Natural Resources

4. Write the scientific name of Indian tiger.

Ans. Panthera tigris

5. Write the scientific name of Indian rhino.

Ans. Rhinoceros unicornis

6. Write the scientific name of Asiatic lion.

Ans. Panthera leo persica

7. Write the scientific name of gharial.

Ans. Gavialis gangeticus

8. Write the scientific name of brackish or salt water crocodile.

Ans. Crocodylus porosus

9. Write the scientific name of red panda.

Ans. Ailurus fulgens

10. In which part of Odisha there is a crocodile project?

Ans. A crocodile project is situated in Bhitarkanika of Odisha.

11. What is the full form of NTCA?

Ans. National Tiger Conservation Authority

12. Where did the first JFM start?

Ans. The first JFM was started in Arabari forest of West Midnapore.

13. Who was the first person to conduct JFM?

Ans. Dr. Ajit Kumar Banerjee, the Divisional Forest Officer (DFO) of Midnapore, was the first person to conduct JFM.

14. By which law is PBR regulated?

Ans. Biological Diversity Act, 2002

15. Which committee was formed by PBR?

Ans. PBR formed Biodiversity Management Committee (BMC).

16. Wrie down the names of few committee work under JFM.

Ans. Forest protection committee (FPC), Ecodevelopment Committee (EDC), Village forest committee (VFC).

17. Which committee form PBR?

Ans. Biodivesity management committee or BMC

18. Write down the name of Indian tiger conservation project.

Ans. Project tiger

19. Write down the name iof Indian forest conserving tiger.

Ans. Sundarban

20. Write down the name of project of Indian rhino conservation.

Ans. Indian rhino vision 2020

21. Name one area of India for rhino conservation.

Ans. Kaziranga national park

22. Give one example of crocodile project.

Ans. Bhagabatpur crocodile project, West Bengal

23. Write dwn the name of one captive breeding site of India..

Ans. Nandankanan of Orissa

24. Name one zoological park of West Bengal under project Red Panda.

Ans. Padmaja Naidu himalayan zoogical park, Darjeeling

25. What is the full form of VFC.

Ans. Village forest committee

26. Write down the names of some endangered animals of India,

Ans. Indian elephant, Royal Bengal tiger, Red panda, Asian lion

27. What is the full form of IRV 2020

Ans. Indian rhino vision 2020

28. Name one endangered animal conservedat singalila national park.

Ans. Red panda or Clouded leopard.

29. Name the practice which jointly the local peoples and forest department maintain for reclamation of forest.

Ans. JFM or Joint Forest Management.

Fill in the blanks

1. In India, about …………. % of rhinoceros inhabit Assam.

Ans. 85

2. The Wildlife Protection Act was implemented in ………..

Ans. 1972

3. FPC is a committee under …………..

Ans. JFM

4. Maximum number of one-horned rhinos inhabit in the state of …………

Ans. Assam

5. Asiatic lions are conserved in ………… forest of Gujarat.

Ans. Gir

6. ………… types of crocodiles are found in India.

Ans. Three

7. The …………. Wildlife Sanctuary in Odisha has a crocodile breeding centre.

Ans. Bhitarkanika

8. The other name of red panda is ………….

Ans. Firefox

9. The ……….. Biosphere Reserve is the present conservation centre for red panda.

Ans. Kanchenjunga

10. The first JFM of West Bengal was formed in the year ………..

Ans. 1971

11. Highest number of rhino is found in ………… state of India.

Ans. Assam

12. ………… is conserved under IRV 2020 project.

Ans. Rhino

13. Lion is found in ……….. forest of India.

Ans. Gir

14. Red panda is the state animal of ……….. state.

Ans. Sikkim

15. ………….. sanctury of odisha is a crocodile conservation center.

Ans. Bhitarkanika

16. The first JFM in West Bengal was introduced in ………… forest.

Ans. Arabari

State true or false

1. According to the census of 2014, the number of tigers in India is 1412.

Ans. False

2. The only conservation centre for Asiatic lion is situated at Gir, Gujarat.

Ans. True

3. The concept of JFM was initiated in the year 1975.

Ans. False

4. JFM was first introduced in Sundarban of West Bengal.

Ans. False

5. PBR mainted by local law.

Ans. False

6. Lion is conserved in Gir forest of India.

Ans. True

7. Indian lion is an endangered animal.

Ans. False

8. One-horned rhinocerous is conserved a Manas National park of West Bengal.

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