RBSE Solutions for Class 11 Biology Chapter 41 Environmental Pollution

Rajasthan Board RBSE Class 11 Biology Chapter 41 Environmental Pollution

RBSE Class 11 Biology Chapter 41 Multiple Choice Objective Questions

Question 1.
The main reason of pollution in Metropolitan (big) cities –
1. Domestic fuel
2. Vegetation
3. Increased population
4. Motor vehicles

Question 2.
Sound pollution is measured in –
1. kg
2. dB
3. DU
4. Hz

Question 3.
Sound level during normal conversation –
1. 10-12 dB
2. 30-60 dB
3. 70-90 dB
4. 120-150 dB

RBSE Solutions for Class 11 Biology Chapter 41 Environmental Pollution

Question 4.
Which pollution causes acid rain –
1. Pesticides
2. SO2 and NO2
3. Carbon particles
4. Dust particles

Answers :
(1). 4
(2). 2
(3). 2
(4). 2

RBSE Class 11 Biology Chapter 41 Very Short Answer Questions

Question 1.
When the world pollution day is celebrated ?
Answer :
July 11

Question 2.
Most affected country from the ozone hole is?
Answer :
Australia

Question 3.
Reason of itai-itai disease is ?
Answer :
Weak and brittle bones

Question 4.
The main pollutant in exhaust of motor vehicles.
Answer :
CO

RBSE Solutions for Class 11 Biology Chapter 41 Environmental Pollution

Question 5.
What is Smog ?
Answer :
Mixture of O3, PAN and NO

Question 6.
Which pollution is damaging the Taj Mahal ?
Answer :
SO2

Question 7.
Which sound level is considered as sound pollution.
Answer :
80 dB

Question 8.
Which system get affected in Minamata disease ?
Answer :
Nervous system

Question 9.
Which are the biodegradable pollutants ?
Answer :
Remnants of plants and animals

Question 10.
Which are the non-biodegradable pollutants ?
Answer :
DDT, BHC, 2-4D, Plastic etc.

RBSE Solutions for Class 11 Biology Chapter 41 Environmental Pollution

Question 11.
Which are the nuclear pollutants ?
Answer :
Waster of nuclear reactors

Question 12.
Is nuclear pollution possible by natural source ?
Answer :
Yes

Question 13.
Give one measure to stop nuclear pollution.
Answer :
Prohibition of atomic blasts.

RBSE Class 11 Biology Chapter 41 Short Answer Questions

Question 1.
Define soil pollution ?
Answer :
Land is a part of the earth and upper part of the land is called as Soil. Earth is called as “Mother” as it provides nutrients and food for all living organisms. There are specific physical, chemical and biological properties of the soil. Any change in these properties is termed as soil pollution.

Question 2.
Write the main pollutants causing air pollution.
Answer :

  1. Gases: Burning of fuel in houses and industries release gases such as CO, CO2, Hydrocarbons, NO, N2O ,. H2S etc. They are harmful to the life in many ways.
  2. Chemicals: Many non-gaseous harmful chemicals such as arsenic, benzene, cadmium, chlorine, fluoride, formaldehyde. hydrogen fluoride, manganese, nickle, lead etc. are released in many industries. Such as coal and oil furnaces, glass industry, refineries, steel plants, motor vehicles, fertilizer plants, power houses etc. These chemical impose serious threat to the health.
  3. Particular Matter : Particulate matter are the main factor of air pollution. They may be in solid or liquid or colloidal state in air.

RBSE Solutions for Class 11 Biology Chapter 41 Environmental Pollution

Question 3.
Write the main pollutants causing water pollution.
Answer :
Sewage and domestic wastes; Industrial wastes; Pesticides; Chemical fertilizers; Thermal pollution; Oil Pollution.

Question 4.
Write the main pollutants of sound pollution.
Answer :
The various sources of sound pollution are as follows :

  1. Noise by Industries : The mechanization increased the production but simultaneously the sound pollution is also increased. This sound pollution indirectly harmful for out health. In various industries, the sound level is increasing 120 dB or more.
  2. Noise by Aeroplanes : Aeroplanes are the bigger sources of noise pollution. They produce sound of 150 dB or more. The houses and building develop around the airports develop cracks and the persons residing close to airports losing hearing and developing irritability.
  3. Noise by Motor Vehicles : Numbers of motor vehicles is increasing with the population to provide transportation. They are causing noise pollution which is more in big cities like Delhi, Kolkata, Mumbai, Chennai etc.
  4. Noise by Loud speakers and Generators : Nowadays, the use of loudspeaker is increased in various programs, as a result sound pollution is in-creased enormously.

Question 5.
What are the main pollutants of soil pollution.
Answer :
Land is a part of the earth and upper part of the land is called as Soil. Earth is called as “Mother” as it provides nutrients and food for all living organisms. There are specific physical, chemical and biological properties of the soil. Any change in these properties is termed as soil pollution.

RBSE Solutions for Class 11 Biology Chapter 41 Environmental Pollution

Question 6.
What are the side effects of sound pollution.
Answer :
Effects of Sound Pollution :
The various harmful effects of sound pollution are as follows:

  • Gradual loss of hearing and may be complete deafness.
  • It causes irritability and restlessness.
  • It may cause ulcers in the small intestine.
  • Sudden excessive sound may lead to abortion.
  • Insomnia.
  • Reduce in working capacity.
  • Loss of hunger
  • Increase in B.P.

Question 7.
How air pollution can be checked ?
Answer :
Control of Air Pollution :

  • Old motor vehicles cause more pollution. Therefore, their use should be prohibited.
  • Use of catalic converter in the motor vehicles that minimizes the air pollution by removing more harmful gases.
  • Use of alternate fuel in the motor vehicles such as in Delhi, CNG (Compressed Natural Gas) is used in the buses and autos. In big cities electrical public transports like electric buses, railways should be used.
  • In motor vehicles, 2-stroke engine causes more pollution. Therefore, they should be replaced by 4-stroke engine vehicles.
  • Use of electricity generator should not be permitted in cities.
  • Nuclear tests must be banned totally.
  • Modem techniques should be used in the industries to reduce smoke. In houses, gas burners or smokeless burners should be used.
  • Particulate matter can be removed from the air using electrostatic precipitation.

Question 8.
What are the main ill effects of water pollution.
Answer :
Harmful effects of Water Pollution :
Water pollution causes many types of deterimental effects such as –

  1. Sewage polluted water may cause typhoid, diarrhea, Jaundice, Cholera etc.
  2. Contact of soil containing human excreta may cause infection of many types of worms such as hook worm, Ascaris etc.
  3. Bathing in polluted water may cause weil’s disease, schistosomiasis and other skin diseases.
  4. Drinking of polluted water having DDT, BHC etc. may cause abortion and embryonic abnormalities. There is bio magnification of non-biodegradable pollutants i.e. there concentration increases in higher tropic levels.
  5. Industrial waste may cause diseases related to liver, kidney, brain etc.

RBSE Solutions for Class 11 Biology Chapter 41 Environmental Pollution

Question 9.
Why pollution control is required ?
Answer :
Pollution control is needed to preserve precious environment resources and to improve the environment quality.

Question 10.
Write the chemical names of the main pollutants.
Answer :
Many non-gaseous harmful chemicals such as arsenic, benzene, cadmium, chlorine, fluoride, formaldehyde, hydrogen fluoride, manganese, nickle, lead etc. are released in many industries. Such as coal and oil furnaces, glass industry, refineries, steel plants, motor vehicles, fertilizer plants, power houses etc. These chemical impose serious threat to the health.

Chemical fertilizers are used to provide nutrients to the crop. They contain various types of chemicals which impose harmful effects on the animals and human beings.

RBSE Class 11 Biology Chapter 41 Essay Type Questions

Question 1.
Write the definition, factors and prevention of air pollution ?
Answer :
When the pollutants pollute the air and cause deter mental effects on the human beings, plants and animals is called as air pollution. It includes mainly the toxic gases. Sources of Air Pollution: They are as follows :

1. Motor Vehicles : Motor Vehicles are one of the major source of air pollution and their increasing number imposing a serious problem. Diesel is comparatively more harmful than the petrol. The diesel vehicles produce black smoke exhaust that contains CO, CO2, hydrocarbons, compounds of nitrogen and sulphur. These components impact toxic effects.

2. Combustion of fuel (Wood and Coal) : The burning of fuel in houses and industries produce many types of harmful gases such as CO, CO2, SO2 on complete combustion. The oil refineries and thermal power houses release smoke that contains SO2, CO2, H2S gases etc. which are toxic. Many chemical industries release lethal elements such as HCl, Cl, NO, Hg, Cu, Pb, As, Zn etc. which are toxic to human beings and other animals.

3. Nuclear Test : Many countries performed nuclear test such as America, Germany, France, Russia etc. Recently, India and Pakistan also had nuclear tests. The nuclear tests result in increase in amount of radio-active particles which impose detrimental effects on huntan beings, plants and animals. They cause serious diseases. For example chamobyle disaster occurred in USSR. In this awful event, a blast in the atomic reactor released large amount of radiations in the atmosphere.

4. Power Generators : Increase in electricity consumption is increasing because of urbanization, industrialization etc. The generation of the electricity is less than its consumption. Therefore, domestic generators are in use to produce electricity. They are causing both sound and air pollution. The smoke generated by these generators cause irritability and respiratory diseases.

Main Air Pollutants :
1. Gases : Burning of fuel in houses and industries release gases such as CO, CO2, Hydrocarbons, NO, NO2, H2S etc. They are harmful to the life in many ways.

2. Chemicals : Many non-gaseous harmful chemicals such as arsenic, benzene, cadmium, chlorine, floride, farmaldehyde, hydrogen floride, manganese, nickle, lead etc. are released in many industries. Such as coal and oil furnaces, glass industry, refineries, steel plants, motor vehicles, fertilizer plants, power houses etc. These chemical impose serious threat to the health.

3. Particular Matter : Particulate matter are the main factor of air pollution. They may be in solid or liquid or colloidal state in air.

Harmful effects of Air Pollution :
Air pollution is a contribution of modem industrialization that disturbs the ecosystem and causes serious health problems for living beings which are as follows :
A. Effect of air pollution on Human health :

  • It causes respiratory diseases such as bronchitis, pain in the throat, lung cancer, silicosis etc.
  • SO2 and NO2 cause emphysema, cancer and blood vascular diseases; eye irritation etc.
  • Smog (a combination of Ozone, PAN and NO) is too very harmful. It is also called as brown air. It causes lung diseases.
  • Lead present in vehicle exhaust cause multiorgan toxicity such as it damages liver, bones, lungs a nervous system etc.
  • Silicosis disease develops in the workers working in stone industries and mining.

B. Effect of air pollution on Vegetation :
Air pollution badly effect the vegetation. It reduces photosynthesis, falling of leaves, colourless or black leaves due to SO2, falling of flowering buds, less fruit formations etc.

C. Effect of air pollution on Animals :
Air pollution is detrimental for animals particularly insects such as honey bees, grasshoppers etc.

D. Effect of air pollution on Ozone :
Ozone layer protects the earth life from U-V rays. The chlorine and fluorine radicles harm the ozone which are produced by CFC (chloro-floro-carbon). The CFC is mainly used in refrigeration industries.

E. Green House Effect :
Air pollution, particularly excess of green house gases such as CO2, causes green house effect which in turn results in global
warming.

F. Acid Rain :
Air pollution of SO2 and NO2 result in acid rain. The SO2 reacts with water to form sulfuric acid and NO, forms nitric acid. The acid rain destroys forests and historical monuments like Taj Mahal etc.

Control of Air Pollution :

  1. Old motor vehicles cause more pollution. Therefore, their use should be prohibited.
  2. Use of catalic convector in the motor vehicles that minimizes the air pollution by removing more harmful gases.
  3. Use of alternate fuel in the motor vehicles such as in Delhi, CNG (Compressed Natural Gas) is used in the buses and autos. In big cities electrical public transports like electric buses, railways should be used.
  4. In motor vehicles, 2-stroke engine causes more pollution. Therefore, they should be replaced by 4-stroke engine vehicles.
  5. Use of electricity generator should not be permitted in cities.
  6. Nuclear tests must be banned totally.
  7. Modem techniques should be used in the industries to reduce smoke. In houses, gas burners or smokeless burners should be used.
  8. Particulate matter can be removed from the air using electrostatic precipitate.

RBSE Solutions for Class 11 Biology Chapter 41 Environmental Pollution

Question 2.
Write the pollutants, harmful effects and control of water pollution.
Answer :
Many undesirable and harmful inorganic, organic or biological elements pollute the water. Such pollutants harm the life as most of the part of protoplasm is made up of water.

The problem of getting fresh drinking water is increasing all over the world. The pure drinking water should be neat, tasteless, colorless, having pH value 7 to 8.5 and dissolved salts within permitted limit.

Sources and type of water pollution :
There are many sources and factors which cause water pollution. They may be natural or human caused sources. The natural sources are difficult to control but human caused sources can be controlled. The human caused water pollutants are sewage, domestic wastes, industrial and agricultural wastes etc. Some of them are as follows –

1. Sewage and Domestic Waste :
They are the big threat to water pollution and it is increasing with increasing urbanization. They are released directly into rivers, ponds, lakes etc. Hence, their water get polluted. The sewage includes city garbage and human excreta etc. The sewage decrease O2 in the water which is lethal for aquatic life.

2. Industrial waste :
The industrialization is increasing along with the increase in human population. The industrialization is another big factor of water pollution. Many industries such as plastic, rubber, paper, soap, chemicals etc. release many harmful substances in the water. Some heavy metal (cadium, mercury) pollution develop diseases.

3. Pesticides :
Pesticides are used to protect the crop from harmful insects. These pesticide ultimately reach into the water bodies along with rain water. These chemicals of pesticides are determined to health.

4. Chemical fertilizers :
Chemical fertilizers are used to provide nutrients to the crop. They contain various types of chemicals which impose harmful effects on the animals and human beings.

5. Thermal Pollution :
The temperature of water bodies such as oceans, ponds etc. is increasing because of many industries, atomic blasts etc. This high temperature is harmful for the aquatic life such as fishes, algae etc.

6. Oil Pollution :
Crude oil (mineral oil) is transported using big ships through ocean routes. The spilling of this oil makes thick covering on the water. As a result the aquatic animals die of asphyxia.

Harmful effects of Water Pollution :
Water pollution causes many types of detrimental effects such as –

  1. Sewage polluted water may cause typhoid, diarrhea, Jaundice, Cholera etc.
  2. Contact of soil containing human excreta may cause in-fection of many types of worms such as hook worm, Ascaris etc.
  3. Bathing in polluted water may cause weil’s disease, schistosomiasis and other skin diseases.
  4. Drinking of polluted water having DDT, BHC etc. may casue abortion and embroyonie abnormalities. There is biomagnification of non-biodegradable pollutants i.e. there concentration increases in higher tropic levels.
  5. Industrial waste may cause diseases related to liver, kidney, brain etc.
  6. The polluted water also cause following diseases –
  • Mercury pollution causes minamata disease. It is a disease of nervous system. It causes numbness in feet, lips, tongue etc. paralysis in children and epilepsy.
  • Lead pollution causes diseases related to muscles and central nervous system.
  • Flouride pollution in water results in diseases called flourosis. It effects the teeth and bones. The legs bend outwards which is called as Knock Knee Syndrome.
  • Cadium pollution in water causes itai-itai or ouch-ouch disease.

Control of Water Pollution :

  1. Ecological stabilization is the most effective way to control water pollution.
  2. To make the public aware using movies, symposiums regarding ill effects of water pollution.
  3. Reuse of the wastes after recycling.
  4. Treatment of drinking water to make it suitable.
  5. Time to time quality checking of water bodies.

RBSE Solutions for Class 11 Biology Chapter 41 Environmental Pollution

Question 3.
Write the main pollutants, harmful effects and control of soil pollution.
Answer :
Land is a part of the earth and upper part of the land is called as Soil. Earth is called as “Mother” as it provides nutrients and food for all living organisms. There are specific physical, chemical and biological properties of the soil. Any change in these properties is termed as soil pollution.

Sources and Type of Soil Pollution :
1. Domestic Wastes :
Domestic wastes is a major cause of soil pollution in India, as we don’t have any developed system of disposal of wastes and we through it outside the houses. The domestic wastes include glass, plastic, polythene, kitchen waste, rusted iron etc. The problem of domestic waste is increasing with the urbanization.

2. Industrial Wastes :
Industrial waste is again a major cause of soil pollution. Because of poor enforcement & lack of proper monitoring, the industrialist do not use functional and effective waste disposal plants. They through the wastes here and there that causes soil pollution.

3. Agricultural Wastes :
The agricultural wastes again a cause of soil pollution. India is an agriculture dominated/ based country and 60 to 70% population is associated with agriculture. The agriculture waste is of two types –

  • Biodegradable – It includes rotten fruits and vegetables. They are degraded by the nature, hence are of less harm.
  • Non-biodegradable – It includes insecticides like DDT, BHC, Aldrin, Heptachlore etc. They are highly dangerous and remain in the soil for very long period.

4. Plastic Wastes :
Plastic waste is non-biodegradable, hence imposing serious threat to the pollution mitigation. We use polythene bags for our domestic use and are thrown here and there. There is no scientific and proper way to dispose plastic waste.

Effects of Soil Pollution :
Soil pollution is harmful directly and indirectly.

(a) Indirect effect :

  • House flies sit on the human excreta and later on the food items. They act as vector for many diseases like diarrhea, dysentery, cholera, typhoid etc.
  • Cockroaches live in the debris and in the Kitchen, they destroy our food. Hence, there are chances of infection of the food material.
    (iii) Sewage is used for the agriculture purpose. In long time, it reduces soil fertility.

(b) Direct effects :
Direct contact with polluted soil and intake of pollutants along with air cause allergy, asthma, enteritis, arthritis, skin diseases, TB etc.

Control of Soil Pollution :
Soil pollution can be controlled as follows :

  1. Proper disposal of the garbage, and not doing should be considered as a punishable crime.
  2. The License to put industry should be released only when there is a proper and scientific system of disposal of the wastes. The industries without proper management of waste disposal should be closed.
  3. Formation /Construction of Lavatories at every public place and in homes.
  4. Biological control of pest should be used in place of pesticides.
  5. Educating students at schools and colleges regarding the benefits of clean environment.

RBSE Solutions for Class 11 Biology Chapter 41 Environmental Pollution

Question 4.
Write the main pollutants, harmful effects and control of sound pollution.
Answer :
Definition :

  1. The disturbing or excessive noise that may harm the activity or balance of human or animal life is called as
    sound pollution.
  2. It is a form and level of environmental sound that is generally considered likely to annoy, distract or even harm other people.

Measurement of Sound Pollution :
The excessive of loudness of sound is called as sound pollution. The sound loudness is measured in decibal (dB) unit. i.e. decibel (dB) is the unit of measurement of sound loudness. It is measured with the help of Decibel meter or Larm barometer.

The unit of sound frequency is Hertz. The human capacity to hear sound is 20 to 20,000 Hertz.

80 dB or more sound loudness in the environment is called as sound pollution. The sound lever in normal conversation is 60 dB. The sound level above 90 dB is harmful for human beings. The upper tolerance limit of human beings is 120 dB. Some of the sound values of different sources are as follows :-

  • Audible sound — 15 dB or more
  • Quite office/room — 30 dB
  • Average home — 50 dB
  • Normal conversation — 60 dB
  • High ways — 60 dB or 80 dB
  • Shouting — 90 dB
  • Industries and Machine — 110 dB
  • Intolerable sound (DJ etc.) — 130 dB
  • Jet aeroplane sound — 150 dB
  • Rocket engine sound — 180 dB

Sources of Sound Pollution :
The various sources of sound pollution are as follows :

  1. Noise by Industries : The mechanization increased the production but simultaneously the sound pollution is also increased. This sound pollution indirectly harmful for out health. In various industries, the sound level is increasing 120 dB or more.
  2. Noise by Aeroplanes : Aeroplanes are the bigger sources of noise pollution. They produce sound of 150 dB or more. The houses and building develop around the airports develop cracks and the persons residing close to airports losing hearing and developing irritability.
  3. Noise by Motor Vehicles : Numbers of motor vehicles is increasing with the population to provide.transportation. They are causing noise pollution which is more in big cities like Delhi, Kolkata, Mumbai, Chennai etc.
  4. Noise by Loud speakers and Generators : Nowadays, the use of loudspeaker is increased in various programs, as a result sound pollution is increased enormously.
    To keep constant supply of electricity, generators are used in factories, markets and houses, The generators produce sound pollution.

Effects of Sound Pollution :
The various harmful effects of sound pollution are as follows:

  • Gradual loss of hearing and may be complete deafness.
  • It causes irritability and restlessness.
  • It may cause ulcers in the small intestine.
  • Sudden excessive sound may lead to abortion.
  • Insomnia.
  • Reduce in working capacity.
  • Loss of hunger
  • Increase in B.P.

Control of Noise Pollution :

  1. We have to control the noise in the industries by using proper measures. Industries should be in outer areas.
  2. Air ports should be far away from the population.
  3. Dense plantation is required around the industries and air ports.
  4. Use of loudspeakers and generators should be banned.
  5. Making the public aw are regarding deleterious effects of noise pollution.

RBSE Solutions for Class 11 Biology Chapter 41 Environmental Pollution

Question 5.
What can be the integrated solution to control all types of pollution’s. Explain.
Answer :
Nuclear Pollution and Disposal of Nuclear Wastes :
Radioactive uranium and plutonium are used in atomic reactors to obtain atomic energy by nuclear fission which in turn is used to generation electricity. The remnants of these nuclear reactors are called as nuclear waste. It is highly dangerous.

Atomic science is an important modem science which is used to make atomic bombs. Many countries like America, Germany, Russia, China, India, Pakistan etc. have power of atomic bombs. In 1945, America used atomic power in the two countries of Japan viz. – Hiroshima and Nagasaki and destroyed them. Our country has also become a atomic power country. Atomic energy can also be used in Medical field. Researches and Industries.

Atomic radiations released by atomic bombs and other radioactive substance cause radiation pollution which is highly lethal for human being, animals and plants. There is always a possibility of radiation pollution in atomic reactors.

Effect of Ionizing Radiation :
Alfa, beta and gamma radiations have detrimental effects on the tissues and they damage the cells. The radiation effects are both somatic and genetic.

Somatic effects of radiation includes – cataract in eyes, skin damage, detrimental effects on liver, spleen and thyroid and many types of cancer. The intensity of the damage depends upon the quantity of radiations.

Genetic effects cannot be seen in the same generation but they become visible in the next generation. The radiation damage the germ cells and cause chromosomal anomalies.

Radiations also effect vegetation’s and change their chromosomal composition Disposal of Nuclear Wastes

Nuclear waste disposal is a big problem, as it is highly hazardous and lethal. Following measures can help to minimize this problem –

  • Atomic blasts should be prohibited and a collective efforts is required by all the countries with nuclear power. Proper system and management is required to prevent any accident in the atomic power plants.
  • The leakage of the radio active material should be in permissible limit.
  • The radioactive waste is disposed in such a way that no pollution is caused. It should be buried deep underground.
  • The public should be removed immediately in case of any disaster emergency.
  • There should be no residential area near by the Atomic reactors.
  • There should be dense plantation around the atomic reactors.

RBSE Solutions for Class 11 Biology