UNIT - V Environmental 13 Issues CHAPTER

Chapter Outline

13.1 Pollution 13.2 Air Pollution 13.3 Water Pollution Environment is my prime teacher 13.4 Noise Pollution - Masanabu Fukuoka 13.5 Agrochemicals 13.6 Biomagnification 13.7 Eutrophication 13.8 Or ganic Farming and its clean environment is very necessary Implementation to live a peaceful and healthy life. But 13.9 Solid Waste Management A 13.10 Global Environment Change our environment is getting dirty day by day 13.11 Impact on Specific Ecosystem because of our negligence. Earth is currently 13.12 Ozone Depletion facing a lot of environmental concerns like air 13.13 Deforestation 13.14 Ecosan Toilets pollution, water pollution, and noise pollution, 13.15 Peoples Participation in Conservation global warming, acid rain, biomagnification, of Forests eutrophication, deforestation, waste disposal, ozone layer depletion and climate change. Over the last few decades, the exploitation of Learning Objectives our planet and degradation of our environment have gone up at an alarming rate. As our •• Gain knowledge about our environment and its actions have not been in favour of protecting importance. •• Get to know about the effects and after effects of this planet, we have seen natural disasters human activities on climate and ecosystem. striking us more often in the form of flash •• Realize the need and importance of forests. floods, tsunami and cyclones. •• Know about eco-friendly practices for pollution mitigation. “Every individual should be environmentally •• Acquire insights into solutions to aware, regardless of whether they work with environmental problems. environmental issues or not.” •• Understand the need for peoples’ participation in environmental protection. 13.1 Pollution •• Know about the global level Pollution is any undesirable change in the conventions on climate change. physical, chemical and biological characteristics •• Understand the importance of clean environment. of the environment due to natural causes and human activities. The agents which cause pollution are called pollutants. Pollution is

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TN_GOVT_XII_Zoology_chapter13.indd 235 25-02-2019 18:46:32 classified according to the types of environment continue to accumulate (biomagnification). that is affected. They are mainly air, water and Toxic elements like lead, mercury, cadmium, soil pollution. chromium and nickel are such common pollutants. 13.1.1 Classification of Pollutants In terms of eco-system, pollutants can 13.2 Air Pollution be classified into two basic groups – Non- Earth is surrounded by a gaseous envelope degradable and degradable. Based on the time which is called atmosphere. The gaseous taken to breakdown into their ingredients, blanket of the atmosphere acts as a thermal degradable pollutants are classified as rapidly insulator and regulates the temperature of degradable (non-persistent) and slowly the earth by selectively absorbing The UV degradable (persistent). rays of solar radiation. The adverse effects a) Rapidly degradable or non-persistent of pollution include depletion of Ozone pollutants: These can be broken down by by Chlorofluorocarbons or CFCs, used as natural processes. Domestic sewage and refrigerants and global warming by elevated

vegetable waste are examples of such pollutants. CO2 (industries, deforestation, and partial b) Slowly degradable or persistent combustion). pollutants: These are pollutants that remain The alterations or changes in the composition in the environment for many years in an of the earth’s atmosphere by natural or human unchanged condition and take decades or activities (anthropogenic factors) are referred as longer to degrade, as in the case of DDT. Air Pollution. Pollutants include the abundant c) Non-degradable pollutants: These presence of solid, liquid or gaseous substances cannot be degraded by natural processes. produced by human or natural activity. The Once they are released into the environment, nature and concentration of a pollutant they are difficult to be eliminated and determines the severity of detrimental effects

Pollutant emissions

Lightning Fertilizer

Wildfires Volcanoes Oil & Gas Cities Industry, power plants, Airplanes, Cars, Trucks, Sewage treatment Buses and Three & Two wheelers Natural Area Stationary Mobile

Fig. 13.1 Sources of air pollution. Environmental Issues 236

TN_GOVT_XII_Zoology_chapter13.indd 236 25-02-2019 18:46:33 on organisms and human health. Along with •• Area sources – agricultural - wood / atmospheric factors (humidity, precipitation, stubble burning, fireplaces wind, air currents, altitude) prevailing at a place •• Natural sources – wind-blown dust, and time, its effects can be far reaching and wildfires, volcanoes (Fig. 13.1). catastrophic. 13.2.2 Effects of Air Pollution Air pollutants can be •• Affects all organisms as they depend on the • discharge of dusts or particulate matter atmosphere for respiration. (PM: 2.5 ,10) •• Causes irritation in the throat, nose, lungs • discharge of gases (SO2, NO2, CO, CO2) and eyes. It causes breathing problems and Carbon monoxide (CO) is produced mainly aggravates existing health conditions such due to incomplete combustion of fossil fuels. as emphysema and asthma. Automobiles are major causes of CO pollution •• Contaminated air reduces the body’s in large cities and towns Automobile exhausts, defense mechanism and decreases the fumes from factories, emission from power body’s capacity to fight other infections plants, forest fires and burning of fire-wood in the respiratory system. contribute to CO pollution. •• Frequent exposure to polluted air increases With rapid urbanization, major amount of the risk of cardiovascular diseases. carbon dioxide and sulphur dioxide (SO2) is Breathing air that is filled with fine released in the atmosphere. From automobiles, particulate matter can induce hardening of aeroplanes, power plants and other human the arteries, triggering cardiac arrhythmia activities that involving the burning of fossil or even a heart attack. fuels (coal, oil etc.,) CO is the main pollutant 2 •• People who exercise outdoors can that is leading to global warming. sometimes be susceptible to adverse effects Nitrogen oxides are also major air of air pollution because it involves deeper pollutants. Fossil fuel combustion and and faster breathing. Hence it is advisable to automobiles exhausts are the source of walk or jog in the mornings in places with nitrogen oxides. Sulphur dioxide and nitrogen ample tree cover. oxides are the major causes of acid rain. •• Gas leaks can be lethal or affect the quality Particulate matters are tiny particles of of air in the affected area. solid matter suspended in a gas or liquid. •• CO in the atmosphere interferes with O Combustion of fossil fuels, fly ash produced 2 transport since haemoglopin has greater in thermal power plants, forest fires, asbestos affinity for carbon monoxide. At low mining units, cement factories are the main concentration it causes headache and sources of particulate matter pollution. blurred vision. In higher concentration, it 13.2.1 Sources can lead to coma and death. The main sources of air pollution are: •• Transport sources (Fig13.1) – cars, buses, Sameer, an App provides airplanes, trucks, trains hourly updates on the •• Stationary sources – power plants, National Air Quality Index incinerators, oil refineries, industrial (AQI) published by CPCB. facilities, and factories

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TN_GOVT_XII_Zoology_chapter13.indd 237 25-02-2019 18:46:33 13.2.3 Other notable effects of Air 13.2.4 Control of Air Pollution Pollution Certain measures help to remove pollutants, Smog is a type of air pollution caused by reduce their presence or prevent their entry into tiny particles in the air. The word comes from the atmosphere. a mixture of the words smoke and fog . •• Trees are the best remedy for urban Today, smog generally refers to photochemical particulate and gaseous pollution smog, which is created when sunlight reacts •• Forests act as carbon sinks and lungs of with nitrogen oxides and volatile organic the planet compounds found in fossil fuel emissions •• Catalytic converters in vehicles help to from automobiles, factories, and power plants. reduce polluting gases drastically These reactions create ground-level ozone and •• Diesel exhaust filters in automobiles cuts particulate matter, reducing visibility. Smog particulates can make breathing more difficult, especially for people with asthma. •• Electrostatic precipitators reduce release of industrial pollutants. Smog also affects plants and animals. It damages crops as well as causes health •• Cost effective air pollution treatment problems in pets, farm animals and human systems like indoor plants and high beings. Smog has also been known to cause performance biofilters can improve corrosive damage to buildings and vehicles. indoor air quality. Peroxyacetyl nitrate (PAN) is a secondary pollutant present in photochemical smog. It The Taj Mahal, a UNESCO world is thermally unstable and decomposes into heritage site, is facing deterioration and peroxyethanol radicals and nitrogen dioxide damage by industrial gases due to several gas causing eye irritation. industrial units around Agra. The white Global warming: Increase in the marble has decolorized to yellow. concentrations of greenhouse gases such as 13.2.5 Legal Protection CO2, methane, nitrous oxide, CFCs, and ozone

causes greenhouse effect, warming of the •• The Air (Prevention and Control of

earth, resulting in sea level rise, submerging of Pollution) Act was enacted in 1981 and islands and sea shores of various parts of the amended in 1987 for the prevention, world. control and abatement of Air pollution in India. Ozone depletion: Thinning of the stratospheric ozone layer is known as ozone •• Traffic Emissions Standards: The depletion. Such depletion causes the ‘ozone Government has decided to enforce Bharat hole’, resulting in poor screening of the Stage VI norms from 2020. harmful UV rays and increase in incidences of •• The Green Bench and the National Green skin cancer. Some of the common agents that Tribunal (NGT) give judicial safeguard to deplete ozone are CFCs. environmental protection. Acid rain: Acid rain is a form of precipitation Steps taken by the Central and the State that contains acidic components, such as governments in India: sulfuric acid or nitric acid. It damages trees, •• Road traffic rationing, encourage public crops and harms marine animals (coral reefs) transport, carpooling. and induces corrosion.

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TN_GOVT_XII_Zoology_chapter13.indd 238 25-02-2019 18:46:33 •• Increase green cover alongside roads 13.3 Water Pollution (planting avenue trees). 13.3.1 Quality of Water •• Promoting Swachh Bharat Abhiyan Water is essential for life and for the health of •• Enactment and Enforcement of stricter the environment. As a valuable natural resource, environmental laws it comprises marine, estuarine, freshwater (river •• Maintenance of air standards by proper and lakes) and groundwater environments that enforcement and monitoring stretch across coastal and inland areas. Water has two dimensions that are closely linked: quantity Average human and quality. Water quality is commonly defined consumption of Oxygen by its physical, chemical, biological and aesthetic per day = 550 L (appearance and smell) characteristics. A Cost of 2.75 L Oxygen healthy environment is one in which the water cylinder = ₹ 6500 quality supports a rich and varied community of Cost of 550 L of oxygen from tree organisms and protects public health. = ₹ 13,00,000 13.3.2 Water Pollution ------Water pollution occurs when there is a Oxygen production by one healthy change in the chemical, physical or biological tree per year =1,00,375 L quality of water that has harmful effect(s) on Cost of 2.75 L oxygen cylinder living organisms that consume it or live in it. = ₹ 6500 Water pollution adversely affects water Cost of 1,00,375 L of oxygen from one bodies due to the large amounts of natural tree /year = ₹ 23,72,50,000 or man-made materials let into it. When it becomes unfit for its intended use, water is •• Reducing carbon emissions considered polluted. •• Encourage use of renewable energy 13.3.3 Sources of Water Pollution •• Limiting the sale of firecrackers and developing eco-friendly crackers Even though water bodies or sources can be polluted by natural causes, water pollution is •• Make Environmental Impact Assessment usually caused by human activities. There are mandatory three main types of sources: point sources, Air Quality Index (AQI) is a number used non-point sources, leaks and spills. by government agencies to communicate to the Point sources: Discharge of pollutants at public how polluted the air is at a given time. specific locations through pipelines or sewers Air Quality Index into the water body. Factory effluents, sewage, AQI Air Pollution Level Colour underground mines, oil wells, oil tankers and agriculture are common point sources 0-50 Good (Fig. 13.2 a). 51-100 Moderate Non-point sources: Sources that cannot be 101-150 Unhealthy for Sensitive Groups traced to a single site of discharge like acid 151-200 Unhealthy rain, dumping of the plastics in water bodies, 201-300 Very Unhealthy agriculture chemical run off are common 301+ Hazardous examples (Fig. 13.2 b).

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TN_GOVT_XII_Zoology_chapter13.indd 239 25-02-2019 18:46:33 (a) containing waste water, sometimes in toxic concentrations. These discharges can affect temperatures of the water bodies as well as dissolved oxygen level. 3. Agricultural wastes include fertiliser and pesticide runoff from agricultural fields, food processing waste, tree and saw dust (b) from logging operations and bacteria from sewage or livestock operations. Water pollutants reach water bodies like rivers, streams and the marine system by precipitation, run-off and the groundwater by seepage or percolation.

13.3.4 Effect of Water pollution on (c) Ecosystems 1. Destruction of ecosystems: Ecosystems, especially aquatic systems, can be severely affected or destroyed by water pollution.Water pollutants affect existing niches and habitats and the survival of organisms. Soil fertility is affected and the system becomes uninhabitable. Fig 13.2 Sources of water pollution 2. Disruption of food-chains: Water Leaks and Spills: This occurs mostly due to pollution disrupts the natural food chains ship collision, off shore oil rigs, oil leakages as well as food webs. Pollutants such as and discharges into sea (Fig. 13.2 c). lead and cadmium are taken up by primary Sources of water pollution can also be classified consumers where they can be lethal or in three ways. They are municipal wastes, get stored. Later, when these animals are industrial wastes, and agricultural wastes. consumed by secondary consumers, the food chain can get disrupted at any trophic Sources of water pollution level or result in enhanced concentration of these pollutants (biomagnification). Hot water from industries when released Municipal Industrial Agricultural into the water bodies affects aquatic wastes wastes wastes density and diversity. 13.3.5. Effect of Water pollution on 1. Municipal waste water is from homes and Organisms commercial establishments. 1. Water pollution can be lethal to aquatic 2. Industrial discharge (effluents) may organisms and others that depend on contain varieties of compounds such these water bodies. as heavy metals (cadmium, chromium, Accidental oil spills from tanker ships can lead), and organic / inorganic chemicals cause substantial environmental damage. Oil

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TN_GOVT_XII_Zoology_chapter13.indd 240 25-02-2019 18:46:33 spreads on the water surface, prevents the 13.3.6 Control Measures entry of light and oxygen into the water. This 1. Right to clean water is a fundamental right increases BOD and COD, resulting in mass under the Indian Constitution. death of organisms and degradation of water 2. Water (Prevention and Control of quality. It also clogs fish gills and the feathers Pollution) Act, 1974, sections 17 to 40 of aquatic birds. prohibit the pollution of a stream or well by disposal of polluting matter. On January 28, 2017, two cargo ships collided off the Ennore coast in Chennai 3. The Central/State Pollution Control causing oil to spill into the sea. Due to wave Boards have the power to advise the action and the southern current, the spill central/state government on various spread over to 34 km down south affecting matters concerned with the prevention the coast. Beach sand also got spoiled by and control of pollution of water. the oil sludge. It took more than a thousand 4. The Ministry of Environment, Forest and volunteers to clean the oil sludge. Climate Change (MoEFCC) is the nodal agency of the Central Government for 2. Humans and other organisms can get the planning, promotion, co-ordination affected by diseases such as hepatitis and and for overseeing the implementation typhoid by consuming contaminated of India’s environmental and forestry water and food. Excess of fluoride in policies and programmes. drinking water causes fluorosis. In many poor nations, outbreak of water borne Prevention diseases and epidemics are a result of •• Regulate or control of pollutant(s) contaminated water and poor or absence discharge at the point of generation. of water treatment processes. •• Wastewater can be pretreated by scientific 3. Water pollution can cause eutrophication methods before discharge to municipal due to nutrient enrichment. This causes treatment sources. algal blooms which affect the quality •• Setting up of Sewage Treatment Plants of water bodies (Fig. 13.3). Red tides, if (STP) and Effluent Treatment Plants (ETP). occur, can be lethal to aquatic organisms. •• Regulate or restrict the use of synthetic fertilisers and pesticides. •• Public awareness and peoples’ involvement is essential.

Assessment by CPCB The number of polluted stretches in India’s rivers has increased to 351 from 302 (in 2006), and the number of critically polluted stretches – where water quality indicators are the poorest – has gone up Fig. 13.3 Algal bloom to 45 from 35 (Source: The Hindu, 17 September, 2018).

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TN_GOVT_XII_Zoology_chapter13.indd 241 25-02-2019 18:46:33 Case study •• Peptic ulcer, severe head ache, Namami Gange (National Mission memory loss. for Clean Ganga) Programme is an •• Marine animals are affected by noise Integrated Conservation Mission approved pollution from offshore activities and port as the ‘Flagship Programme’ of the Union activities. Government in June 2014 with a budget •• Fire crackers frighten animals. Birds are outlay of 20,000 crores to accomplish the often affected by increased air traffic. twin objectives of effective abatement of 13.4.3 Control pollution, conservation and rejuvenation of •• Planting trees in and around noise sources River Ganga. is an effective solution for noise pollution 13.4 Noise Pollution as plants are known to absorb noise and Sound that is unwanted and undesirable or bring down sound levels. can disrupts one’s quality of life is called as Noise. •• Regular servicing and tuning of When there is lot of ‘noise’ in the environment, automobile engines can effectively reduce it is termed as Noise Pollution. The intensity of noise pollution by vehicles and machinery. noise is meaured in decibels (dB). •• Workers should be provided with ear plugs and earmuffs at work sites that generate 13.4.1 Sources of Noise Pollution high noise levels. Vehicle engines, air horns, audio video •• Lubrication of machinery and regular systems, trains, low flying aircrafts, factory servicing minimizes noise levels. machines, sirens, motors, drillers and •• Regulations should be imposed to restrict crushers, compressor machines, crackers, the usage of loudspeakers in crowded explosives, modern supersonic transports are areas and public places. the common sources of noise pollution. 13.4.4 Legal Protection The threshold of pain is about 120 db. Article 48-A and Article 51-A of the World Health Organization has proposed that Constitution of India, Noise Pollution noise must be recognized as a major threat to (Regulation and Control) Rules 2000, and human well-being. This is applicable for all Tamil Nadu State Environment Policy living organisms. 2017 are some of the legal relief from noise pollution. 13.4.2 Effect of Noise Pollution According to Noise Pollution (Regulation •• According to the USEPA (United States and Control) Rules, 2000, the permissible Environmental Protection Agency) there limit of noise in areas categorized as are direct links between noise and health. commercial is 65 decibels (dB) during day Heart disease, high blood pressure, stress and 55 dB during night. related illness, sleep disruption, hearing 13.5 Agrochemicals loss (deafness), and productivity loss are the problems related to noise pollution. Chemicals which are used in agriculture for growth of plants and pest control are called •• Increased stress and tension, nervousness, agrochemicals or agrichemicals. irritability, anxiety, depression and panic attacks.

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TN_GOVT_XII_Zoology_chapter13.indd 242 25-02-2019 18:46:33 Overuse of agrochemicals have been observed to generate residues that cause nutrient 13.6 Biomagnification imbalance, and Food chains are components of all •• May kill beneficial bacteria and soil ecosystems. Producers and consumers form organisms. trophic levels in a chain through which energy •• Can cause eutrophication in water bodies. flow is carried out by the process of eating and being eaten. Usage, storage and transformation •• Affect aquatic animals and their of food and biomolecules by metabolism are a productivity. normal process. Degradation or breakdown is •• Pesticide containing water, even in trace an essential part of any food chain and hence all quantities is unfit for human consumption. naturally occurring substances are degradable. •• Particles (aerosols) and residues of these chemicals cause air pollution. Biomagnification of DDT •• Inhalation of contaminated air can cause When non-degradable substances enter the food respiratory problems. chain, they do not get metabolized or broken •• Consumption can lead to poisoning, side down or expelled and instead get transferred up effects and after effects. the tropic levels of the food chain. During this •• Chemicals can cause skin rashes and process, they show an increase in concentration irritation of eyes. which is referred to as biomagnification. This •• Many of these chemicals are reported to results in increased toxicity and may even be be carcinogenic. lethal. This phenomenon is well established for mercury and DDT. Figure 13.4 schematically •• They can trigger hormonal disorders and shows biomagnification of DDT in an aquatic neurotoxicity. food chain where the concentration of DDT is •• Beneficial insects and animals can be enhanced at successive trophic levels. affected. Magnification of 1. M osquito Repellents DDT concentration DEET (n-n-diethylnetatoluamide) Fish-eating and allethrin used in mosquito coils birds 10,000,000 may cause itching, burning, tingling

sensation or numbness. Large fish 1,000,000 2. Colony collapse syndrome in Honey bees due to pesticides/herbicides can Small 100,000 lead to destruction of hives and lower fish agricultural productivity. !!Remember bees are Nature’s best pollinators!! Zooplankton 10,000

Producer 1000 (Phytoplankton)

1 Water 1

Fig. 13.4 Biomagnification

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TN_GOVT_XII_Zoology_chapter13.indd 243 25-02-2019 18:46:34 13.7 Eutrophication animal wastes. Realizing the importance of When run-off from land clean potable water, the Government passed the containing nutrients reaches Water (Prevention and Control of Pollution) water bodies like lakes, it Act in 1974, which made it mandatory to treat results in dense growth of wastewater in treatment plants. The treatment plant life. This phenomenon can be carried out by three ways: is called Eutrophication. 1. Physical methods Natural aging of lakes also 2. Chemical methods leads to nutrient enrichment of its water. In a 3. Biological methods lake, the water is cold and clear (oligotrophic 1. Physical methods of wastewater stage), supporting little life. With time, streams draining into the lake introduce nutrients such treatment as nitrates and phosphates, which encourage Wastewaters containing insoluble the growth of aquatic organisms. Aquatic substances or colloids are treated through plants and animal life grow rapidly, and organic processes such as flotation, sedimentation, remains begin to be deposited on the lake filtration and centrifugal separation. bottom (mesotrophic stage) (Fig. 13.5). 2. Chemical methods of Wastewater Pollutants from anthropogenic activities treatment like effluents from the industries and homes Chemical methods of wastewater treatment can radically accelerate the aging process. include: This phenomenon is known asCultural or •• Generation of insoluble solids. Accelerated Eutrophication. •• Produce an insoluble gas. Nutrients stimulate the growth of algae, water •• Produce biologically degradable substances hyacinth and can cause clogging of canals, rivers from a non-biodegradable substance. and lakes as well as, displacing native plants. It •• Oxidize or reduce to produce a non- causes unsightly foam and unpleasant odours, objectionable substance. and deprives the water of dissolved oxygen. 3. Biological methods of Wastewater 13.7.1 Integrated Wastewater treatment Management (1) Bioremediation of wastewater includes Wastewater Treatment the aerobic treatment (oxidation ponds, aeration lagoons) and anaerobic treatment Wastewater or sewage originates from (anaerobic bioreactors, anaerobic domestic waste waters, industrial wastes and lagoons).

Fig. 13.5 Stages of Eutrophication

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TN_GOVT_XII_Zoology_chapter13.indd 244 25-02-2019 18:46:34 (2) Phytoremediation of wastewater includes constructed wetlands, Root Zone Wastewater Treatment (RZWT), and Decentralized Waste Water Treatment System (DEWATS) (Fig. 13.6 a).

G. Nammalvar was a supporter and expert of organic farming. He was an agricultural scientist, environmental activist celebrated for his work on spreading Ecological farming & Organic farming. He was against the use of chemical fertilisers and pesticides. He trained hundreds of farmers in natural farming. Nammalvar was the Fig .13.6 (a) DEWATS system at Auroville author of several Tamil and English books on natural farming, pesticides & fertilisers and was featured in magazines & television programs. He founded the Nammalvar Ecological Foundation for Farm Research and Global Food Security Trust or simply Vaanagam at Karur, Tamilnadu. He developed social forest at Ammankurai and the Kolunji Ecological Farm in Pudukottai. He and his friends made a 10-acre barren land (b) RZWT system at Aravind Eye Hospital into fertile cultivable land in the dry Pudukottai Case Study: Auroville, located in South India district. He planted 52 varieties of trees in near Puducherry has been experimenting the same waste land extending in 20 acres. with natural wastewater recycling systems His organization ‘Kudumbam’ preserves and (Fig:13.6a). Such treatment plants have regenerates hundreds of native flora and fauna, in order to ensure a sustainable livelihood. now also been implemented in Aravind Eye Hospital, Puducherry (Fig.13.6 b) and the 13.9 Solid Waste Management Chennai Mathematical Institute, Siruseri IT Every day, tonnes of solid wastes are disposed Park, Chennai. off at landfill sites. This waste comes from 13.8 Organic Farming and Its homes, offices, industries and various other Implementation agricultural related activities. These landfill It is a method of farming system which sites produce foul smell if waste is not stored primarily aims at cultivating the land and raising and treated properly. When hazardous wastes crops in such a way, so as to keep the soil alive and like pesticides, batteries containing lead, in good health by use of organic wastes (crop, cadmium, mercury or zinc, cleaning solvents, animal and farm wastes, aquatic wastes) and radioactive materials, e-waste and plastics are other biological materials along with beneficial mixed up with paper and other scraps and microbes (biofertilizers) to release nutrients to burnt, they produce gases such as dioxins. crops for increased sustainable production in These gases are toxic and carcinogenic. These an eco-friendly pollution free environment. pollute the surrounding air, ground water and can seriously affect the health of humans,

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TN_GOVT_XII_Zoology_chapter13.indd 245 25-02-2019 18:46:34 wildlife and our environment. The following Solid Waste management includes the are major sources of solid waste (Table 13.1). activities and actions required to manage waste from its inception to its final disposal. This includes the collection, transport, treatment and disposal of waste, together with monitoring and regulation of the waste management process. It is all about how solid waste can be changed and used as a valuable resource. Case Study: The Corporation of Chennai Dr. Sultan Ahmed Ismail is an Indian soil looks after clearance and management of solid biologist and ecologist from Tamil Nadu. His work has centered on techniques waste in Chennai. Every day around 5400 for recycling biodegradable waste into Metric Tonnes (MT) of garbage is collected fertiliser using varieties of earthworms, from the city. Door to door collection of garbage and on soil bioremediation. is done in most zones apart from sweeping, Dr. Ismail received a D.Sc. in Zoology collecting, and storing the waste in the specified from the University of Madras for his bins. At present garbage generated in Chennai research on the role of earthworms in is dumped at two sites. Proposals are there for soil ecology and waste management. remediation of the existing landfill or scientific He works on vermicomposting as a closure and to have integrated waste processing sustainable ecological practice. He has facilities with waste to energy plants as one of been instrumental in introducing as well the components at the existing Kodungaiyur as spreading awareness on environmental and Perungudi sites. issues, solid waste management, vermicomposting, organic farming, 13.9.1 Waste management practices vermitech and waste management to a) Source segregation several educational institutions, industries b) Composting and organic farmers in India and abroad. 1. Aerobic 2. Anaerobic

Table 13.1 Major sources of solid waste Waste category Source Food wastes, plastics, paper, glass, leather, cardboard, metals, yard wastes, Residential ashes, tires, batteries, old mattresses Industrial Packaging wastes, ashes, chemicals, cans, plastics, metal parts Thin and thick plastics, food wastes, metals, paper, glass, wood, Commercial cardboard materials Institutional Wood, paper, metals, cardboard materials, electronics Construction Steel materials, concrete, wood, plastics, rubber, copper wires, dirt and glass. and Demolition Agriculture Agricultural wastes, spoiled food, pesticide containers Syringes, bandages, used gloves, catheter, urine bags, drugs, paper, Biomedical plastics, food wastes, sanitary napkins and diapers, chemicals. Electronic items like used TVs, transistors, tape recorders, computer cabinets, E-Waste mother boards, CDs, cassettes, mouse, wires, cords, switches., chargers.

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TN_GOVT_XII_Zoology_chapter13.indd 246 25-02-2019 18:46:34 c) Vermicomposting objective of treatment activities for longer- d) Biogas generation lived radioactivity. The waste is contained e) Incineration in corrosion resistant containers and transported to disposal sites. Leaching of 13.9.2 Radioactive waste heavy metals and radionuclides from these Radioactive wastes are generated during sites is a problem of growing concern. various operations of the nuclear power plant. Radioactive waste can be in gas, liquid or solid Control and Management form, and its level of radioactivity can vary. The Three ways are employed to manage nuclear waste can remain radioactive for a few hours or wastes several months or even hundreds of thousands •• Spent Fuel Pools - The spent fuel of years. Depending on the level and nature of discharged from the reactors is temporarily radioactivity, radioactive wastes can be classified stored in the reactor pool. The Spent fuel as exempt waste, Low and Intermediate level rods are used in stored cooling ponds. waste and High Level Waste. They protect the surroundings from radiation and absorb the heat generated Radioactive waste management during radioactive decay. Radioactive waste management involves •• Vitrification method – This prevents the treatment, storage, and disposal of liquid, reaction or degradation of nuclear waste airborne, and solid effluents from the nuclear for extended periods of time and encased industry. in dry cement caskets. •• Geological Repositories - A deep The Three Mile Island geological repository is a nuclear waste (Pennsylvania, United repository excavated deep within a States), Chernobyl stable geologic environment. It is suited (Pripyat, Ukraine) and to provide a high level of long-term Fukushima Daiichi isolation and containment without future (Ōkuma, Japan) are nuclear disasters maintenance. In India at Tarapur and the world has seen in the recent period. Kalpakkam, a wet storage facility of Spent Fuel is the main mode of storage. Methods of disposal of radioactive wastes are 13.9.3 Medical waste 1. Limit generation - Limiting the generation Any kind of waste that contains infectious of waste is the first and most important material generated by hospitals, laboratories, consideration in managing radioactive wastes. medical research centers, Pharmaceutical 2. Dilute and disperse - For wastes having low companies and Veterinary clinics are called radioactivity, dilution and dispersion are medical wastes. adopted. Medical wastes contain body fluids like blood, 3. Delay and decay - Delay and decay is urine, body parts and other contaminants, frequently an important strategy because culture dishes, glasswares, bandages, gloves, much of the radioactivity in nuclear discarded needles, scalpels, swabs and tissues. reactors and accelerators is very short lived. Management: The safe and sustainable 4. Concentrate and confine process - management of biomedical waste is the social Concentrating and containing is the

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TN_GOVT_XII_Zoology_chapter13.indd 247 25-02-2019 18:46:34 and legal responsibilities of people working in can lead to adverse human health effects and healthcare centers. environmental pollution. Waste disposal: Involved by incineration, Recycling and disposal of e-waste may chemical disinfection, autoclaving, encapsulation, involve significant risk to the health of workers microwave irradiation are methods of waste and communities in developed countries disposals. Final disposal includes landfill and and great care must be taken to avoid unsafe burying as per norms inside premises. exposure in recycling operations and leaking 13.9.4 E-Waste of materials such as heavy metals from landfills Electronic waste or e-waste describes and incinerator ashes. discarded electrical electronic devices as well 13.9.5 Plastic Waste – Solutions and as any refuse created by discarded electronic Remedies devices and components and substances Plastics are low molecular weight organic involved in their manufacture or use. Their polymers that are non-degradable in the natural disposal is a growing problem because electronic environment. They are used in several items, equipment frequently contains hazardous including cars, bulletproof vests, toys, hospital substances. In a personal computer, for example, equipment, carry bags and food containers. there may be lead (Pb) in the cathode ray tube Packaging materials used in supermarkets, retail (CRT) and soldering compound, mercury outlets, manufacturing industries, households, (Hg) in switches and housing, and cobalt (Co) hotels, hospitals, restaurants and transport in steel components, among other equally companies are major contributors to plastic toxic substances. E-wastes are basically PCB waste generation. Plastic waste constitutes a (Polychlorinated biphenyl) based, which are non-degradable (Fig.13.7). major part of municipal solid waste.

• Remedies: ‘4R’- Refuse, Reduce, Reuse and Recycle mantra is the best available remedy for plastic waste pollution. • Tamil Nadu State government successfully implemented the ban on single use plastics from 1st January 2019.

13.10 Global Environment Change Green House Effect and Global warming Natural environment and climate are dynamic and keep changing over course of time. But with human population growth, industrialization and associated anthropological activities the changes are more pronounced and impactful Fig.13.7 Types of E-wastes in a much shorter time span, thus resulting in drastic Global environmental change. Used electronics which are destined for Large-scale changes of global environment can reuse, resale, salvage, recycling, or disposal lead to hazards, which may include climate are also considered e-waste. Unauthorised change, stratospheric ozone depletion, changes processing of e-waste in developing countries

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TN_GOVT_XII_Zoology_chapter13.indd 248 25-02-2019 18:46:34 in ecosystems due to loss of biodiversity, changes precipitation patterns could be affected. in hydrological systems and the supplies of Extreme wet and dry conditions can be freshwater, land degradation, urbanization, and expected (flooding and desertification). stress on food-producing systems. Coastal areas shall become more vulnerable Greenhouse gases (GHG) water vapour, to storm surges as sea level rises. Plant and carbon dioxide, methane, nitrous oxide, animal species will migrate or disappear in ozone and some artificial chemicals such as response to climate change. chlorofluorocarbons (CFCs) causes greenhouse •• Global warming can directly affect the effect. The absorbed energy warms the flora and fauna. This could also result in atmosphere and the surface of the Earth. shortage of food and even lead to food crisis; and affect the health of the people Major International Environmental and organisms. Conventions 1972: UN conference on Human Climate change threatens Nilgiri Tahr: environment, Stockholm, Sweden The endangered wild goat could lose 1972: UN environment programme approximately 60 % of its habitat, starting (UNEP), Stockholm, Sweden from the 2030s. (The Hindu, 12.08.2018) 1987: Montreal Protocol, Vienna 1989: Intergovernmental panel on climate The UNO has several measures to control change, Geneva, Switzerland. or reduce pollution. Through various 1992: Earth summit, Rio de Janeiro. conventions organized by UNO, the countries Agenda 21, otherwise called Rio assured to take steps to control or reduce conference, Brazil emissions by factories and automobiles. 1997: Kyoto Protocol, Japan 2002: World Summit on Sustainable 13.11. Impact on Specific Development, Johannesburg, South Ecosystems Africa 13.11.1 Marine Ecosystem 2003: World climate change conference, The marine ecosystem (Fig. 13.8) is the source Moscow, Russia of fish, see weeds and other marine products. 2012: UN Conference on Sustainable Development, Rio de Janeiro With the advent of intensive fishing by using 2015: UN Sustainable Development giant nets and mechanized boats, fish catch Summit, New York has dropped significantly. 2016: Montreal Protocol amendment at Kigali, Rwanda 2017: The COP23 climate change summit in Bonn, Germany 2018: UN climate change conference, Katowice, Poland

•• The large-scale global warming will have significant impact on people and nature. Fig. 13.8: Marine ecosystem As global average temperatures rise,

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TN_GOVT_XII_Zoology_chapter13.indd 249 25-02-2019 18:46:34 13.12 Ozone Depletion can result from free radicals and reactive At about 15 and 30 kilometers from the oxygen and photons can damage the DNA ground level, the earth’s atmosphere has a itself. thin layer of ozone, which absorbs ultraviolet Control: Ozone layer depletion can be sunlight. Ozone is found in the layer of the controlled by atmosphere called the Stratosphere. It acts as (1) Phase down or ban the use of CFCs a protective covering that absorbs ultraviolet (CFC free refrigerants). (UV) radiation from the sun. The ozone (2) Minimizing the use of chemicals such as molecule (O3) consists of three oxygen atoms. halons and halocarbons. It is formed when atmospheric oxygen (O ) 2 (3) Creating awareness about ozone on exposure to solar radiation breaks into two depleting agents. oxygen atoms; each atom then joins up with a single oxygen atom. The ozone molecule is Ozone hole (in purple colour), is the area unstable. It soon decays again to form molecular above Antarctica, where the ozone layer is oxygen. This cycle is a continuous process in the thinnest. the upper reaches of the stratosphere.

World Ozone Day September 16 has been designated by the United Nations as the International Day for the Preservation of the Ozone Layer. The ozone layer was discovered in 1913 by the French physicists Charles Fabry and Henri Buisson.

Causes and effects of ozone layer depletion Ozone depletion around Polar region Causes: Ozone layer depletion mainly occurs Ozone thickness is given in Dobson unit by anthropogenic actions. (see carefully the scale shown in colour from The excessive release of chlorine and violet to red). The ozone hole over Antarctica bromine from man-made compounds such as develops each year between late August and chlorofluorocarbons (CFCs) causes ozone layer early October. depletion. CFCs, methyl chloroform, carbon Courtesy: NASA tetrachloride, hydrochlorofluorocarbons, hydrobromofluorocarbons and methylbromide are found to have direct impact on the depletion 13.13 Deforestation of the ozone layer. These are categorized as Deforestation is the destruction of forests ozone-depleting substances (ODS). in order to clear the land and make it Effects: UV rays may penetrate deep into the available for other uses. Forests cover about skin and can lead to premature skin aging and 30 percent of the world’s landmass. But due wrinkling of skin; suppression of the immune to deforestation it is estimated that the earth system, skin cancer (melanoma) and chronic loses 18.7 million acres of forests per year. In effects leading to eye damage. DNA damage 2016, global tree cover loss reached a record of 29.7 million hectares.

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TN_GOVT_XII_Zoology_chapter13.indd 250 25-02-2019 18:46:34 Common methods of deforestation are burning trees and clear cutting. Amrita Devi was a brave lady from Khejarli Village of Jodhpur District, Rajasthan. 13.14 People’s Participation in She sacrificed her life to maintain Bishnoi Conservation of Forests Dharma. In 1730, Maharaja Abhay Singh, ruler of Marwar, Rajasthan state wanted to People’s participation is vital in forest log green Khejri (Prosopis cineraria) trees conservation, especially those living in them to burn lime for the construction of his new or close to the forest. This is referred to as palace. Since there was a lot of greenery in Community forestry, which varies widely in the Bishnoi villages even in the middle of legal, political and cultural settings and the Thar Desert, the king ordered his men to term covers a wide range of experiences and get the wood from Khejri trees. When she practices. came to know about the cutting of trees by the King’s men, she and many others The Bishnois, who are known conservators had hugged the Khejri trees to save from of their forest, were inspiration to many cutting. But king’s men killed Amrita Devi people’s participatory movements for along with more than 363 other Bishnois. Environmental protection in India. The It was a Tuesday, black Tuesday in Khejarli. Chipko movement resisted the destruction This incident took place to save trees and is of forests of India in the 1970s. Sunderlal recorded in India’s history. Bahuguna was the leader of this movement. People in the movement hugged the trees, and prevented felling of trees by contractors. The ‘Forest man of India’, Jadav Payeng who created 1,360 acres of dense and defiant forest was born in Arunasapori (a river island on the Brahmaputra). He had just completed his Class X exams in1979 when he started to To commemorate her bravery, the sow the seeds and shoots on the eroded island Government of Rajasthan and Madhya covered with sand and silt. Thirty-six years Pradesh have initiated the prestigious state later he had converted the once unproductive level award named as ‘Amrita Devi Bishnoi Smriti Award’ for excellent contribution to land into a forest. Payeng’s forest is now home the protection and conservation of wildlife. to five Royal Bengal tigers, over a hundred deer, wild boar, vultures, and several species of birds. For his remarkable initiative, the 13.15 Ecosan Toilets About 150 liters of wastewater at an average Jawaharlal Nehru University invited Payeng is generated by an Indian individual daily, and in 2012 on Earth Day and honoured him with a large amount of it is generated from toilets. the title of the ‘Forest Man of India’. Later, the Ecological sanitation (EcoSan) is a sustainable President APJ Abdul Kalam felicitated him system for handling human excreta by using with a cash award in Mumbai. The same year, dry composting toilets. EcoSan toilets not he received the ‘Padma Shri’. only reduce wastewater generation but also The Indian Constitution also stresses on generate the natural fertiliser from recycled human excreta, which forms an excellent the importance of the role of the People in substitute for chemical fertilisers. This protecting their environment. method is based on the principle of recovery

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TN_GOVT_XII_Zoology_chapter13.indd 251 25-02-2019 18:46:35 and recycling of nutrients from excreta to average global temperature, are deleterious to create a valuable supply for agriculture. living organisms. Increased risks of skin cancer, ‘EcoSan’ toilets are being used in several parts mutations and other disorders are potential of India and Sri Lanka. threats. Summary Earth summits, Conventions on climate change, developing of protocols and creation of Degrading natural environments, depleting emission standards and control are some of the natural resources, pollution, vulnerability to steps taken by governments towards protecting large scale environmental changes and hazards our environment and conserve for today and the are the core Environmental issues of today. future generations. Air pollution by fossil fuel burning and other anthropological activities like industrialization Evaluation is reaching alarming levels and affecting human 1. Right to Clean Water is a health and testing the survival of sensitive species. fundamental right, under Domestic and industrial sewage, and the Indian Constitution agricultural run-off are the most common reasons a) Article 12 b) Article 21 for pollution of water bodies, resulting in reduced c) Article 31 d) Article 41 dissolved oxygen and increased Biochemical Oxygen demand of water bodies. Eutrophication 2. With which of the following, the Agenda 21’ and algal blooms are regular occurrences today. of Rio Summit, 1992 is related to? Industrial wastewaters are often rich in toxic a) Sustainable development chemicals, heavy metals and organic compounds b) Combating the consequences of which harm living organisms and may even population result in death of aquatic life. c) Mitigation norms of Green House Noise pollution is a threat to human and Gases (GHGs) emission. other animals. It can affect health and disturb d) Technology transfer mechanism to peaceful habitats. Agrochemicals and its usages developing countries for ‘clean-energy’ cause many ill effects in human beings, other production. organisms and soil. Agrochemicals can also 3. Which among the following awards cause biomagnification. The solution is to revert instituted by the Government of India for to non-chemical farming (use of biofertilisers, individuals or communities from rural areas biopesticides, protect pollinators) practices. that have shown extraordinary courage and Generation of municipal wastes and their safe dedication in protecting Wildlife? disposal are major issues faced by communities a) Indira Gandhi Paryavaran Puraskar today. Solid wastes create environmental b) Medini Puruskar Yojana problems and must be disposed-off in safe ways. Disposal of solid wastes, radioactive wastes and c) Amrita Devi Bishnoi Award e-wastes requires further efforts and research. d) Pitambar Pant National Award Solid wastes like plastic can be combated by 4. The ‘thickness’ of Stratospheric Ozone layer practicing the 4R - refuse, reduce, reuse and is measured in/on: recycle. Ecosan toilets are some of the universally a) Sieverts units b) Dobson units accepted eco-friendly practices. c) Melson units d)Beaufort Scale Green house effect and depletion of ozone 5. Which among the following is the most layer are aggravated by emissions of carbon abundant Green-House-Gas (GHG) in the dioxide, methane, nitrous oxide and CFCs and earth’s atmosphere? deforestation. Melting of ice caps, rising sea levels, change in rainfall patterns, increase in a) Carbon dioxide b) Water Vapour

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TN_GOVT_XII_Zoology_chapter13.indd 252 25-02-2019 18:46:35 c) Sulphur Dioxide d) Tropospheric Ozone 14. Expand (i) CFC (ii) AQI (iii) PAN 6. As per 2017 statistics, the highest per capita 15. What is SMOG and how it is harmful for us? emitter of Carbon dioxide in the world is 16. List all the wastes that you generate, at home, a) USA b) China school or during your trips to other places. c) Qatar d) Saudi Arabia Could you very easily reduce the generation of these wastes? Which would be difficult or 7. The use of microorganism metabolism to rather impossible to reduce? remove pollutants such as oil spills in the water bodies is known as 17. Discuss the causes and effects of global warming. What measures need to be taken a) Biomagnification b) Bioremediation to control global warming? c) Biomethanation d) Bioreduction 18. What would Earth be like without the 8. The Ozone Day is observed every year on greenhouse effect? September 16 as on this day in 1987 the 19. Write notes on the following: ______was signed for launching efforts to arrest the depletion of the fragile a. Eutrophication ozone layer in the stratosphere that prevents b. Algal Bloom the harmful ultra-violet rays of the sun from 20. What effect can fertilizer runoff have on an reaching the earth. Fill the correct word in aquatic ecosystem? blank. 21. How can we control eutrophication? a) Montreal Protocol b) Geneva Protocol 22. Why does ozone hole form over Antarctica? c) Kyoto Protocol d)Nagoya Protocol 23. Mention the causes of enhanced use of 9. Which among the following always ultraviolet radiation. decreases in a Food chain across tropic 24. Discuss the role of women in protection and levels? conservation of forests. a) Number b)Accumulated chemicals 25. Discuss the role of an individual to reduce c) Energy d) Force environmental pollution. 10. In the E-waste generated by the Mobile 26. How does recycling help reduce pollution? Phones, which among the following metal 27. What is the primary purpose of the Kyoto is most abundant? Protocol? a) Copper b) Silver 28. In what way Peyang conserves the forest? c) Palladium d) Gold 29. Discuss briefly the following : 11. The Hydrochlorofluorocarbons (HCFCs) a. Catalytic converter are the compounds which have the b. Greenhouse gases following molecules: c. Ecosan a) Hydrogen b) Carbon 30. What are some solutions to toxic dumping c)Chlorine d)Fluorine in our oceans? 12. SMOG is derived from : 31. Describe how deforestation might a) Smoke b) Fog contribute to global warming. c) Both A and B d) Only A 32. How does forest conservation help to reduce 13. Excess of fluoride in drinking water air pollution? causes: a) Lung disease b) Intestinal infection c) Fluorosis d) None of the above

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TN_GOVT_XII_Zoology_chapter13.indd 253 25-02-2019 18:46:35 Glossary Canopy – The canopy is the above ground portion of a plant community or crop, formed Abiogenesis – The emergence by the collection of individual plant crowns. of life forms emerging from non-living chemical systems. Carcinogens– Substance causing cancer In contrast with spontaneous Cardiac arrhythmia– Any variation from the generation, abiogenesis is not normal rhythm in the heartbeat. a process that biologists think continues in a particular environment, such as a planet or moon, Carrier – An individual heterozygous for a once a living system has emerged. recessive gene that is not expressed

Acidogenesis – Conversion of simple organic Catastrophic– Something or substance that materials into acetate, H2 and CO2 by acidogenic involves or causes a sudden terrible disaster. bacteria. Changes in animals over time in response to Algal bloom – Presence of large amounts of changing environmental factors /conditions. nutrients in waste water causing excessive growth Adaptations help develop physiological, behavioral of planktonic algae. and structural / functional traits which increase the chances of survival of the organisms. Allergy - A hypersensitivity reaction that can involve various deleterious effects. Chemical oxygen demand - A measure of the oxygen required to oxidize soluble and particulate Anthropogenic causes– Problems created organic matter in water. by human Cirrhosis - Scarring of the liver that impairs its Anthropology – The study of differences and functioning. similarities, both biological and cultural, in human populations. Anthropology is concerned with Co-dominance – In a heterozygote, the dominant typical biological and cultural characteristics of and recessive allele is capable of phenotypic human populations in all periods and in all parts expression. of the world. Coacervates – are the microscopic spontaneously Antisense DNA– It is the non coding strand formed spherical aggregates of lipid molecules complementary to the coding strand in double that are held together by electrostatic forces and stranded DNA. The antisense strand serves as a that may have been precursor of cells. They are template for mRNA synthesis. the cluster of molecular aggregates in colloidal form which are bounded by a membrane Apoptosis– Is a form of programmed cell death and grows by absorbing molecules from the that occurs in multicellular organisms. environment. Oparin believed that life developed Attenuated – reduced in virulence. from coacervates.

Autoradiography – It is the use of X-ray or Cytolysis - Destruction of cells photographic film to detect radioactive materials. Cursorial – A cursorial organism is one Bacteriophages– Viruses which infect bacterial that is adapted specifically to run. Cursorial cells. organisms are typically adapted to long- distance running at high speeds, rather than Biogeography - The scientific study of the animals with high acceleration over short geographic distribution of organisms.

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TN_GOVT_XII_Glossary.indd 254 25-02-2019 18:48:41 distances; thus, a cheetah is considered Euchromatin – Euchromatin is a tightly packed cursorial, while a leopard is not. form of chromatin that is enriched in genes, and is often under active transcription. Denaturing – Denaturing means separation or splitting of the double helix into single stands Eutrophication - Excessive richness of nutrients by breaking hydrogen bonds between the two in a lake or other water bodies frequently due to strands. run of fertilizers from the land causing dense growth of plant life. Dendritic cells - Professional antigen presenting cells that have long membrane processes Fibroids – Fibroids are abnormal growths formed on the outside, inside or in the walls of Diapedesis - The movement of blood cells the uterus. (leucocytes) out of the circulatory system and towards the site of tissue damage or infection Foetus – Developmental stage extending accompanying inflammation. from the ninth week of development to birth. Dinosaurs - a term coined by Sir Richard Owen for giant extinct reptiles. Group of animals that Fossorial – Fossorial (from Latin fossor, have bird-like and lizard-like facial appearance meaning "digger") is an animal adapted (Mesozoic). to digging which lives primarily, but not solely, underground. Some examples are Distribution – The occurrence of different badgers, naked mole-rats, clams, and mole organisms in a given area and the way they are salamanders. distributed in their space, specific time and utilization of their resources. ]Galaxy – a specific arrangement of stars.

DO – Dissolved Oxygen is the amount of Gene bank-A facility established for the ex-situ gaseous oxygen (O2) dissolved in the water. Conservation of individuals, seeds, tissues or reproductive cells . Ecotourism - Travel undertaken to witness sites or regions of unique natural ecological quality Gene pool – the total gene content of a whole the provision of services to facilitate such travel. species.

El Nino– Unusual warming of surface waters in Genetic drift – an alteration in the gene the eastern tropical Pacific Ocean. frequency.

Emphysema– A serious medical condition that Geology – the study of origin and structure of occurs when the lungs become larger and do not Earth. work properly, causing difficulty in breathing. Glaciers– A large mass of ice that moves slowly. Endemism-The phenomenon in which the Group of individuals of the same species living organisms are exclusively restricted to a given in a given area at a given time and reproduce area. among themselves. Endometriosis – An abnormal condition in Haemophilia – A medical condition in which which endometrial tissue that normally lines the ability of the blood to clot is severely the uterus grows outside . reduced, causing the patient to bleed severely Eohippus – ancestor of modern horse. from even a slight injury.

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TN_GOVT_XII_Glossary.indd 255 25-02-2019 18:48:41 Haemozoin - Toxic malarial pigment that average change in other species population or causes malaria fever. ecosystem process.

Hallucination - The sensation of seeing, hearing Locus – The particular point on the chromosome or sensing something that does not exist. at which the gene for a given trait occurs.

Heterochromatin – Heterochromatin is a Macrophage - A large, leucocyte derived from a tightly packed form of DNA or condensed monocyte that functions in phagocytosis, DNA. Malt - Mucosal Associated Lymphoid Tissue Homeostasis– It is the state of steady internal collective terms for secondary lymphoid organs conditions maintained by living things. located along various mucous membrane surfaces including Peyer’s patches, tonsils, Immune reaction – The production of appendix antibodies in response to antigens Mast cell - A bone marrow derived cell Interferon - An antiviral protein produced from virally infected fibroblasts and leucocytes Menarche – Starting of the first menstrual induces antiviral state in uninfected cells. period.

Intersex – An individual showing a combination Merozoite - A trophozoite of Plasmodium of male and female characteres. found in RBC or liver cells.

Intra-Uterine Insemination (IUI)-Processed Methanogenesis – Conversion of acetate, H2 sperm sample is infused into the uterus, by and CO2 into methane by methane producing passing the vagina. Intracytoplasmic sperm bacteria injection (ICSI)-injection of a sperm directly Molecular biology – The branch of biology into the ovum. which attempts to interpret biological events Intra uterine transfer (IUT)-Transfer of in terms of the physico chemical properties of embryo with more than 8 celled blastomeres molecules in a cell. into the uterus. Molecular pharming – Production of active pharmaceutical substances in genetically In vitro fertilization (IVF)- Fertilization moldified organisms outside the body in the laboratory. Mould – an impression of a complete organism In vivo fertilization -fusion of gametes within or a part of it in the rock that surrounds it. the female Multple sclerosis– is a demyelinating disease in Inflammation -e.g., Vaginitis- inflammation which the insulating covers of nerve cells in the in the vagina, urethritis- inflammation in the brain and spinal cord are damaged. urethra,endocervicitis- inflammation inside the cervix, epididymitis - inflammation in the Mutation – sudden and inheritable changes. epididymis, prostatitis - inflammation in the Narcotic - A powerful drug that produced, prostate gland relaxed, dreamy state, derived from Opium Keystone species-A species whose loss from plant. an ecosystem would cause a greater than

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TN_GOVT_XII_Glossary.indd 256 25-02-2019 18:48:41 Nascent RNA – Nascent RNA is an immediately Planetesimals - Planetesimals are the formed RNA. In this RNA no post transcriptional fundamental building blocks of the planets as modification had occured. well as the ancestors of asteroids and comets.

NBOD – Nitrogenous BOD Polypeptide chain– It consists of smaller subunits or amino acids that are linked together. Nk cells - Natural Killer cells that kill infected They are the building blocks of proteins. and tumor cells. Postpartum – Period of life following childbirth. Nondisjunction – Nondisjunction is the failure of homologous chromosomes or sister Precursor– A substance from which another is chromatids to separate properly during cell formed, especially by metabolic reaction division Primer – A short oligonucleotide that hybridizes NPK fertilizers– Fertilizers with Nitrogen (N), the template strand and gives a 3’ – OH end for the Phosphorus (P) and Potassium (K). initiation of nucleic acid synthesis.

Nucleosome – A morphologically repeating Probe – The probe is a single stranded DNA unit of DNA containing 190 base pairs of DNA molecule that is ‘complementary’ to the gene of folded together with eight histone molecules. interest in a sample under study.

Null cell - A small population of peripheral Pseudopodia – Blunt temporary protoplasmic blood lymphocytes that lack the membrane projections found in Amoeba or in some amoeba- markers characteristic of B and T cells. Natural like cells. killer cells are included in this group. Psychoactive drug - A chemical substance that Number of individuals in a population within a acts on brain and affects the mind and behaviour defined unit of space and time. of user.

Ontogeny – life history of an individual. Puberty – Period of reproductive maturity Pyrolysis– Decomposition brought about by high Oocyte – The encysted zygote of Plasmodium temperatures. Operon – A cluster of genes whose expression Recombinant– A cell or organism whose genetic is controlled by a single operator. complement results from recombination Panspermia – units of life in the forms of spores. Redia – Larva in the life cycle ofmost trematodes. Permafrost – Any ground that remains Rheoreceptors – They are receptors in fish completely frozen (32°F (0°C) or colder) for and some amphibians that respond to water at least two years straight. These permanently currents. frozen grounds are most common in regions with high mountains and in Earth’s higher Saltation – single step large mutation. latitudes near the North and South Poles. Satellite DNA – Short highly repeated Phenotypic plasticity - the ability of one genotype eukaryotic DNA sequences, usually clustered in to produce more than one phenotype when heterochromatin and generally not transcribed exposed to different environments. Saltatorial – Saltatorial is an animal adapted to Phylogeny – recalling of ancestral history. leaping. They have large, muscular hindlimbs and sometimes, reduced forelimbs. A few example

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TN_GOVT_XII_Glossary.indd 257 25-02-2019 18:48:41 for jumpers in the animal kingdom include fleas, Transgene– The target gene responsible for the froghoppers, grasshoppers, and frogs. development of transgenic organism.

Schizogony - The process of multiple fission, in Trophozoite stage – In Plasmodium life cycle, which one organism divides to produce many cryptomerozoites in the RBC become round and it daughter cells. modifies into a young trophozoite. Schizont – The trophozoite of Plasmodium grows Umbilical cord – Structure bearing arteries and in size to form the schizont. veins connecting the placenta and the foetus. Selection – choosing the better adapted alleles Variations – dissimilarity between the members of from the mixed population. the same species. Sewage - Domestic waste water containing various Vitrification– Transformation of a substance into solid and liquid waste materials including human a glass. excreta. Volatility– A liquid or substance is one that will Single cell protein (SCP) – A protein derived from quickly change into a gas. a culture of single celled organisms used especially Withdrawal symptoms - The reactions as a food supplement. experienced by an addict after he/she stops using SOD– Sediment Oxygen Demand is the rate at drugs. which dissolved oxygen is removed from the water Woolly mammoth – A hairy relative of modern column during the decomposition of organic elephant that lived in cold climates. matter in streambed or lakebed sediments. Zoogeography – study of details with the Solubilisation – Dissolving the feed stock in water geographical distribution of animals. to make a slurry for anaerobic digestion. Zygote intra fallopian transfer-(ZIFT) Speciation – formation of new species from the transfer of zygote or embryo with 8 or pre-existing ones. less than 8 celled blastomeres into the Structural gene – A gene coding for the structure fallopian tube. of a protein. Taq DNA polymerase– is a thermostable DNA polymerase obtained from thermophilic bacterium Thermus aquaticus. It helps in the synthesis of DNA.

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• Roitt(2001). Immunology. Harcourt • Verma P.S., Agarwal V.K. Environmental Publishers limited. Sixth edition. Biology – S.Chand & Company Ltd.

• S.N.Chary Ecology – Environmental • Verma PS and Agarwal VK., (2008), Studies, First Edition 2008, Published by Genetics, Ninth Revised multicolor Rajiv Beri for Macmillan India Ltd. edition, S.Chand & Company Ltd.

• Sekar, P. & Mathivanan, J. (2008). • William J. Thieman and Michael A Environmental Education, Neminatha Palladino (2004), Introduction to Pathippagam, Polur. Biotechnology, Pearson Education Inc., and Dorling Kingsley Publishing Inc., • Sharma P.D. Ecology and Environment New Delhi, India 12th edition – 12th Revised edition, Rastogi publication.

• Silverthorn, D.U(2016). Human Physiology.An integrated approach. Pearson Education Limited. Seventh Edition.

• Stiling, P. (2012). Ecology: Global Insights & Investigations, McGraw-Hill Companies Inc., New York.

• Tamarin RH (2007), Principles of genetics, 7th edition, tata Mcgraw hill publication Ltd.

• Tamil Nadu State Environment Policy – 2017, Department of Environment, Government of Tamil Nadu, Chennai - 600 015.

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TN_GOVT_XII_ Reference.indd 261 25-02-2019 18:49:32 MCQs for Higher Studies

Chapter 1 - Reproduction in Organisms Chapter 2 - Human Reproduction 1. “Nothing lives forever, but life continues”. What 1. Select the incorrect statement. [NEET 2016, phase I] does it mean? [AIPMT 1995] a) LH and FSH trigger ovulation in ovary a) Older dies but new ones are produced by b) LH and FSH decrease gradually during the reproduction follicular phase b) Nothing can produce without death c) LH triggers secretion of androgens from the Leydig cells. c) Death has nothing to do with the continuation of d) FSH stimulates the sertoli cells which help in life spermiogenesis d) Parthenogenesis is must for sexual reproduction 2. Identify the correct statement on ‘inhibitin’ 2. A few statements describing certain features of [NEET 2016, phase I] reproduction are given below. Select the options that a) is produced by granulose cells in ovary and are true for both sexual and asexual reproduction inhibits the secretion of FSH from the options given: b) is produced by granulose cells in ovary and inhibits i. Gametic fusion takes place the secretion of LH ii. Transfer of genetic material takes place c) is produced by nurse cells in testes and inhibits the iii. Reduction division takes place secretion of LH iv. Progeny have some resemblance with parents d) inhibits the secretion of LH, FSH and prolactin. a) i and ii b) ii and iii 3. Several hormones like hCG, hPL, oestrogen and c) ii and iv d) i and ii progesterone are produced by [NEET 2016, phase I ] 3. A few statements with regard to sexual reproduction a) ovary b) placenta are given below: c) fallopian tube d) pituitary i. Sexual reproduction does not always require two 4. Match column I with column II and select the correct individuals option using the codes given below ii. Sexual reproduction generally involves gametic [NEET 2016, phase I] fusion Column I Column II iii. Meiosis never occurs during sexual reproduction A. Mons pubis 1.Embryo formation iv. External fertilization is a rule during sexual B. Antrum 2. Sperm reproduction Choose the correct statements from the options C. Trophectoderm 3. Female external genitalia below: D. Nebenkem 4. Graafian follicle a) i and iv b) i and ii A B C D c) ii and iii d) i and iv a) 3 4 2 1 4. Given below are a few statements related to external b) 3 4 1 2 fertilization. Choose the correct statements: c) 3 1 4 2 i. The male and female gametes are formed and d) 1 4 3 2 released simultaneously 5. Which one of the following is not the function of ii . Only a few gametes are released into the medium placenta? (NEET, 2013) iii. Water is the medium in a majority of organisms a) To facilitate supply of oxygen and nutrients to embryo exhibiting external fertilization b) To secrete oestrogen iv. Offspring formed as a result of external c) To facilitate the removal of carbondioxide and fertilization have better chance of survival than material from embryo those formed inside the organism d) T o secrete oxytocin during parturition a) iii and iv b) i and iii 6. The testes in human are situated outside the c) ii and iv d) i and iv abdominal cavity inside a pouch called scrotum. The 5. W hich of the following statements, support the view purpose served is for [AIPMT 2011] that elaborate sexual reproductive process develops a) escaping any possible compression by the visceral organs. much later in the organic evolution? ) b providing more space for the growth of epididymis. i) Lower groups of organisms have simpler body design  c) providing a secondary sexual feature for exhibiting ii)Asexual reproduction is common in lower groups the male sex iii)Asexual reproduction is common in higher  d) maintaining the scrotal temperature lower than groups of organisms internal body temperature iv)The high incidence of sexual reproduction is in 7. Hormones secreted by placenta to maintain angiosperms and vertebrates. pregnancy are [NEET,2018] a) i, ii and iii b) i, iii and iv a) hCG, hPL, progesterone, estrogen c) i, ii, and iv d) ii, iii and iv b) hC G, hPL, estrogen, relaxin, oxytocin

MCQs for Higher Studies 262

Competitive Questions for Higher studies NEW.indd 262 25-02-2019 18:55:28 c) hCG, hPL, progesterone, prolactin b) Out of one pair factors one is dominant and the d) hCG, progesterone, estrogen, glucocorticoids other recessive 8. Match and select the correct option [NEET, 2018] c) Alleles do not show any blending and both the Column I Column II characters recover as such in F2 generation d) Factors occur in pairs a. Proliferative phase 1. Breakdown of 3. ABO blood groups in humans are controlled by the endometrium lining gene I. It has three alleles – IA, IB and i. Since there b. Secretory phase 2. Follicular phase are three different alleles, six different genotypes are possible. How many phenotypes can occur? c. Menstruation 3. Luteal phase [AIPMT PRE 2010] a b c a) Three b) One c) Four d) Two A) 3 2 1 4. Which one of the following symbols and its B) 2 3 1 representation, used in human pedigree analysis is C) 1 3 2 correct? [AIPMT PRE 2010] D) 3 1 2 a) □ =○=Mating between relatives b) ○ =Unaffected male Chapter 3 - Reproductive Health c) □ =Unaffected female 1. Which of the following is a hormone releasing d) ◊=Male affected Intrauterine Device (IUD)? [AIPMT 2014] 5. Which one of the following conditions correctly a) Multiload 375 b) LNG-20 describes the manner of determining the sex in the c) Cervical cap d) Vault given example? [AIPMT PRE 2011] 2. Assisted reproductive technology, IVF involves the a) XO type of sex chromosomes determine male transfer of [AIPMT 2014] sex in grasshopper a) Ovum into the fallopian tube b) XO condition in humans as found in Turner b) Zygote into the fallopian tube syndrome, determines female sex c) Zygote into the uterus c) Homozygous sex chromosomes(XX) produce d) Embryo with 16 blastomeres into the fallopian tube male in Drosophila 3. In context of amniocentesis, which of the following d) Homozygous sex chromosomes(ZZ) determine statements is incorrect? [NEET-I, 2016] female sex in birds a) It is usually done when a woman is between 14-16 6. A normal-visioned man whose father was blind, weeks pregnant marries a woman whose father was also colour b) It is used for prenatal sex determination blind. They have their first child as a daughter. What c) It can be used for detection of Down syndrome are the chances that this child would be colour blind? d) It can be used for detection of Cleft palate [AIPMT PRE 2012] 4. Which of the following approach does not give the a) 100% b) 0% c) 25% d) 50% defined action of contraceptive? [NEET-I, 2016] 7. Which of the following statements is not true of two a) Barrier methods Prevent fertilization genes that show 50 per cent recombination frequency [AIPMT 2013] b) Intra uterine Increases phagocytosis of sperms, a) The genes may be on different chromosomes devices suppresses sperm motility and b) The genes are tightly linked fertilizing capacity of sperms c) The genes show independent assortment c) Hormonal Prevent retard entry of sperms, d) If the genes are present on the same chromosome contraceptives prevent ovulation and fertilization 8. A pleiotropic gene: [RE-AIPMT 2015] d) Vasectomy Prevents spermatogenesis a) Is a gene evolved during Pliocene b) Controls a trait only in combination with another gene Chapter 4 - Principle of Inheritance and Variation c) Controls multiple traits in an individual 1. The fruit fly Drosophila melanogaster was found d) Is expressed only in primitive plants to be very suitable for experimental verification of 9. A gene showing codominance has: [RE-AIPMT 2015] chromosomal theory of inheritance by Morgan and a) Alleles tightly linked on the same chromosome his colleagues because [AIPMT MAINS 2010] b) Alleles that are recessive to each other a) It reproduces parthenogenetically c) Both alleles independently expressed in the b) A single mating produces two young flies heterozygote c) Smaller female is easily recognizable from large male d) One allele dominant on the other d) It completes the life cycle in about two weeks 10. Pick out the correct statements: [NEET-I, 2016] 2. Which one of the following cannot be explained on a) Haemophilia is a sex-linked recessive disease the basis of Mendel’s Law of Dominance? b) Down’s syndrome is due to aneuploidy [AIPMT PRE 2010] c) Phenylketonuria is an autosomal recessive gene disorder a) The discrete unit controlling a particular character d) Sickle cell anaemia is an X-linked recessive gene is called a factor disorder

263 MCQs for Higher Studies

Competitive Questions for Higher studies NEW.indd 263 25-02-2019 18:55:28 a) A and D are correct b) B and D are correct c) Prove semi- conservative nature of DNA replication ) c A,C and D are correct d) A,B and C are correct d) Polymerises in the 5’ to 3’direction and explain 3’ to 5’ DNA replication Chapter 5 - Molecular Genetics 8. During translation initiation in prokaryotes, a GTP 1. The association of histone H1 with a nucleosome molecules is needed in [AIPMT 2003] indicates (NEET 2017) a) association of 30s, mRNA with formyl met tRNA a) Transcription is occurring b) association of 50s subunit of ribosome with b) DNA replication is occurring initiation complex c) The NAD is condensed into chromatin fibre c) formation of formyl met tRNA d) The DNA double helix is exposed d) binding of 30s subunit of ribosome with mRNA. 2. Which of the following is not required for any of 9. Reverse transcriptase is the techniques of DNA fingerprinting available at a) RNA dependent RNA polymerase present? [NEET 2016] b) DNA dependent RNA polymerase a) Zinc finger analysis c) DNA dependent DNA polymerase b) Restriction enzymes d) RNA dependent DNA polymerase c) DNA-DNA hybridization 10. Escherichia coli fully labeled with N14 medium. The d) polymerase chain reaction two strands of DNA molecules of the first generation 3. Satellite DNA is important because it [AIPMT 2015] bacteria have a) codes for proteins needs in cell cycle a) Different density and do not resemble parent DNA b) shows high degree of polymorphism in population b) Different density but resemble parent DNA and also the same degree of polymorphism in c) Same density and resemble parent DNA an individual, which is heritable from parents to d) Same density but do not resemble parents DNA children Chapter 6 - Evolution c) Does not code for protein and is same in all 1. The wings of a bird and of an insect are members of the population. a) homologous structure and represent convergent d) Codes for enzymes needed for DNA replication. evolution 4. The diagram shows an important concept in the b) homologous structure and represent divergent evolution genetic implication of DNA. Fill in the blanks A to C. c) analogous structure and represent convergent (NEET 2013) evolution A B C d) analogous structure and represent divergent evolution DNA ----→mRNA ------→protein -proposed by--- 2. Which one of the following statement is correct? a) A- trancscription, B- replication C-James Watson a) stem cells are specialized cells b) A- trancscription, B- trancscription, C-Erwin a) there is no evidence of the existence of gills during c) A- trancscription, B- tranlation, C-Francis Crick embryogenesis of mammals d) A- trancscription, B- extension, C-Rosalind b) all plant and animal cells are totipotent Frankin c) Ontogeny repeats phylogeny 5. Select the two statements out of the four (I –IV) given 3. In Hardy-Weinberg equation, the frequency of below about lac operon. [AIPMT 2010] heterozygous individual is represented by i. Glucose or galactose may bind with the repressor a) P2 b) 2pq q c) p d) q2 and inactive it. 4. The correct order in Era is ii. In the absence of lactose, the repressor binds a) Palaeozoic---- Archaeozoic --- Coenozoic with the operator region b) Archaeozoic ---Palaeozoic------Proterozoic iii. The z-gene codes for permease. c) Palaeozoic--- Mesozoic ----- Coenozoic iv. This was lucidatede by Francois Jacob and d) Mesozoic ---- Archaeozoic---- Proterozoic Jacques monod. 5. The most apparent change during the evolutionary The correct statements are history of Homo sapiens is raced in (AIPMT 2010) a) i and ii b) i and iii c) ii and iv d) i and ii a) loss of body hair 6. Which one of the following pairs of codons is b) walking upright correctly matched with their function or the single c) shortening of jaws for the particular amino acid? [AIPMT 2008] d) remarkable increase in the brain size. a) GUU, GCU – Alanine 6. The process by which organisms with different b) UAG, UGA – Stop codon evolutionary history evolve similar phenotypic c) AUG, ACG - start/methionine adaptations in response to a common environmental d) UUA, UCA – Leucine challenge is called (AIPMT 2013) 7. The Okazaki fragments in DNA chain growth a) Natural selection (AIPMT 2007) b) Convergent evolution a) Result in transcription c) Non-random evolution b) Polymerise in the 3’ to 5’ direction and forms d) Adaptive radiation Human health and diseases replication fork

MCQs for Higher Studies 264

Competitive Questions for Higher studies NEW.indd 264 25-02-2019 18:55:28 Chapter 7 & 8 - Human Health and Diseases and Immunology a) Ancylostoma duodenale 1. Select the correct statement from the given below. b) Enterobius vermicularis [AIPMT 2010] c) Trichimella spiralis a) Barbiturates when given to criminals make them d) Ascaris lumbricoides tell the truth 8. The active form ofEntamoeba histolytica feeds upon: b) Morphine is often given to persons who have [AIPMT 2015] under gone surgery as a pain killer a) Erythrocytes, mucosa and submucosa of colon c) Chewing tobacco lowers blood pressure and heart rate b) Mucosa and submucosa colon only d) Cocaine is given to patients after surgery as it c) Food in intestine stimulates recovery d) Blood only 2. Match the following [AIPMT 2008] 9. Which one of the following statements is correct with Column I Column II respect to AIDS? [AIPMT PRE 2010] a) The HIV can be transmitted through eating food A) Amoebiasis i) Treptonema pallidum together with an infected person. B) Diphtheria ii) Use only sterilized food b) Drug addicts are least susceptible to HIV infection. and water c) AIDS patients are being fully cured 100 percent C) Cholera iii) DPT vaccine with proper care and nutrition. D) Syphilis iv) Use oral rehydration d) The causative HIV retrovirus enters helper therapy T-lymphocytes thus reducing their numbers. A B C D 10. Select the correct statement with respect to diseases a) i ii iii iv and immunization [AIPMT MAINS 2011] b) ii iv i iii a) If due to some reason B and T lymphocytes are c) ii I iii iv damaged, the body will not produce antibodies d) ii iii iv i against a pathogen 3. If a person shows production of interferons in his b)Injection of dead/inactivated pathogens caused body, the chances are that he has got an infection of passive immunity a) Typhoid b) Measles c) Certain protozoans have been used in mass c) Tetanus d) Malaria production of hepatitis B vaccine. 4. A person suffering from a disease caused by d) Injection of snake antivenom against snake bite is Plasmodium, experiences recurring chill and fever at an example of active immunization. the time when? [AIPMT MAINS 2010] 11. Which one of the following statements is correct with a) The sporozoites released from RBC’s are being respect to immunity? [AIPMT MAINS 2012] rapidly killed and broken down inside spleen a) The antibodies against small pox pathogen are b) The trophozoites reach maximum growth and give produced by T – lymphocytes out certain toxins. b) Antibodies are protein molecules each of which c) The parasite after its rapid multiplication inside has four light chains. RBC’s reptures them, releasing the stage to enter c) Rejection of a kidney graft is the function of B – fresh RBC’s lymphocytes. d) The microgametocytes and megagametocytes are d) Preformed antibodies need to be injected to being destroyed by the WBC’s treat the bite by a viper snake. 5. Where will you look for the sporozoites of the 12. Which one of the following is not a property of material parasite? [AIPMT PRE 2011] cancerous cells whereas the remaining three are? a) Red blood corpuscles of humans suffering from malaria. [AIPMT PRE 2012] b) Spleen of infected humans a) They compete with normal cells for vital nutrients c) Salivary glands of freshy moulted female anopheles b) They do not remain confined in the area of formation mosquito. c) They divide in an uncontrolled manner d) Saliva of infected female anopheles mosquito. d) They show contact inhibition 6. Which one of the following organisms is scientifically 13. At which stager HIV infection does one usually show and correctly named, correctly printed according symptoms of AIDS? [AIPMT 2014] to the International Rules of Nomenclature and a) Within 15 days of sexual contact with an infected correctly described? [AIPMT MAINS 2012] person a) Plasmodium falciparum – a protozoan causing b) When the infected retro virus enters host cells the most serious type of malaria. c) When HIV damages large number of helper T- b) Felis tigris – The Indian tiger is well protected in Lymphocytes Gir forests. d) When the viral DNA is produced by reverse c) E. Coli – The full name is Entamoeba coli, a transcriptase commonly occurring bacterium in human intestine. 14. Match each disease with its correct type of vaccine 7. Which of the following endoparasites of humans [AIPMT 2015] does show vivipaity? [AIPMT 2015]

265 MCQs for Higher Studies

Competitive Questions for Higher studies NEW.indd 265 25-02-2019 18:55:28 a)Tuberculosis i) harmless virus 5. During sewage treatment, biogas are produced which includes [AIPMT 2015] b)Whooping cough ii) inactivated toxin a) Methane, hydrogen sulphide, carbon dioxide c)Diphtheria iii) killed bacteria b) Methane, oxygen, hydrogen sulphide d)Polio iv) harmless bacteria c) Hydrogen sulphide, methane, sulphur dioxide a) b) c) d) d) Hydrogen sulphide, nitrogen, methane a) (ii) (i) (iii) (iv) 6. What gases are produced in anaerobic sludge b) (iii) (ii) (iv) (i) digesters? [AIPMT 2014] c) (iv) (iii) (ii) (i) a) Methane and CO2 only d) (i) (ii) (iv) (iii) b) Methane, hydrogen sulphide and CO2 15. Which of the following is correct regarding AIDS c) Methane, hydrogen sulphide and O2 causative agent HIV? [NEET-II, 2016] d) Hydrogen sulphide and CO2 a) HIV is enveloped virus that contains two e) Consumption of organic matter in the water is identical molecules of single-stranded RNA and higher by the microbes two molecules of reverse transcriptase 7. Match the following list of microbes and their b) HIV is unenveloped retrovirus importance: [RE-AIPMT 2015] c) HIV does not escape but attacks the acquired a)Saccharomyces (i)Production of immune response cerevisiae immunosuppressive agents d HIV is enveloped virus containing one molecule of b)Monasus purpureus (ii)Ripening of Swiss cheese single – stranded RNA and one molecule of reverse c)Trichoderma (iii)Commercial transcriptase polysporum production of ethanol Chapter 9 - Microbes in Human Welfare d)Propionibacterium (iv)Production of blood- shermanii cholesterol lowering agents. 1. When domestic sewage mixes with river water e) (iv) (iii) (ii) (i) [AIPMT MAINS 2010] f) (iv) (ii) (i) (iii) a) Small animals like rat will die after drinking river water g) (iii) (i) (iv) (ii) b) The increased microbial activity releases h) (iii) (iv) (i) (ii) micronutrients such as iron. 8. Which of the following is wrongly matched in the c) The increased microbial activity uses up given table? [NEET – I, 2016] dissolved oxygen. d) The river water is still suitable for drinking as Microbe Product Application impurities are only about 0.1 per cent (a)Trichoderma Cyclosporin A Immunosuppressive 2. Select the correct statement from the following. polysporum drug [AIPMT PRE 2010] (b)Monascus Statins Lowering of blood a) Biogas is produced by the activity of aerobic purpureus cholesterol bacteria on animal waste. (c) Streptococcus Sterptockinase Removal of clot b) Methanobacterium is an aerobic bacterium found from blood vessel in rumen of cattle. (d)Clostridium Lipase Removal of oil c) Biogas, commonly called gober gas, is pure methane. butylicum stains d) Activated sludge-sediment in settlement tank 9. Match Column – I with Column – II and select the of sewage treatment plant is a right source of correct options using the codes given below: aerobic bacteria. [NEET – II, 2016] 3. Read the following four statements (A to D): Column I Column II [AIPMT MAINS 2012] A.Citric acid 1. Trichoderma a) Colostrums is recommended for the new born B.Cyclosporin A 2. Clostridium because it is rich in antigen. C.Statins 3. Aspergillus b) Chikungunya is caused by a gram negative D.Butyric acid 4. Monoscus bacterium. a) A:3, B:1, C:4, D:2 c) Tissue culture has proved useful in obtaining virus-free plants. b) A:1, B:4, C:2, D:3 d) Beer is manufactured by distillation of fermented c) A:3, B:4, C:1, D:2 grape juice d) A:3, B:1, C:2, D:4 How many of the above statements are wrong? a) Three b) Four c) One d) Two Chapter 10 - Biotechnology and Its Application 4. Which of the following are likely to be present in 1. Genetic engineering has been successfully used for deep sea water? [AIPMT 2013] producing [AIPMT RE 2010] a) Archaebacteria b) Eubacteria a) Transgenic mice for testing safety of polio c) Blue – green algae d) Saprophytic fungi vaccine before used in humans.

MCQs for Higher Studies 266

Competitive Questions for Higher studies NEW.indd 266 25-02-2019 18:55:28 b) Transgenic models for studying new treatments A) A bacterium B) Plasmid for certain cardiac diseases. C) Plasmodium D) Bacteriophage c) Transgenic cow Rosie which produces high fat a) (A), (B) and (D) only b) (A) only milk for making ghee. c) (A) and (C) only d) (B) and (D) only d) Animals like bulls for farm work as they have 8. Which one of the following palindromic base super power. sequences in DNA can be easily cut at about the 2. Some of the characteristics of Bt cotton are middle by some particular restriction enzyme? [AIPMT RE 2010] [AIPMT PRE 2010] a) Long fibre and resistance to aphids a) 5’ – CGTTCG – 3’ 3’ –ATGGTA -5’ b) Medium yield, long fibre and resistance to beetle pests. b) 5’-GATATG -3’ 3’ CTACTA -5’ c) High yields and production of toxic protein c) 5’ –GAATTC – 3’ 3’ – CTTAAG-5’ crystals which kill dipteran pests. d) 5’ –CACGTA -3’ 3’ –CTCAGT -5’ d) High yield and resistance to bollworms 9. Restriction endonucleases are enzymes which 3. Bacillus thuringiensis forms protein crystals which [AIPMT PRE 2010] contain insecticidal protein. This protein a) Make cuts at specific positions within the DNA [AIPMT MAINS 2010] molecule. a) Binds with epithelia cells of midgut of the insect b) Recognize a specific nucleotide sequence for pest ultimately killing it. binding of DNA ligase. b) Is coded by several genes including the gene cry. c) Restrict the action of the enzyme DNA polymerase. c) Is activated by acid pH of the foregut of the insect d) Remove nucleotides from the ends of the DNA pest. molecule. d) Does not kill the carrier bacterium which is itself 10. Stirred – tank bioreactors have been designed for resistant to this toxin. [AIPMT PRE 2010] 4. Read the following four statements (A to D) about a) Addition of preservatives of the product certain mistakes in two of them. [AIPMT MAINS 2011] b) Purification of the product a) The first transgenic buffalo, Rosie produced milk c) Ensuring anaerobic conditions in the culture vessel which was human alpha – lactalbumin enriched. d) Availability of oxygen throughout the process b) Restriction enzymes are used in isolation of DNA 11. There is a retriction endonuclease called EcoRI. What from other macromolecules. does ‘co’ part in it stand for? [AIPMT PRE 2011] c) Downstream processing is one of the steps of a) Coelom b) Coenzyme rDNA technology c) Coli d) Colon d) Disarmed pathogen vectors are also used in 12. Which one is true state regarding DNA polymerase transfer of rDNA into the host. used in PCR? [AIPMT PRE 2012] Which of the two statements have mistakes? a) It is used to ligate introduced DNA in recipient cells. a) B and C b) C and D b) It serves as selectable marker c) A and C d) A and B c) It is isolated from a virus. 5. The colonies of recombinant bacteria appear white d) It remains active at high temperature. in contrast to blue colonies of non-recombinant 13. For transformation, micro-particles coated with bacteria because of [AIPMT 2013] DNA to be bombarded with gene gun are made up of a) Non-recombinant bacteria containing β-galactosidase. [AIPMT PRE 2012] b) Insertional inactivation of α-galactosidase in non- a) Silver or Platinum b) Platinum or Zinc recombinant bacteria. c) Silicon or Platinum d) Gold or Tungsten c) Insertional inactivation of α-galactosidase in recombinant bacteria. Chapter 11 - Organisms and Population d) Inactivation of glycosidase enzyme in recombinant bacteria 1. Which one of the following is most appropriately 6. Which body of the Government of India regulates defined? [AIPMT MAINS 2010] GM research and safety of introducing GM organism a) Host is an organism which provides food to for public services? [AIPMT 2015] another organism. a) Bio-safety committee b) Amensalism is a relationship in which one species b) Indian council of agricultural research is benefited whereas the other is unaffected. c) Genetic engineering approval committee c) Predator is an organism that catches and kills d) Research committee on Genetic manipulation other organism for food. 7. In genetic engineering, a DNS segment (gene) of d) Parasite is an organism which always lives inside interest is transferred to the host cell through a the body of other organism and may kill it. vector. Consider the following four agents (A to D) 2. Study the four statements (1 to 4) given below and select in this regard and select correct option about which the two correct ones out of them. [AIPMT PRE 2010] one or more of these can be used as vector/vectors. a) A lion eating a deer and a sparrow feeding on grain [AIPMT MAIN 2010] are ecologically similar in being consumers.

267 MCQs for Higher Studies

Competitive Questions for Higher studies NEW.indd 267 25-02-2019 18:55:28 b) Predator star fish Pisaster helps in maintaining 9. When does the growth rate of a population following species diversity of some invertebrates. the logistic model equal zero? The logistic model is c) Predators ultimately lead to the extinction of prey given as dN/dt=rN(1-N/K): [NEET – I, 2016] species. a) When N/K is exactly one d) Production of chemicals such as nicotine, b) When N nears the carrying capacity of the habitat strychnine by the plants is metabolic disorders. c) When N/K equals zero The two correct statements are d) When dearth rate is greater than birth rate a) (B) and (C) b) (C) and (D) c) (A) and (D) d) (A) and (B) Chapter 12 - biodiversity and conservation 3. Which two of the following changes ( 1 to 4) usually 1. Select the correct statement about biodiversity tend to occur in the plain dwellers when they move to [AIPMT MAINS 2012] high altitudes(3500 m or more)? [AIPMT PRE 2010] a) Large scale planting of Bt cotton has no adverse A) Increase in red blood cell size effect on biodiversity. B) Increase in red blood cell production b) Western Ghats have a very high degree of species C) Increased breathing rate richness and endemism D) Increase in thrombocyte count c) Conservation of biodiversity is just a fad pursued a) (B) and (C) b) (C) and (D) by the developed countries. c) (A) and (D) d) (A) and (B) d) The desert areas of Rajasthan and Gujarat have a 4. Consider the following four conditions (A-D) and very high level of desert animal species as well as select the correct pair of them as adaptation to numerous rare animals. environment in desert lizards. [AIPMT PRE 2011] 2. Sacred groves are specially useful in[AIPMT MAINS 2012] The conditions: a) Preventing soil erosion A) Burrowing in soil to escape high temperature. b) Year-round flow of water in rivers B) Losing heat rapidly from the body during high c) Conserving rare and threatened species temperature d) Generating environmental awareness C) Bask in sun when temperature is low D) Insulating body due to thick fatty dermis. 3. The highest number of species in the world is a) (A) and (C) b) (B) and (D) represented by [AIPMT PRE 2012] c) (A) and (B) d) (C) and (D) a) Fungi b) Mosses c) Algae d) Lichens 5. People who have migrated from the planes to an area 4. Which of the following is not used for ex situ plant adjoining Rohtang Pass about six months back conservation? [AIPMT PRE 2012] [AIPMT PRE 2012] a) Field gene banks b) Seed banks a)Have more RBC’s and their haemoglobin has a c) Shifting cultivation d) Botanical gardens lower binding affinity to O2. 5. In which of the following both pairs have correct b) Are not physically fit to play games like football combination? [AIPMT 2015] c) Suffer from altitude sickness with symptoms like a) In situ conservation: National Park nausea, fatigue, etc. Ex situ conservation: Botanical Garden d) Have the usual RBC count but then haemoglobin b) In situ conservation: Cryopreservation has very high binding affinity to O2. Ex situ conservation: Wildlife Sanctuary 6. A biologist studies the population of eats in a barn. He found that the average natality was 250, average c) In situ conservation: Seed Bank mortality is 240, immigration is 20 and emigration to be Ex situ conservation: National park 30. The net increase in population is [AIPMT 2013] d) In situ conservation: Tissue culture a) 10 b) 15 c) 05 d) Zero Ex situ conservation: Sacred groves 7. An association of individuals of different species 6. Cryopreservation of gametes of threatened species living in the same habitat and having functional in viable and fertile condition can be referred to interaction is: [RE-AIMPT 2015] as [AIPMT 2015] a) Biotic community b) Ecosystem a) In situ conservation of biodiversity c) Population d) Ecological niche b) Advanced ex situ conservation of biodiversity 8. Gause’s principle of competitive exclusion states c) In situ conservation by sacred groves that: [NEET – I, 2016] d) In situ cryo-conservation of biodiversity a) More abundant species will exclude the less abundant species through competition 7. The species confined to a particular region and not b) Competition for the same resources excludes found elsewhere is termed as [RE-AIPMT 2015] species having different food preferences a) Alien b) Endemic c) Rare d) Keystone c) No two species can occupy the same niche 8. Which of the following National Parks is home to indefinitely for the same limiting resources the famous musk deer or hangal? [NEET-II, 2016] d) Larger organisms exclude smaller ones through a) Bandhavgarh National Park, Madhya Pradesh competition b) Eaglenest Wildlife Sanctuary, Arunachal Pradesh

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Competitive Questions for Higher studies NEW.indd 268 25-02-2019 18:55:28 c) Dachigam National Park, Jammu & Kashmir 7. A scrubber in the exhaust of a chemical industrial d) Keibul Lamjao National Park, Manipur plant removes a) Gases like sulphur dioxide. Chapter 13 - Environmental Issues b) Particulate matter of the size 5 micrometer or 1. DB is a standard abbreviation used for the above. quantitative expression of [AIPMT PRE -2010] c) Gases like ozone and methane a)The density of bacteria in a medium d) Particulate matter of the size 2.5 micrometer or less b) A particular pollutant 8. Rachel Carson’s famous book ‘Silent Spring’ is related c) The dominant bacillus in a culture to [AIPMT-2015] d) A certain pesticide a) Pesticide pollution b) Noise Pollution 2. Which one of the following expanded forms of the c) Population explosion following acronyms is correct? [AIPMT PRE-2011] d) Ecosystem management a)UNEP United Nations Environmental Policy 9. Which of the following is not one of the primary health b)EPA Environmental Pollution Agency risks associated with greater UV radiation through c)IUCN International Union for Conservation the atmosphere due to depletion of stratospheric of Nature and Natural Resources ozone? [AIPMT-2015] a) Increased skin cancer d)IPCC International Penal for climate Change b) Reduced immune system 3. In an area where DDT had been used extensively c) Damage to eyes the population of birds declined significantly d) Increased liver cancer because 10. Increase in the concentration of the toxicant at [AIPMT PRE-2012] successive trophic levels is known as [RE AIPMT-2015] a) Birds stopped laying eggs a) Biodeterioration b) Earthworms in the area got eradicated. b) Biotransformation c) Cobras were feeding exclusively on birds. c) Biogeochemical cycling d) Many of the birds eggs, laid, did not hatch. d) Biomagnifications 4. Which one of the following is a wrong statement? 11. A river with an inflow of domestic sewage rich in AIPMT PRE-2012] organic waste may result in: [NEET-I, 2016] a) Most of the forests have been lost in tropical areas. a) Drying of the river very soon due to algal bloom b) Ozone in upper part of atmosphere is harmful b) Increased population of aquatic food web organisms to animals. c) An increased production of fish due to c) Greenhouse effect is natural phenomenon biodegradable nutrients d) Eutrophication is a natural phenomenon in d) Death of fish due to lack of oxygen freshwater bodies. 12. A lake which is rich in organic waste may result in 5. Measuring Biochemical Oxygen Demand (BOD) is a [NEET-II, 2016] method used for [AIPMT PRE-2012] a) Drying of the lake due to algal bloom a) Estimating the amount of organic matter in b) Increased population of fish due to lots of nutrients sewage water. c) Mortality of fish due to lack of oxygen b) Working out the efficiency of oil driven automobile d) Increases population of aquatic organisms due to engines. minerals c) Measuring the activity of saccharomyces cerevisiae 13. The highest DDT concentration in aquatic food in producing curd on a commercial scales chain shall occur in [NEET-II, 2016] d) Working out the efficiency of RBCs about their a) Seagull b) Crab capacity to carry oxygen c) Cell d) Phytoplankton 6. Kyoto Protocol was endorsed at [AIPMT -2013] a) CoP-3 b) CoP-5 c) CoP-6 d) CoP-4

269 MCQs for Higher Studies

Competitive Questions for Higher studies NEW.indd 269 25-02-2019 18:55:28 Zoology – Class XII List of Authors and Reviewers Advisory Committee Members Subject Expert and Coordinator Domain Experts and Chair person Dr. S. Shameem Dr. P. Sarala Deputy Director Associate Professor, Department of Zoology, Dr. Sultan Ahmed Ismail State Council of Educational Research and Training, Quaid-e-Millath College for Women, Chennai. Scientist Chennai. Ecoscience Research Foundation, Chennai. Dr. Sumit Rose Coordinators Associate Professor, Department of Zoology, Dr. P.K. Kaleena Presidency College, Chennai. Associate Professor, Dr. V.T. Shanthi Department of Zoology, Senior Lecturer, Dr. B. Meena Associate Professor, Department of Zoology, District Institute of Education and Tranning, Tirur. Presidency College, Chennai. Presidency College, Chennai. Mrs. B. Selvi Assistant Professor, Dr. E. Malathi Associate Professor, Department of Zoology, Content Writers SCERT, Chennai. Mr. M. Mayilsamy Queen Mary’s College, Chennai. Senior Lecturer, Prospects of Zoology Reviewers District Institute of Education and Tranning, Krishnagiri. Dr. T. Sankara Saravanan Dr. Dinesh Kumar Deputy Director Reader, NCERT, New Delhi. Dr. P. Sekar Tamil Nadu Textbook and Educational Assistant Professor Services Corporation, Chennai. Dr.Vareishang Tangu Govt. Institute of Advanced Assistant Professor in Zoology Study in Education (Autonomous), Translators RIE NCERT, Mysore. Saidapet, Chennai. Dr. S. Muthazhagu Dr. Chitralekha Ramachandran Dr. S. Ganesapandian Associate Professor (Rtd.) Professor (Rtd.), Head Master A.A Govt. Arts College, Cheyyar. Stella Mary's College, Chennai. Government Higher Secondary School, Kadukkai Valasai, Ramanathapuram Dist. Mr. M. Sivaguru Ms. Hemamalini Akundy Head Master Assistant HOD., Salwan Public School, Dr. J. Savarimuthu Michael Sri Ramakrishna Vidyasala Higher Secondary School, Gurgaon. P.G. Assistant in Zoology Chidambaram, Cuddalore. Carmel Higher Secondary School, Content Readers Nagercoil, Kanyakumari Dist. Mr. S. Maheswaran Head Master Dr. Mazher Sulthana Mr. Alen Godfrey R. Jose Govt. Boys Higher Secondary School, Associate Professor in Zoology (Rtd.), P.G. Assistant in Zoology Presidency College, Chennai. Sayal Gudi, Ramanathapuram Dist. M.C.C Mat.Higher Secondary School, Chetpet, Chennai. Dr. R. Saravanan Mr. V. Rajendran Assistant Professor in Zoology Mr. L. Sivan pillai P.G. Assistant in Zoology Dr. Ambedkar Govt. Arts College, Government Higher Secondary School, Vyasarpadi, Chennai. P.G. Assistant in Zoology Aragalur, Salem Dist. Bharath Senior Secondary School, Dr. N. Sarojini Adyar, Chennai. Mr. S. Natarajan Assistant Professor in Zoology P.G. Assistant in Zoology, Bharathi Women’s College, Chennai. Mrs. P. Sophia Selvakumari Model School, Kolli Hills, Namakkal Dist. P.G. Assistant in Zoology Mr. K. Senthil Vel Mr. S. Munusamy Bentinck Higher Secondary School for Girls, P.G.Assistant in Zoology Head Master. (Rtd.), Vepery, Chennai. A.S. Govt. Higher Secondary School, GHSS., Velachery, Chennai. Mr. K.P. Muthuswamy Sholavandan, Madurai Dist. P.G. Assistant in Zoology Mr. S.P. Sabarinathan Art and Design Team C.S.M.A. Higher Secondary School, P.G.Assistant in Zoology M.M. Kovilur, Dindigul Dist. Govt. Higher Secondary School, Illustrators Mr. V. Elangovan Sengurichi, Dindugul Dist. Gopu Rasuvel P.G. Assistant in Zoology Mr. G. Kirubananthan N. Prabhakar Sir M. Ct. M. Higher Secondary School, P.G. Assistant in Zoology Murugesan Veeraiyan Pursawalkam, Chennai. Govt. Higher Secondary School, Santhanakrishnan Anakaputhur, Kanchipuram District. Mr. M. William Vijayraj Vimal Shanmugam P.G. Assistant in Zoology Dr. P. S. S. Mpl. Higher Secondary School, ICT Coordinators Layout In-House Kanchipuram. Rajesh Thangappan R.Kamesh Mr. N. Senthil Kumar SGT., Govt. Primary School, C. Prasanth PG Assistant in Zoology Pinjanur, Cuddalore Dist. Govt Boys Higher Secondary School, Petchimuthu Thalaivasal, Salem District. Santhiyagu Stephen Mrs. Reena Alfred QR Management Team P. Prasanth Principal R. Mathan Raj Alpha Higher Secondary School, J.F. Paul Edwin Roy, B.T, PUMS -Rakkipatty, Salem. Pakkirisamy Annadurai CIT, Saidapet, Chennai. M. Murugesan, B.T, Wrapper Design Mr. R. Perumal Pums. Pethavelankottagam, Kathir Arumugam Principal Muttupettai, Thiruvarur. Velammal Vidhyashram, In-House QC Surapet, Chennai. V. Padmavathi, B.T, GHS, Vetriyur, Manohar Radhakrishnan Ariyalur. Arun Kamaraj P. Co-ordination Ramesh Munisamy This book has been printed on 80 G.S.M. Elegant Maplitho paper. Printed by offset at:

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