Carbon monoxide has more affinity for haemoglobin than oxygen. This result in formation in carboxyhemoglobin at any or all of the oxygen-binding sites of hemoglobin, reducing the ability of the hemoglobin molecule to release oxygen bound to other oxygen-binding sites. This is known as carbon monoxide poisoning. Answer : (c)

Pollution indicators plants like are very sensitive to pollutant. They do not grow in areas where there is high level of pollution. Answer : (c)

Exposure to high levels of lead may cause anemia, weakness, and kidney and brain damage. Exposure to cobalt may cause weight loss, dermatitis, and respiratory hypersensitivity. Inhaled insoluble uranium compounds can damage the respiratory tract. Answer : (d)

Larval stoneflies are sensitive to changes in water quality. In particular, stoneflies are sensitive to changes in dissolved oxygen and water temperature. Stoneflies need a high amount of dissolved oxygen (DO) to live comfortably. When the D.O. falls or the temperatures rise, stoneflies disappear. Polluted water have less amount of dissolved oxygen and so stonefly larvae cannot be found in it. Answer : (a)

CO2 accounts for about 76 percent of total greenhouse gas emissions. Methane contributes 16 percent of greenhouse gas emissions and nitrous oxide contributes 6 percent to global emissions. Answer : (d)

Biochemical oxygen demand (BOD) is the amount of dissolved oxygen needed (i.e. demanded) by aerobic biological organisms to break down organic material present in a given water sample at certain temperature over a specific time period. Answer : (c)

Blackfoot disease is a characteristic vascular disease associated with long-term exposure to inorganic arsenic Secondary wastewater treatment processes use microorganisms to biologically remove contaminants from wastewater. Secondary biological processes can be aerobic or anaerobic, each process utilizing a different type of bacterial community. pyrolysis represents a process of thermal degradation of the waste in the total absence of air that produces recyclable products, including char, oil/wax and combustible gases. Tubifex tubifex and Limnodrilus hoffmeisteri are the pollution-indicator oligochaete species identified in the fresh water ponds, which reveals that the studied ponds are subjected to pollution. Biomagnification process occurs when certain toxic chemicals and pollutants such as heavy metals, pesticides or polychlorinated biphenyls (PCBs) compounds, usually non-biodegradable pollutants go up the food chain by working their way through the environment and into the soil or the water systems. Answer : (d)

We measure sound intensity (also referred to as sound power or sound pressure) in units called decibels. The hertz (symbol: Hz) is the derived unit of frequency in the International System of Units (SI) A fathom is a unit of length in the imperial and the U.S. customary systems equal to 6 feet, used especially for measuring the depth of water. A nanometer is one millionth of a milimeter. Answer : (d)

Eutrophication, distrophication or hypertrophication, is when a body of water becomes overly enriched with minerals and nutrients which induce excessive growth of algae. This process may result in oxygen depletion of the water body. Answer : (a)

Biomagnification, also known as bioamplification or biological magnification, is any concentration of a toxin, such as pesticides, in the tissues of tolerant organisms at successively higher levels in a food chain. In the above options, birds come at successively higher level in food chain Answer : (c)

Photochemical oxidants are the secondary pollutants that are formed when the primary pollutants like hydrocarbons, oxides of sulphur, oxides of nitrogen react with sunlight. The major products of this reaction include tropospheric ozone, peroxyacetyl nitrate and aldehydes. They also contribute to the formation of the photochemical smog. Answer : (c)

Basel Convention, is an international treaty that was designed to reduce the movements of hazardous waste between nations not for biodiversity conservation The Kyoto Protocol is an international treaty which extends the 1992 United Nations Framework Convention on Climate Change (UNFCCC) that commits state parties to reduce greenhouse gas emissions The Montreal Protocol, finalized in 1987, is a global agreement to protect the stratospheric ozone layer by phasing out the production and consumption of ozone-depleting substances (ODS) The Ramsar Convention on Wetlands of International Importance especially as Waterfowl Habitat is an international treaty for the conservation and sustainable use of wetlands. Answer : (b)

Acid rain is caused by emissions of sulfur dioxide and nitrogen oxide, which react with the water molecules in the atmosphere to produce acids. Acid rain corrodes the marble (calcium carbonate) of Taj Mahal. It causes damage to this wonderful structure, causing yellowing of marble. Answer : (a)

Strontium-90 readily enters into the food chain from the soil when absorbed by the plants. Its persistent nature results in the biomagnification. Answer : (d)

When trees are cut down and burned or allowed to rot, their stored carbon is released into the air as carbon dioxide. And this is how deforestation and forest degradation contribute to global warming. Thus the assertion is correct. The primary greenhouse gases in Earth's atmosphere are water vapor carbon dioxide, methane, nitrous oxide, ozone, CFCs. Thus reason is correct but it is not correct explanation for assertion as both statement are not inter-related. Answer : (b)

The vast majority of greenhouse gas emissions come from combustion of fossil fuels, principally coal, oil, and natural gas, with additional contributions coming from deforestation, traditional rice cultivation, increased use of refrigerators and air conditioners, use of autombiles and industries. Answer : (d)

Aquatic oligochaetes are known for their use as water quality indicators, especially in areas with urban and sewage effluent. In particular, the oligochaete species Tubifex tubifex is used as a water quality indicator because of its ability to tolerate low oxygen conditions, the presence of heavy metals, and other environmental conditions. Answer : (a)

oxides of sulphur, oxides of nitrogen and oxides of carbon react with water and precipiate in the form of nitric acid and sulphuric acid called acid rains. Acid rains have resulted in the corrosion of the marble, making it to appear yellow. Mathura refinery releases oxides of nitrogen, sulphur. Answer : (c)

Answer : (c)

Lichens are well known as sensitive indicators of air pollution, particularly for sulfur dioxide. Answer : (b)

A greenhouse gas is a gas that absorbs and emits radiant energy within the thermal infrared range. The primary greenhouse gases in Earth's atmosphere are water vapor, carbon dioxide, methane, nitrous oxide, and ozone Answer : (c)

Novel organic substances are not easily degraded because organisms lack previous exposure and have thus not evolved specific detoxification and excretion mechanisms, as there has been no selection pressure from them. These substances are consequently known as "persistent organic pollutants" or POPs. These are the substances that biomagnify. Examples of persistant organic pollutants (POPs) are DDT (dichlorodiphenyltrichloroethane) Hexachlorobenzene (HCB) PCBs (polychlorinated biphenyls). All these POPs are organochlorine insecticides. Answer : (a)

A new WWF study reveals the likely impacts of global climate change on snow leopard habitat in the Himalayas. The WWF study indicates that if greenhouse gas emissions continue to increase steadily, 30 percent of snow leopard habitat in the Himalayas may be lost to shifts in its treeline habitat. Answer : (d)

Domestic sewage contains large amounts of organic matter. When domestic sewage mixes with river water, this will lead to increase in BOD or Biochemical Oxygen Demand. BOD is the amount of oxygen required by bacteria to decompose organic matter in one litre of polluted water. If the water is more polluted, more will be the BOD because more will be the organic matter present in it and hence, more oxygen will be required to decompose it. Hence, the dissolved oxygen will be used up by the bacteria to decompose the organic matter. Answer : (c)

Answer : (a)

Lead can be released directly into the air, as suspended particles. Historic major sources of lead air emissions were motor vehicles and industrial sources. Lead is a major air pollutant. Answer : (c)

High concentrations of DDT disturb calcium metabolism in birds, which causes thinning of eggshell and their premature breaking, eventually causing decline in bird populations Answer : (d)

'silent zone' includes areas that lie within 100 meters of the premises of schools, colleges, hospitals and courts. The permissible noise limit in this zone is 50 dB during the day and 40 dB during the night. Answer : (c)

DDT is non-biodegradable pollutant and biomagnify. It pollutes air, water and soil. Answer : (d)

Pyrethrum is the crude extract obtained from the flowers of Chrysanthemum plant. Dichlorodiphenyltrichloroethane or DDT is a crystalline, colourless and odourless compound which is used as an insecticide. DDT is considered a possible human carcinogen. Rotenone is a colourless and odourless crystalline compound used as a broad spectrum pesticide and insecticide. Humulin is the genetically engineered insulin hormones of humans. Hence, DDT is more hazardous to human health. Answer : (b)