Test: Environmental Issues - 1 (Old NCERT) - NEET MCQ

Air pollution is the fifth leading cause of death in India, with 620,000 premature deaths in 2010. It comes after indoor air pollution, tobacco smoking, high blood pressure, childhood underweight, low nutritional status, and alcohol use. World Health Organisation, says air pollution has become one of the top 10 killers in the world. GBD tracks deaths and illnesses from all causes across the world.

The expanded form of DDT is dichloro diphenyl trichloroethane. This is the first modern insecticide in the year 1940's.

In normal adults, the enzyme which catalyses conversion of MHb into Hb is MHb reductase enzyme. MHb is inactive forms that is converted into Hb that carries oxygen in blood.

Noise pollution is a kind of air pollution that may cause permanent impairment of hearing ability of human beings if its loudness is equal to or more than 150 dB.

As per supreme court guidelines 2005, a loud speaker or a public address system are not permitted at night between 10:00 pm to 6:00 am except in closed premises for communication within, like auditorium, conference room, community halls and banquet halls. Under the Environment (Protection) Act, 1986, rules for noise pollution level are framed for ambient air quality standards of noise for different areas/ zones.

Nitrogen oxides is released by lightening, fluorides from coal burning, PCBs from burning plastics and chlorofluorocarbons from jet aeroplanes emissions.

Methyl mercury is the neurotoxic form of Mercury, which can be directly absorbed by fishes. From fishes they enter to food chain and to human body causing bio-magnification.

Oil splits over the water bodies prevents the oxygenation of water. The dissolved oxygen in water is used by aquatic organisms for respiration. It is physical pollutant.

A number of organisms grow in polluted water. The species whose concentration is highest in polluted water is called as index species as this species indicate the presence of particular kinds of pollutant in water.

Dystrophic lake have too low accumulation of dissolved nutrients to support abundant plant life so, they have very low productivity.

On the basis of emission of pollutants in water bodies, there are point and diffusion sources of water pollution. Fertilizers are example of diffusion sources of water and industrial discharge pipes are example of point source of water pollution. So, statement i is correct only.

Low biological oxygen demand (BOD) will be characteristic feature of an oligotrophic lake. In oligotrophic lake concentration of nutrients are very low so a few organisms only survive and BOD is comparatively low.

Ozone is of two type one is found is stratosphere(upper part of atmosphere) and called as stratospheric ozone (good ozone) it prevents harmful UV rays to reach us. Another is found in troposphere(lower part of atmosphere) and called as tropospheric ozone (bad ozone) its is formed by human activities and harmful for living organisms.

Biopetrol is fuel having characteristic similar to petrol but is produced from palmitic acid.So, it is not a biofuel. Biodiesel, marsh gas and ethanol are biofuels produced by action of microbes.

Mass destruction of aquatic life will be caused by broad spectrum pesticides. Broad spectrum pesticides are effective against large number of pests whether useful or harmful. These pesticides reaches to water bodies along with rain water.

Particulate air pollutant like soot, fly ash, dust of various types, pollens, spores, fur, hair can be differentiated as settable and suspended particulate matter pollutant. Their effect on the environment depends upon the size of the particles. According to CPCB, particulate matter of 2.5 micrometres or less in diameter are responsible for causing great harm to human health. They are inhaled deep into the respiratory tract upto lungs and causes respiratory problems and may even lead to death

The biological amplification of DDT in the various trophic levels is known as biomagnifications. The harmful non-biodegradable chemicals accumulate at each trophic level of a food chain.

Spraying of DDT produces pollution of air, water and soil. DDT is used as pesticides in agricultural field. It is non-biodegradable and reach to water bodies to pollute it. Some DDT also remains present in air as mist.

Anaerobic decomposition of plants in water produces methane gas in paddy field. This gas is involved in global warming as methane is a green house gas beside carbon dioxide.

Out of the given gases carbon monoxide is the most toxic gas as it combine with hemoglobin present in blood and reduce the oxygen carrying capacity of blood.

DDT is a non-biodegradable pollutant used as pesticides in agricultural field. It pollutes the air, water and soil if used in form of spray.

According to U.S. greenhouse gas emissions report methane (CH₄) accounted of the second largest percentage of greenhouse gases after Chlorofluorocarbon (CFCs).

Greenhouse effect causes increase in temperature of earth. Homeotherms can tolerate high temperature. So, homeotherms will be able to cope with the effect of green house effect.

Earth is protected from ultra-violet radiations by means of ozone layer. Ozone layers are present in stratosphere of atmosphere that absorbs the UV radiations and protect us from its harmful effects.

Ozone depletion shall cause higher incidence of skin cancer, cataract and decreased immunity.