Tuesday, April 10, 2018

AHSEC Class 11: Environmental Education Solved Question Paper' 2015

Full Marks: 30
Time: 1 hour.
The figures in the margin indicate full marks for the questions.

1. Fill in the blanks:        1x5=5
(a) The components of biotic environment are Producers, Consumers and Decomposer.
(b) Population is a group of individuals of the same species occupying a given area at a given time.
(c) The Wildlife Protection Act was enacted in the year 1972 in India.
(d) Groundwater is a non-renewable kind of natural resource.
(e) The causal organism of cholera is Vibrio cholerae.
2. Write very short answers of the following:    1x5=5
(a) What is the role of ozone present in the stratosphere?
Ans. Ozone is a pale blue gas, mostly present in the stratosphere which is extended upto 50 km above the surface of the earth. Ozone strongly absorbs a large portion of sun’s ultraviolet radiation and thus protects the living organisms on earth from the harmful effects of UV radiations of the sun.
(b) What is trophic level?
Ans: Every organism in an ecosystem can be assigned a feeding level, referred to as the trophic level.

(c) Mention two conservative measures for land resources.
Ans. Land resources can conserve the following points:
a)      Soil erosion can be minimized by Afforestation in the hilly slopes.
b)      Use of pesticides and fertilizers should be banned and organic fertilizers should be encouraged.
(d) Name any two principal pollutants emitted by vehicles.
Ans: Hydrocarbons (HC), Nitrogen oxides (NOx), Carbon monoxide (CO), Sulfur dioxide (SO2), Hazardous air pollutants (toxics), Greenhouse gases.
(e) Write the full form of WCED.
Ans: World Commission On Environment And Development
3. Answer any five questions from the following:                            2x5=10
(a) Write the objectives and the guiding principles for environmental education.
Ans: The objectives and the guiding principles for environmental education are:
a)      Awareness and sensitivity to the environmental and environmental challenges.
b)      Knowledge and understanding of the environment and environmental challenges.
c)       Attitude of concern for the environment and motivation to improve or maintain environmental quality.
(b) What is meant by ecosystem?
Ans: An ecosystem is a community of organisms involved in a dynamic network of biological, chemical and physical interactions between themselves and with the non-living components.
(c) What is genetic biodiversity?
Ans: This is the diversity of genes within a species, which are passed down the generations. It is this type of diversity that gives rise to the varieties of species.
(d) Write brief note on mineral resources of North-East India.
Ans: Most of the accounted mining industries in the northeastern region are located in the states of Assam and Meghalaya. Assam is known for its petroleum and natural gas reserves, coal, limestone and minor minerals; Meghalaya has established coal and limestone mining industries.
(e) Explain the effects of deforestation on environment.
Ans: Deforestation can have a negative impact on the environment. The most dramatic impact is a loss of habitat for millions of species. Eighty percent of Earth's land animals and plants live in forests, and many cannot survive the deforestation that destroys their homes. Deforestation also drives climate change.
(f) What do you mean by global warming?
Ans: Due to different natural as well as anthropogenic activities the concentration of the greenhouse gases in the atmosphere has increased during the past several decades. Scientists estimate that the earth’s average temperature has increases by 0.3 – 0.60CC since the beginning of the last century. The rise in temperature due to the blanketing effect of increased level of greenhouse gases is termed as global warming.
(g) What are natural and artificial disasters?
Ans: Natural Disasters: Natural disasters are earthquakes, floods, cyclones, volcanic eruptions, drought, heavy rains, hailstorms, forest fire, heavy snowfalls, Tsunamis, etc.
Artificial or Man-made Disasters: Industrial accidents, air crashes, train accidents, attack by terrorists, ethnic clashes, epidemics and fire related accidents are some of the man-made disasters.
(h) Write any two national conservation strategies for biodiversity.
Ans. Indian has several Acts in force which have a bearing on the conservation of biodiversity. Some of these Acts are:
a)      Environment Protection Act, 1986: This act relates to general measures to protection the environment, such as restriction on industrial and other processes or activities in specified areas.
b)      Forest (Conservation) Act, 1980: This act primarily focuses on prohibiting or regulating non forest use of forest lands.
4. Answer any two from the following:                                 5x2=10
(a) How does environmental awareness help to protect our environment?
Ans: The world today is confronted with the great problem of environmental degradation and pollution. Different types of pollution, fast depleting forest resources, rapid population explosion, expanding industrialization, unplanned urbanization, mining, soil erosion etc have created ecological imbalances in recent years. Man’s quest for economic development has been mainly responsible for the ruthless exploitation of natural resources. Moreover highly materialistic, greedy and luxurious life style attitude of human race indiscriminately exploited or imprudently destroyed the natural resources. All these activities have become a threat to the very existence of a number of living organisms. So creation of public awareness is must to protect the environment from further deterioration.
(b) Write an account on structure and functions of an ecosystem.
Ans: An ecosystem is a community of organisms involved in a dynamic network of biological, chemical and physical interactions between themselves and with the non-living components.
Each ecosystem has two main components (Structure):
(1) Abiotic Components: Ans. The physical and chemical components of an ecosystem constitute the abiotic structure. Under chemical components, major nutrients like carbon, nitrogen, phosphorous, oxygen, potassium etc.
(2) Biotic Components: The plants, animals and the micro-organisms present in an ecosystem form the biotic component. Biotic components may be divided into Autotrophs and Heterotrophs.

Function of Ecosystem: An ecosystem is a discrete structural, functional and life sustaining environmental system. The environmental system consists of biotic and abiotic components in a habitat. Biotic component of the ecosystem includes the living organisms; plants, animals and microbes whereas the abiotic component includes inorganic matter and energy.
Abiotic components provide the matrix for the synthesis and perpetuation of organic components (protoplasm). The synthesis and perpetuation processes involve energy exchange and this energy comes from the sun in the form of light or solar energy.
(c) What is water pollution? Identify the sources of water pollution. Mention few effects of water pollution on human health.
Ans: Meaning: Water pollution is the pollution of bodies of water, such as lakes, rivers, seas, the oceans, as well as groundwater. It occurs when pollutants reach these bodies of water, without treatment. Waste from homes, factories and other buildings get into the water bodies.
Sources of Water Pollution:  
a)      Domestic wastes.
b)      Industrial effluents.
c)       Agricultural wastes.
d)      Run off from urban areas.
e)      Soluble effluents.
f)       Oil spills.
Effects of Water Pollution
Domestic and hospital sewage contain many undesirable pathogenic microorganisms, and its disposal into a water without proper treatment may cause outbreak of serious diseases, such as, amoebiasis dysentery, typhoid, jaundice, cholera, etc. Metals like lead, zinc, arsenic, copper, mercury and cadmium in industrial waste waters adversely affect humans and other animals.
(d) Describe the different steps involved in rainwater harvesting.
Rainwater harvesting in urban areas can have manifold reasons. To provide supplemental water for the city's requirement, to increase soil moisture levels for urban greenery, to increase the ground water table through artificial recharge, to mitigate urban flooding and to improve the quality of groundwater are some of the reasons why rainwater harvesting can be adopted in cities. In urban areas of the developed world, at a household level, harvested rainwater can be used for flushing toilets and washing laundry. Indeed in hard water areas it is superior to mains water for this. It can also be used for showering or bathing. It may require treatment prior to use for drinking. 
The first step is collecting the rain water, like on a roof top. Then transporting the water, like with a gutter and downspout. The next step is storage of the water and there are several options here. You can collect in in a tank for your use, usually it is passed through a sand and gravel filter before storage. It can be collected on an open pond or into pits or trenches to restore ground water, or into an existing well.