1.Carbon monoxide poisoning is the most common type of fatal air poisoning in many parts of the world. What makes it such a fatal gas?
[A] CO dissolves in cytoplasm and functions as an inhibitor of the crucial enzymes for metabolism
[B] CO competes with Haemoglobin for Oxygen intake
[C] CO dissolves in blood Plasma and spreads toxicity
[D] CO converts into Carbon Dioxide in presence of water in Blood
SHOW ANSWER
Explanation: Carbon monoxide is colourless, odourless, and tasteless, but highly toxic because it combines with haemoglobin to produce carboxyhemoglobin, which usurps the space in haemoglobin that normally carries oxygen, but is ineffective for delivering oxygen to bodily tissues. Concentrations as low as 667 ppm may cause up to 50% of the body’s hemoglobin to convert to carboxyhemoglobin. The impact is irreversible and that is why that even after available of oxygen, the carboxyhemoglobin does not allow the Oxygen to be taken up. ©navclasses
2.In the context of environment, consider the following statements about CITES (Convention on International Trade in Endangered Species):
1.CITES is an intergovernmental organisation, restricting international trade of endangered fauna and flora.
2.CITES was drafted of a resolution adopted at general conference of UNESCO.
3.CITES is legally binding on the states ratifying the agreement.
Which of the above statements is/are correct?
[A] 1 Only
[B] 2 and 3 Only
[C] 1 and 3 Only
[D] 1, 2 and 3
SHOW ANSWER
Explanation: Second statement is incorrect because CITES was drafted under UNEP. CITES (the Convention on International Trade in Endangered Species of Wild Fauna and Flora) is an international agreement between governments. Its aim is to ensure that international trade in specimens of wild animals and plants does not threaten their survival. As a result of convention, all import and export; re-export of plant and animal species covered by the Convention has to be authorized through a licensing system. ©navclasses
3.With reference to ecological succession, which among the following community is also known as a ‘pioneer community’ due to its ability to colonize bare rock?
[A] Fungi
[B] Blue Green algae
[C] Lichens
[D] Mosses & Liverworts
SHOW ANSWER
Explanation: A pioneer community is a collection of organisms able to colonize bare rock. Lichens help break down rock and accumulate debris, helping to form a thin soil layer. The soil layer begins to support small forms of life. ©navclasses
4.The highest Biological Oxygen Demand (BOD) can be expected in __?
[A] A running river
[B] A running polluted river
[C] Treated Municipal waste water
[D] Untreated Municipal waste water
SHOW ANSWER
Explanation: BOD is amount of dissolved oxygen needed by aerobic biological organisms in a body of water to break down organic material present in a given water sample at certain temperature over a specific time period, for running rivers, it would be minimum and for Untreated Municipal waste water it would be maximum. ©navclasses
5.Common but Differentiated Responsibilities and Respective Capabilities (CBDR–RC):
1. is a principle within the framework of United Nation Environment Programme
2. has been adopted as a part of Rio Declaration on Environment and Development
Which of the above statements is/are correct?
[A] 1 Only
[B] 2 Only
[C] Both 1 & 2
[D] Neither 1 nor 2
SHOW ANSWER
Explanation: First statement is incorrect because Common but Differentiated Responsibilities and Respective Capabilities (CBDR–RC) is a principle within the United Nations Framework Convention on Climate Change (UNFCCC). Second statement is correct. ©navclasses
6.Which of the following is / are consequences of deforestation?
1. Reduction in atmospheric moisture
2. Increase in emission of carbon dioxide
3. Increase in thickness of ice sheets on earth
4. Slope stabilization
Select the correct option from the codes give below:
[A] 1 Only
[B] 1 & 2 Only
[C] 1, 2 & 4 Only
[D] 1, 2, 3 & 4
SHOW ANSWER
Explanation: Deforestation leads to increase in green house gases on earth and thus increase in temperature of earth surface. This in turn leads to melting of ice and reduction in size of ice-sheets on earth. Slope stabilization reduces due to increase in erosion activities by wind, water etc. after deforestation. ©navclasses
7.Consider the following pollutants:
1. Ground level ozone
2. Sulphur oxides
3. Volatile organic compounds
Which of the above is/are primary pollutant(s)?
[A] 1 Only
[B] 2 & 3 Only
[C] 1 & 2 Only
[D] 2 Only
SHOW ANSWER
Explanation: Ground level ozone is a secondary pollutant ©navclasses
8.Which of the following pollutants is the major reason behind adverse affect on the white marbles of Taj Mahal?
[A] Black carbon
[B] Nitrogen oxides
[C] Brown carbon
[D] Sulphur dioxide
SHOW ANSWER
Explanation: Correct answer is Brown Carbon, which contributes 30 % in damage to Taj Mahal. As per recent analysis of Centre for Science and Environment (CSE), Sulphur dioxide is not the major contributor to damage now, as it was during 1990s. Vehicle emissions are the biggest contributors for brown and black carbon. ©navclasses
9.What is / are the difference(s) between an Ecosystem and a Biome?
1. An ecosystem comprises biotic as well as abiotic components , while a biome has only biotic components
2. An ecosystem is generally larger part of Biosphere, while a Biome is a smaller part.
Which among the above statements is/ are correct?
[A] Only 1
[B] Only 2
[C] Both 1 & 2
[D] Neither 1 nor 2
SHOW ANSWER
Explanation: Ecosystem versus Biome Biomes are groups of ecosystems that share similar conditions in an environment. The first thing we have to note that a Biome is a larger part that may comprise many ecosystems. Technically, Biomes are groups of ecosystems that share similar conditions in an environment. A biome is a large area with similar flora, fauna, and microorganisms. Most of us are familiar with the tropical rainforests, tundra in the arctic regions, and the evergreen trees in the coniferous forests. Each of these large communities contains species that are adapted to its varying conditions of water, temperature, and soil. For instance, polar bears thrive in the arctic while cactus plants have a thick skin to help preserve water in the hot desert. So, the typical characteristics of the Biomes are that they have:
Similar climatic conditions
Same kind of abiotic and biotic factors spread over a large area creating a typical ecosystem over that area.
However, please note that a Biome as well as an ecosystem may have many species. In fact, the biomes are divided on the basis of factors such as plant structures (such as trees, shrubs, and grasses), leaf types (such as broadleaf and needle leaf), plant spacing (forest, woodland, savanna), and climate. ©navclasses
10.Consider the following statements:
1. Wadden Sea Agreement has been concluded for the protection of Seals
2. Basel Convention in context with environment is related to Hazardous wastes
Which among the above statements is / are correct?
[A] Only 1
[B] Only 2
[C] Both 1 & 2
[D] Neither 1 nor 2
SHOW ANSWER
Explanation: Agreement on the Conservation of Seals in the Wadden Sea is an agreement between Wadden Sea countries, aimed at protection of seals and concluded in the aegis of Convention on Migratory Species (CMS) in 1990. The Basel Convention on the Control of Transboundary Movements of Hazardous Wastes and Their Disposal, usually known simply as the Basel Convention, is an international treaty that was designed to reduce the movements of hazardous waste between nations, and specifically to prevent transfer of hazardous waste from developed to less developed countries (LDCs). It does not, however, address the movement of radioactive waste. The Convention is also intended to minimize the amount and toxicity of wastes generated, to ensure their environmentally sound management as closely as possible to the source of generation, and to assist LDCs in environmentally sound management of the hazardous and other wastes they generate. The Convention was opened for Signature on 22 March 1989, and entered into force on 5 May 1992. Of the 175 parties to the Convention, only Afghanistan, Haiti, and the United States have signed the Convention but not yet ratified it. ©navclasses
