Natural Resources MCQ
1. The atmosphere of the earth is heated by radiations which are mainly
(a) radiated by the sun
(b) re-radiated by land
(c) re-radiated by water
(d) re-radiated by land and water
Ans. (d) re-radiated by land and water
Explanation: The hear from the sun reaches the earth and heats up the land and water. After that, heat from land and water is re-radiated to heat up the atmosphere.
2. If there were no atmosphere around the earth, the temperature of the earth will
(a) increase
(b) go on decreasing
(c) increase during day and decrease during night
(d) be unaffected
Ans. (c) increase during day and decrease during night Explanation: This is because of the atmosphere that the earth is saved from becoming too hot during day time. This happens because a significant amount of heat is prevented from reaching the earth’s surface by the atmosphere. Moreover, the atmosphere prevents the heat from escaping during night. Thus, an ambient temperature is maintained on the earth throughout the 24-hour period.
3. What would happen, if all the oxygen present in the environment is converted to ozone?
(a) We will be protected more
(b) It will become poisonous and kill living forms
(c) Ozone is not stable, hence it will be toxic
(d) It will help harmful sun radiations to reach earth and damage many life forms.
Ans. (b) It will become poisonous and kill living forms
Explanation: Living being need oxygen for respiration. Lack of oxygen will kill all living beings.
4. One of the following factors does not lead to soil formation in nature
(a) the sun
(b) water
(c) wind
(d) polythene bags
Ans. (d) polythene bags
Explanation: Polythene bags end up contaminating the soil and turning the soil barren
5. The two forms of oxygen found in the atmosphere are
(a) water and ozone
(b) water and oxygen
(c) ozone and oxygen
(d) water and carbon-dioxide
Ans. (c) ozone and oxygen
Explanation: Ozone is an allotrope of oxygen.
6. The process of nitrogen-fixation by bacteria does not take place in the presence of
(a) molecular form of hydrogen
(b) elemental form of oxygen
(c) water
(d) elemental form of nitrogen
Ans. (b) elemental form of oxygen
7. Rainfall patterns depend on
(a) the underground water table
(b) the number of water bodies in an area
(c) the density pattern of human population in an area
(d) the prevailing season in an area
Ans. (b) the number of water bodies in an area
Explanation: Water bodies provide water for evaporation. Water vapour, formed after evaporation condense to cause rainfall. Lack of water bodies in an area would reduce humidity in air and thus will adversely affect the rainfall.
8. Among the given options, which one is not correct for the use of large amount of fertilisers and pesticides?
(a) They are eco-friendly
(b) They turn the fields barren after some time
(c) They adversally affect the useful component from the soil
(d) They destroy the soil fertility
Ans. (a) They are eco-friendly
Explanation: Adverse effects mentioned in other options make the fertilizers and pesticides non-friendly to the ecosystem.
9. The nitrogen molecules present in air can be converted into nitrates and nitrites by
(a) a biological process of nitrogen fixing bacteria present in soil
(b) a biological process of carbon fixing factor present in soil
(c) any of the industries manufacturing nitrogenous compounds
(d) the plants used as cereal crops in field
Ans. (a) a biological process of nitrogen fixing bacteria present in soil
Explanation: Cereal crops themselves cannot fix nitrogen. They harbour nitrogen fixing bacteria in their root nodules. So, option (d) is incorrect. Factories cannot utilize nitrogen in the air to produce nitrogenous compounds; they use petrochemicals for this purpose. Hence, option (c) is incorrect. Option (b) talks about carbon fixation and hence is
incorrect.
10. One of the following processes is not a step involved in the water-cycle operating in nature
(a) evaporation
(b) transpiration
(c) precipitation
(d) photosynthesis
Ans. (d) photosynthesis
Explanation: Photosynthesis is involved in carbon cycle and not in water cycle.
11. The term “water-pollution” can be defined in several ways. Which of the following statements does not give the correct definition?
(a) The addition of undesirable substances to water-bodies
(b) The removal of desirable substances from water-bodies
(c) A change in pressure of the water bodies
(d) A change in temperature of the water bodies
Ans. (c) A change in pressure of the water bodies
Explanation: A change in pressure of the water bodies can happen because of physical causes and it does not result in contamination of water.
12. Which of the following is not a greenhouse gas?
(a) Methane
(b) Carbon dioxide
(c) Carbon monoxide
(d) Ammonia
Ans. (d) Ammonia
13. Which step is not involved in the carbon-cycle?
(a) Photosynthesis
(b) Transpiration
(c) Respiration
(d) Burning of fossil fuels
Ans. (b) Transpiration
Explanation: Transpiration is involved in water cycle and not in carbon cycle.
14. ‘Ozone-hole’ means
(a) a large sized hole in the ozone layer
(b) thinning of the ozone layer
(c) small holes scattered in the ozone layer
(d) thickening of ozone in the ozone layer
Ans. (b) thinning of the ozone layer
Explanation: Mention of the term ‘hole’ rules out options ‘a’ and ‘c’. Thickening is similar to strengthening and hence options ‘d’ is ruled out.
15. Ozone-layer is getting depleted because of
(a) excessive use of automobiles
(b) excessive formation of industrial units
(c) excessive use of man-made compounds containing both fluorine and chlorine
(d) excessive deforestation.
Ans. (c) excessive use of man-made compounds containing both fluorine and chlorine Explanation: Compounds which contains both fluorine and chlorine are called chlorofluorocarbons (CFCs). Chlorine and fluorine react with ozone to convert it into
oxygen and thus they result in depletion of ozone layer.
