181. Lincoln index measures
(a) Population mortality rate
(b) Population natality rate
(c) Population size
(d) Population density
Ans. d
182. Allelopathy refers to
(a) Inhibition of growth of one species by another by the production of toxins
(b) Inhibition of sporulation of pathogen by the host
(c) Altering the reproductive cycle of one organism by another
(d) Inhibition of growth of one species by another by preventing reproduction
Ans. a
183. The ratio between energy flow at different points in a food chain is known as
(a) Ecological capacity
(b) Ecological efficiency
(c) Ecological assimilation
(d) Ecological potential
Ans. b
184. Contamination of water with sewage is indicated by cysts of
(a) Escherichia
(b) Escherichia coli
(c) Pseudomonas
(d) Leishmania
Ans. b
185. Ultraviolet radiations from sunlight causes a reaction that produces
(a) fluorides
(b) carbon monoxide
(c) sulphur dioxide
(d) ozone
Ans. d
186. The ability of a population to increase under ideal environmental conditions is called
(a) Natality
(b) Carrying capacity
(c) Biotic potential
(d) Absolute natality
Ans. c
187. In an ecosystem, the energy flow is always
(a) Always unidirectional
(b) Always bidirectional
(c) In any direction
(d) Always down directional
Ans. a
188. In thermal stratification, the middle region which shows vertical temperature change is called
(a) Mesolimnion
(b) Epilimnion
(c) Metalimnion
(d) Hypolimnion
Ans. c
189. Select a non-denitrifying bacteria
(a) Pseudomonas aeruginosa
(b) Thiobacillus
(C) Thiobacillus denitrificans
(d) Bacillus ramosus
Ans. d
190. Which one is a ‘K’ selected species?
(a) Aspergillus
(b) Human
(c) Taraxacum
(d) Grass
Ans. b
191. DDT is a
(a) Green house gas
(b) Non-degradable pollutant
(c) Degradable pollutant
(d) None of these
Ans. b
192. Escherichia coli used as an indicator organism to determine pollution of water with
(a) Industrial effluents
(b) Heavy metals
(c) Pollen of aquatic plants
(d) Faecal matter
Ans. d
193. Eutrophication is often seen in
(a) Mountains
(b) Deserts
(c) Fresh water lakes
(d) Ocean
Ans. c
194. Biosphere is the
(a) envelope of gases surrounding the earth.
(b) the outermost layer of earths crust.
(c) the thin layer of organic matter containing all living things on the surface of the earth.
(d) None of the above.
Ans. c
195. The Earth Summit at Rio de Janeiro was held with the aim of integrating environmental imperatives with developmental aspirations in
(a) June 1972
(b) December 1972
(c) December 1993
(d) June 1993
Ans. a
196. The Global Action Plan adopted at Earth Summit held at Rio de Janeiro in June 1972 is also known as
(a) Agenda 20.
(b) Agenda 22.
(c) Agenda 23.
(d) Agenda 21
Ans. d
197. Fluoride pollution mainly affects
(a) Brain
(b) Teeth
(c) Heart
(d) Kidney
Ans. b
198. Gas leaked during Bhopal tragedy was
(a) Ethyl isothiocyanate
(b) Sodium ishothiocyanate
(c) Potassium isothiocyanate
(d) Methyl isocyanate
Ans. d
199. Environmental degradation is due to
(a) Rapid industrialization
(b) Onset of different development works
(c) Fast urbanization leading to deforestation
(d) All of the above
Ans. d
200. Behavioural disorders, development of destructive nature in later stages and neurotic traits as adults are the outcome of
(a) noise pollution
(b) thermal pollution
(c) radiation pollution
(d) soil pollution
Ans. a