Question
Which of the following is an innovative remedy for plastic waste? [NEET (Odisha) 2019]
(a) Buming in the absence of axygen
(b) Burrying $500 \mathrm{~m}$ deep below soi surtace
(c) Polyblend
(d) Electrostatic precipitator
Answer/Explanation
Ans. (c)
Polyblend is an innovative remedy for plastic waste. Polyblend is a fine powder of recycled modified plastic which when mixed with bitumen, can be used to lay roads.
Question
Which of these following methods is the most suitable for disposal of nuclear waste? [NEET (National) 2019]
(a) Bury the waste under Antarctic ice-caver
(b) Dump the waste within rocks under deep ocean
(c) Bury the waste within rocks deep below the Earth’s surface
(d)Shoot the waste into space
Answer/Explanation
Ans. (c)
Nuclear waste is usually disposed by burying it within rocks deep below the earth’s surface. Nuclear waste disposal is extremely hazardous. Before burrying the waste, it is sealed in large containers so as to reduce its radiation effects.
Question
Relative Biological Effectiveness (RBE) is usually referred to damages caused by [CBSE AIPMT 2000]
(a) low temperature
(b) high temperature
(c)encephalitis
(d) radiation
Answer/Explanation
Ans. (d)
RBE(Relative Bialogical Effectiveness) is a comparison of the dase of the radiation being studied with the dose of standard radiation producing the same effect.
Question
If by radiation all nitrogenase enzymes are inactivated, then there will be no [CBSE AIPMT 2004]
(a) foxation of nitrogen in legumes
(b) fixation atmospheric nitrogen
(c) conversion from nitfate to nitrite in legumes
(d) conversion from ammanium to nitrate in soil
Answer/Explanation
Ans. (a)
The enzyme nitrogenase is required for the process of biological nitrogen focation only. Foxation of atmospheric nitrogen accur through other route also. Neither nitrification (comversion at ammanium to nitrate) nof conversion of nitrate to nittrite require nitrogenase.
Question
Relative Biological Effectiveness (RBE) usually refers to the damages caused by [CBSE AIPMT 2000]
(a) low temperature
(b) high temperature
(c) radiation
(d) pollution
Answer/Explanation
Ans. (c)
RBE (Relative Bialogical Effectiveness) is a comparison af the dose of radiation being studied with the dose of standard radiation producing the same effect.
Question
The supersonic jets cause pollution by the thinning of [CBSE AIPMT 1998]
(a) $\mathrm{CO}_2$ layer
(b) $\mathrm{SO}_2$ layer
(c) $0_2$ layer
(d) $0_3$ layer
Answer/Explanation
Ans. (d)
Ozone layer is found in the stratosphere. It protects us from the harmful UV radiations coming from the sun. The supersonic aircrafts flying at stratospheric heights cause major disturbances in ozone level due to release of CFCs which react with $\mathrm{O}_3$ present there, thus cause thinning of $\mathrm{O}_3$ layer.
Question
The worst environmental hazards were created by accidents in nuclear power plant and MIC gas tragedy respectively in [CBSE AIPMT 1996]
(a) Russia in 1990 and Bhopal in 1986
(b) Ukrain in 1988 and USA in 1984
(c) Bhopal in 1984 and Russia in 1990
(d) Ukrain in 1986 and Bhopal in 1984
Answer/Explanation
Ans. (d)
Worst environmental hazards were in Ukrain in 1986 and MIC gas tragedy in Bhopal in 1984.
Question
Most hazardous metal pollutant of automobile exhausts is [CBSE AIPMT 1992]
(a) mercury
(b) cadmium
(c) lead
(d) copper
Answer/Explanation
Ans. (c)
Lead particles are found in the smoke from automobiles which cause nervous disorder in man.
Question
Pedology is science of [CBSE AIPMT 1991]
(a) earth
(b) soil
(c) diseases
(d) pollution
Answer/Explanation
Ans. (b)
Pedology is the study of soil and soil properties.