Last seen: Oct 19, 2020
(a) If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion. Explanation: DDT (dichloro diphenyl trichlo...
(c) If the Assertion is correct but Reason is incorrect. Explanation: Organochlorine are persistent pesticides (e.g. DDT) which pass into food cha...
(a) If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion. Explanation: Sound level of jet aeroplanes ...
(a) 350; 150 Explanation: The Govt. of India through a new auto fuel policy has laid out a roadmap to cut down the vehicular pollution in Indian c...
(b) B has higher rate of oxygen dissolution. Explanation: Lake A and B are identical in all aspects except that Lake A has higher temperature. On ...
(d) liposoluble Explanation: DDT residues are rapidly passed through food chain causing biomagnification because DDT is soluble in lipids. Biomagn...
(c) 1 and 3 Explanation: Lots of urea and phosphate fertilizer were used in the crops in the vicinity and the lake water turned green and stinky. ...
(a) CO2 and CH4 Explanation: The gases that makes highest relative contribution to the green house gases are carbon dioxide (CO2) and methane (CH4...
(c) Solar energy - green house effect Explanation: Solar energy coming to the earth is not responsible for green house effect. It is the increase ...
(a) The greater the BOD of waste water, more is its polluting potential.
(c) Both (a) and (b) Explanation: In the environment, ozone is known for its both harmful and useful effects. Ozone present in stratosphere is use...
(a) DDT is a non-biodegradable pollutant Explanation: Excess fluorine in drinking water causes hardening of bones and stiffness of joints, black f...
(c) Snake Explanation: Biomagnification is phenomenon of increasing concentration of a compound in the tissues of chain, usually as a result of fo...
(b) 20-25 km Explanation: Stratosphere extends from 20-25 km above tropospheres. It is also called ozonosphere due to presence of ozone. Temperatu...
(b) Blue baby disease (methaemoglobinaemia) due to heavy use of nitrogen rich fertilizers in the area. Explanation: Blue baby disease is caused by...
(c) vermiculture Explanation: Vermiculture means artificial seating of worms whose excreta is rich in humus. These worms eat farmyard manure along...
(b) excess of nitrates in drinking water Explanation: Excess nitrate in drinking water, leaves and fruits, changes into nitrite in alimentary cana...
(a) photochemical smog Explanation: Nitrogen oxides form peroxyacyl nitrate (PAN) by reacting with hydrocarbons. It leads to photochemical smog fo...
(c) death of fish due to lack of oxygen Explanation: A lake rich in (domestic sewage) nutrients accelerates the growth of algae which use oxygen a...
(c) release of industrial waste containing mercury in fishing water Explanation: Mercury compounds in waste water are converted by bacterial actio...