ECOLOGY
ORGANISMS AND THE ENVIRONMENT
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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It encourages excessive plant growth
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It contains heavy metals which build up in the tissues of living organisms.
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It is not biodegradable
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It depletes the oxygen levels in the water
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Detailed explanation-1: -Potential toxins on organisms may be compartmentalised into insoluble deposits; thus, this prevents any interactions with essential biochemical reactions that occur in the cytoplasm. Since metals are non-biodegradable and hence remain persistent in the environment for a very long time, they cannot be broken down.
Detailed explanation-2: -Heavy metals disrupt metabolic functions in two ways: They accumulate and thereby disrupt function in vital organs and glands such as the heart, brain, kidneys, bone, liver, etc. They displace the vital nutritional minerals from their original place, thereb, hindering their biological function.
Detailed explanation-3: -In addition, these metals are toxic and carcinogenic. They cause serious problems for aquatic ecosystems and especially humans. Different methods have been utilized to remove heavy metals from the wastewater, such as membrane filtration, adsorption, and ion exchange.
Detailed explanation-4: -Being persistent pollutants, heavy metals accumulate in the environment and consequently contaminate the food chains. Accumulation of potentially toxic heavy metals in biota causes a potential health threat to their consumers including humans.
Detailed explanation-5: -Sources of heavy metals include mining, industrial production (foundries, smelters, oil refineries, petrochemical plants, pesticide production, chemical industry), untreated sewage sludge and diffuse sources such as metal piping, traffic and combustion by-products from coal-burning power stations.