Q89.
In the context of solving pollution problems, what is/are the advantage/advantages of bioremediation technique? 1. It is a technique for cleaning up pollution by enhancing the same biodegradation process that occurs in nature. 2. Any contaminant with heavy metals such as cadmium and lead can be readily and completely treated by bioremediation using microorganisms. 3. Genetic engineering can be used to create microorganisms specifically designed for bioremediation. Select the correct answer using the code given below:
Answer
C
Explanation
Statement 1 is correct. Bioremediation is treatment that uses naturally occurring organisms to break down hazardous substances into less toxic or non-toxic substances, enhancing the natural biodegradation process. Statement 2 is not correct. Not all contaminants are easily treated by bioremediation using microorganisms — heavy metals such as cadmium and lead are not readily absorbed or captured by microorganisms. Statement 3 is correct. For example, bacterium Deinococcus radiodurans (the most radioresistant organism known) has been modified to consume and digest toluene and ionic mercury from highly radioactive nuclear waste.