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 & explanation
Answer: (c) 1 and 3 only
Bioremediation speeds up the natural breakdown of pollutants by microbes, and microbes can be genetically engineered for the job. But microbes break down organic compounds; metals such as cadmium and lead are elements that cannot be degraded, only changed in form or immobilised, so statement 2 overclaims.
- ✓ 1. It uses microorganisms that feed on or co-metabolise contaminants, boosting the same biodegradation that happens in nature by supplying nutrients, oxygen or other electron acceptors.
- ✗ 2. Bioremediation is described as degrading organic contaminants. Heavy metals cannot be broken down by microbes, so 'readily and completely treated' is wrong; at best microbes change their chemical form.
- ✓ 3. Biotechnology uses genetically modified microbes for bioremediation; in 1971 Ananda Mohan Chakrabarty developed a bacterium that could break down oil spills.
Remember · Bioremediation = microbes degrading organic pollutants (oil, solvents, pesticides); engineered microbes help. Heavy metals cannot be degraded, only transformed or immobilised.
📘 Read it in NCERT: Class 12 Biology, Ch 10 (practise this chapter) · Class 8 Curiosity, Ch 2 (practise this chapter)
Sources
- US EPA, CLU-IN: Bioremediation Overview ↗ · reference work “Bioremediation uses microorganisms to degrade organic contaminants in soil, groundwater, sludge, and solids. The microorganisms break down contaminants by using them as an energy source or cometabolizing them with an energy source.”
- NCERT Class 12 · Biology, Chapter 10 “using genetically modified microbes, fungi, plants and animals. The applications of biotechnology include therapeutics, diagnostics, genetically modified crops for agriculture, processed food, bioremediation, waste treatment, and energy production.”
- NCERT Class 8 · Curiosity, Chapter 2 “In 1971, he developed a special bacterium that could break down oil spills, helping to clean the environment.”
Question and answer: UPSC's official GS Paper I (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). ·