UPSC Prelims 2014 · GS Paper I
Question 98: Science and Technology
There is some concern regarding the nanoparticles of some chemical elements that are used by the industry in the manufacture of various products. Why?
- 1.They can accumulate in the environment, and contaminate water and soil.
- 2.They can enter the food chains.
- 3.They can trigger the production of free radicals.
Select the correct answer using the code given below.
AnswerUPSC’s answer is (d).
Engineered nanoparticles of elements such as silver, zinc oxide and titanium dioxide are used in many products, and they raise health and environmental concerns. They can accumulate in the environment and contaminate water and soil, can enter food chains, and can trigger the production of free radicals that damage cells. So all three statements describe real concerns.
- 1. Nanoparticles can persist and contaminate water and soil.
- 2. They can enter and move up food chains.
- 3. They can trigger free radical production.
How you could have got this
- If you were sure statement 2 is correct, (b) and (c) go: each of them leaves 2 out.
What you needed to know: They can enter and move up food chains.
- Then, if you were sure statement 3 is correct, (a) goes: it leaves 3 out.
What you needed to know: They can trigger free radical production.
Only (d) is left. You didn’t need statement 1.
Which options go is worked out from UPSC’s key and the options, not by a model.
Why each option is right or wrong
- (a) Wrong. Free-radical production is also a concern.
- (b) Wrong. Accumulation and food chain entry are also concerns.
- (c) Wrong. Entry into food chains is also a concern.
- (d) Right. All three are concerns about nanoparticles.
Answer: UPSC’s key. Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 2014, General Studies Paper I, Series A. The paper on upsc.gov.in.