UPSC Prelims 2017 · GS Paper I
Question 45: Science and Technology
With reference to agriculture in India, how can the technique of ‘genome sequencing’, often seen in the news, be used in the immediate future ?
- 1.Genome sequencing can be used to identify genetic markers for disease resistance and drought tolerance in various crop plants.
- 2.This technique helps in reducing the time required to develop new varieties of crop plants.
- 3.It can be used to decipher the host-pathogen relationships in crops.
Select the correct answer using the code given below :
AnswerUPSC’s answer is (d).
Sequencing a crop's genome shows which genes it carries, so breeders can find genetic markers linked to traits such as disease resistance and drought tolerance (Statement 1). Using such markers to select plants cuts the many years normally needed to breed a new variety (Statement 2). Comparing genomes of crops and pathogens also helps scientists understand host-pathogen interactions (Statement 3). All three are valid uses.
- 1. Genetic markers for disease resistance and drought tolerance can be identified.
- 2. Marker-based selection shortens the time to develop new varieties.
- 3. Genomic data helps decipher host-pathogen relationships.
How you could have got this
- If you were sure statement 1 is correct, (b) goes: it leaves 1 out.
What you needed to know: Genetic markers for disease resistance and drought tolerance can be identified.
- Then, if you were sure statement 2 is correct, (a) and (c) go: each of them leaves 2 out.
What you needed to know: Marker-based selection shortens the time to develop new varieties.
Only (d) is left. You didn’t need statement 3.
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) Incomplete: statements 2 and 3 are also valid.
- (b) Incomplete: statement 1 on genetic markers is also valid.
- (c) Incomplete: faster breeding (2) is also valid.
- (d) Right: all three are valid uses of genome sequencing.
Answer: UPSC’s key. Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 2017, General Studies Paper I, Series A. The paper on upsc.gov.in.