2023 GS Paper I, all questions
UPSC Prelims 2023 · GS Paper I
Question 70: Science and Technology
'Microsatellite DNA' is used in the case of which one of the following?
aStudying the evolutionary relationships among various species of fauna
bStimulating 'stem cells' to transform into diverse functional tissues
cPromoting clonal propagation of horticultural plants
dAssessing the efficacy of drugs by conducting series of drug trials in a population
AnswerUPSC’s answer is (a).
Microsatellites are short, repeated DNA sequences that vary a lot between individuals and species. Because they mutate quickly and are inherited, they serve as markers for genetic diversity, population structure and evolutionary relationships among species, and for forensics and paternity tests. They are not used to turn stem cells into tissues, to clone plants, or to run drug trials.
Why each option is right or wrong
- (a) Correct: microsatellite markers help study relationships among species.
- (b) Directing stem cells into tissues uses growth factors and culture methods.
- (c) Clonal propagation uses tissue culture or cuttings.
- (d) Drug-efficacy trials use clinical studies, not DNA repeats.
Answer: UPSC’s key. Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 2023, General Studies Paper I, Series A. The paper on upsc.gov.in.