UPSC CSE Prelims
Science & Technology Previous Year Questions (PYQs)
Solved Previous Year Questions (PYQs) for Science & Technology in UPSC CSE Prelims in English & Hindi Medium.
Chapter Breakdown: Scroll →
Consider the following statements regarding: The Mangalyaan launched by ISRO
- is also called the Mars Orbiter Mission
- made India the second country to have a spacecraft orbit the Mars after USA
- made India the only country to be successful in making its spacecraft orbit the Mars in its very first attempt
Which of the statements given above is/are correct?
Detailed Explanation:
✅ Statement 1 – Correct: Mangalyaan is officially called the Mars Orbiter Mission (MOM), launched by ISRO in 2013.
❌ Statement 2 – Incorrect: India was the fourth space agency to reach Mars orbit, after the Soviet Union, NASA (USA), and the European Space Agency.
✅ Statement 3 – Correct: India became the first nation to successfully orbit Mars on its maiden attempt, a unique achievement as all previous Mars missions by other nations had failed in their first attempts.
In the context of the developments in bioinformatics, the term ‘transcriptome’, sometimes seen in the news, refers to -
Detailed Explanation:
The transcriptome refers to the complete set of RNA transcripts (especially mRNA molecules) produced by the genome of an organism under specific circumstances or in a specific cell.
Unlike the static genome, the transcriptome is dynamic and reflects which genes are actively being expressed at any given time, making it crucial for understanding gene regulation, cellular functions, and responses to environmental stimuli.
With reference to the use of nanotechnology in the health sector, which of the following statements is/are correct?
- Targeted drug delivery is made possible by nanotechnology
- Nanotechnology can largely contribute to gene therapy
Select the correct answer using the code given below.
Detailed Explanation:
✅ Statement 1 – Correct: Nanoparticles enable targeted drug delivery by carrying drugs directly to diseased cells, minimizing side effects and enhancing treatment efficacy.
✅ Statement 2 – Correct: Nanocarriers deliver genetic material (DNA/RNA) into specific cells, making nanotechnology crucial for gene therapy to treat genetic disorders.
🧐 Not Sure What to Study Next?
Get a personalised study plan based on your goals, time and revision needs.
With reference to ‘Near Field Communication (NFC) Technology’, which of the following statements is/are correct?
- It is a contactless communication technology that uses electromagnetic radio fields
- NFC is designed for use by devices which can be at a distance of even a metre from each other
- NFC can use encryption when sending sensitive information.
Select the correct answer using the code given below.
Detailed Explanation:
✅ Statement 1 – Correct: NFC (Near Field Communication) is a contactless communication technology that uses electromagnetic radio fields operating at 13.56 MHz frequency to enable data exchange between devices.
❌ Statement 2 – Incorrect: NFC is designed for very short-range communication, typically requiring devices to be within 4-10 cm (a few centimeters) of each other, not a metre. This short range is a deliberate security feature.
✅ Statement 3 – Correct: NFC supports encryption protocols and secure elements to protect sensitive data during transmission, making it suitable for contactless payments and secure access control applications.
In which of the following activities are Indian Remote Sensing (IRS) satellites used?
- Assessment of crop productivity
- Locating groundwater resources
- Mineral exploration
- Telecommunications
- Traffic studies
Select the correct answer using the code given below
Detailed Explanation:
✅ Statement 1 – Correct: IRS satellites use multispectral and hyperspectral imaging to monitor crop health, growth patterns, and productivity assessment through vegetation indices like NDVI.
✅ Statement 2 – Correct: Remote sensing data from IRS helps identify groundwater potential zones by analyzing geological structures, lineaments, and soil moisture patterns.
✅ Statement 3 – Correct: IRS satellites provide spectral signatures of surface minerals, aiding in mineral exploration and geological mapping through techniques like lithological discrimination.
❌ Statement 4 – Incorrect: Telecommunications require geostationary communication satellites (INSAT/GSAT series), not IRS (earth observation) satellites which are designed for remote sensing, not signal relay.
❌ Statement 5 – Incorrect: Traffic studies require high temporal resolution and real-time monitoring; IRS satellites have limited revisit times and are not optimized for dynamic traffic flow analysis.
In the context of modern scientific research, consider the following statements about ‘IceCube’, a particle detector located at the South Pole, which was recently in the news :
- It is the world’s largest neutrino detector, encompassing a cubic kilometre of ice.
- It is a powerful telescope to search for dark matter
- It is buried deep in the ice.
Which of the statements given above is/are correct?
Detailed Explanation:
✅ Statement 1 – Correct: IceCube is the world's largest neutrino detector, encompassing a cubic kilometre of ice at the South Pole.
✅ Statement 2 – Correct: It functions as a powerful telescope to search for dark matter and investigates high-energy cosmic phenomena involving black holes and neutron stars.
✅ Statement 3 – Correct: The detector is buried deep in the ice, extending from 1,450 to 2,450 meters below the surface to shield it from atmospheric interference and enhance precision.
Among the following which was frequently mentioned in the news for the outbreak of the Ebola virus recently?
Detailed Explanation:
The 2014–2016 Ebola outbreak was the most widespread epidemic of Ebola virus disease (EVD) in history, primarily affecting West African countries.
The outbreak began in Guinea in December 2013 and rapidly spread to neighboring Liberia and Sierra Leone, causing over 11,000 deaths and massive socio-economic disruption. These three countries accounted for the vast majority of cases and were frequently mentioned in global news coverage.
Which of the following statements is/are correct regarding National Innovation Foundation-India (NIF)?
- NIF is an autonomous body of the Department of Science and Technology under the Central Government
- NIF is an initiative to strengthen the highly advanced scientific research in India’s premier scientific institutions in collaboration with highly advanced foreign scientific institutions.
Select the correct answer using the code given below.
Detailed Explanation:
✅ Statement 1 – Correct: National Innovation Foundation-India (NIF) is an autonomous body under the Department of Science and Technology (DST), established in 2000 to strengthen grassroots innovation ecosystem.
❌ Statement 2 – Incorrect: NIF focuses on grassroots innovations, traditional knowledge, and solutions by common people (farmers, artisans, students), not on advanced scientific research in premier institutions or foreign collaborations. It scouts, documents, and supports community-level innovations.
The term ‘Goldilocks Zone’ is often seen in the news in the context of
Detailed Explanation:
Goldilocks Zone (also called habitable zone) is the region around a star where conditions are just right for liquid water to exist on a planet's surface.
Astronomers use this concept to search for Earth-like exoplanets that could potentially harbor life, making option 3 correct.
H1N1 virus is sometimes mentioned in the news with reference to which one of the following diseases?
Detailed Explanation:
H1N1 virus is a subtype of Influenza A virus that causes Swine flu, which was declared a pandemic by WHO in June 2009.
The virus contains glycoproteins haemagglutinin (H) and neuraminidase (N), hence named H1N1, and was also responsible for the 1918 Spanish Flu outbreak.
The Genetic Engineering Appraisal Committee is constituted under the
Detailed Explanation:
Genetic Engineering Appraisal Committee (GEAC) is constituted under the Environment Protection Act, 1986 through the Rules for Manufacture, Use, Import, Export and Storage of Hazardous Microorganisms/Genetically Engineered Organisms or Cells, 1989.
GEAC functions as the apex body in the Ministry of Environment, Forest and Climate Change for appraisal of activities involving release of genetically engineered organisms and products into the environment, including experimental field trials.
Which of the following has/have been accorded “Geographical Indication” status?
- Banaras Brocades and Sarees
- Rajasthani Dal-Bati-Churma
- Tirupati Laddu
Select the answer using the code given below:
Detailed Explanation:
✅ Statement 1 – Correct: Banaras Brocades and Sarees were granted GI status in 2009, recognizing the unique handloom weaving traditions of Varanasi, Uttar Pradesh.
❌ Statement 2 – Incorrect: Rajasthani Dal-Bati-Churma has not been accorded GI status, though it is a famous traditional food of Rajasthan.
✅ Statement 3 – Correct: Tirupati Laddu, the sacred prasad of Tirumala Venkateswara Temple, Andhra Pradesh, received GI status in 2009 to protect its unique recipe and reputation.
With reference to Agni-IV Missile, which of the following statements is/are correct?
- It is a surface-to-surface missile.
- It is fuelled by liquid propellant only.
- It can deliver one-tonne nuclear warheads about 7500 km away.
Select the correct answer using the code given below.
Detailed Explanation:
✅ Statement 1 – Correct: Agni-IV is a surface-to-surface ballistic missile designed to be launched from mobile land-based platforms and strike ground targets.
❌ Statement 2 – Incorrect: Agni-IV uses two-stage solid-fuel propulsion, not liquid propellant. Solid propellants provide better storage stability and quick launch capability.
❌ Statement 3 – Incorrect: Agni-IV has a range of approximately 4,000 km, not 7,500 km. While it can carry a one-tonne payload, the 7,500 km range figure is incorrect.
Consider the following diseases
- Diphtheria
- Chickenpox
- Smallpox
Which of the above diseases has/have been eradicated in India?
Detailed Explanation:
❌ Statement 1 – Incorrect: Diphtheria has not been eradicated; India still administers the Pentavalent vaccine (introduced in 2011–12) which includes DPT (Diphtheria, Pertussis, Tetanus) component, indicating ongoing disease burden.
❌ Statement 2 – Incorrect: Chickenpox (Varicella) remains endemic in India; the Varicella vaccine is available but not part of the Universal Immunization Programme (UIP), and cases occur regularly across the country.
✅ Statement 3 – Correct: Smallpox was declared eradicated from India in 1975 (last case in 1975), and WHO certified global eradication in 1980; India played a key role in the worldwide eradication campaign.
Consider the following techniques/phenomena:
- Budding and grafting in fruit plants
- Cytoplasmic male sterility
- Gene silencing
Which of the above is/are used to create transgenic crops?
Detailed Explanation:
❌ Statement 1 – Incorrect: Budding and grafting are traditional vegetative propagation techniques that multiply plants asexually without altering DNA; no recombinant DNA technology is used, so they do not create transgenic crops.
✅ Statement 2 – Correct: Cytoplasmic male sterility (CMS) can be manipulated through genetic engineering to introduce or transfer sterility genes into crops, creating transgenic lines for hybrid seed production.
✅ Statement 3 – Correct: Gene silencing (RNA interference/RNAi) uses engineered genetic constructs to suppress specific gene expression in plants, making it a key technique for developing transgenic crops with desired traits.