UPSC Mains 2025 Revision Checklist: Top 15 Science and technology topics aspirants shouldn't miss

Indian Express

2 days ago

Are You Mains Ready? The UPSC Civil Services Mains Examination 2025 will start from August 22. No subject is predictable — each one can throw in unexpected topics when you least expect them. Science and Technology stands out in General Studies-Paper III as a rapidly growing section in which conceptual depth must coexist with knowledge of the most recent discoveries and breakthroughs.
From AI and quantum technologies to space missions, biotechnology, and renewable energy solutions, this domain frequently overlaps with security, the environment, the economy, and government, making regular updates and interdisciplinary collaboration critical for success.
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Recently, the Department of Biotechnology (DBT) has made the genome data of 10,000 individuals publicly accessible under the Genome India Project (GIP). It is essential to recognise how creating a comprehensive genetic database can revolutionise precision medicine, enhance diagnostics, and facilitate population-specific disease risk prediction—crucial for India's diverse genetic landscape.
Key dimensions to cover:
• What is genome sequencing?
• What is the strategic importance of GIP?
• What are the ethical and technical challenges?
• How would this project help to advance personalised medicine and public health in the country?
• How can genome mapping contribute to rare disease diagnosis in India?
• What are the potential non-medical applications of genome data in India?
• How does GIP help in shaping public health policies for India?
PYQ Insight:
📍What is the basic principle behind vaccine development? How do vaccines work? What approaches were adopted by the Indian vaccine manufacturers to produce COVID-19 vaccines? (2022)
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Why the Genome India Project and Gene Editing are important for the UPSC Exam
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Recently, the Indian Navy commissioned INS Nistar. The induction of Nistar into the Navy after the successful integration of the two DSRVs is a major milestone for India's deep-sea capabilities. In the context of the Indian Ocean Region (IOR), it is important from a GS-3 security and maritime security perspective.
Key dimensions to cover:
• What is the IOR's role in securing India's energy security?
• How does SAGAR reflect India's maritime security and foreign policy objectives?
• What are the main global trade routes in IOR?
• In what ways has the Indian Navy helped with humanitarian aid and disaster relief in the IOR?
• What is the role of IONS, IORA, and the QUAD in maritime cooperation?
• What role can the Indian Coast Guard and radar networks play in improving coastal security integration?
PYQ Insight:
📍What are the maritime security challenges in India? Discuss the organisational, technical and procedural initiatives taken to improve maritime security. (2022)
Other important article covering the same topic
How newly commissioned INS Nistar will help save lives in deep sea
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📌 Why in News?
The much-awaited launch of NISAR — an earth observation satellite jointly developed by NASA and ISRO was launched from the country's only spaceport in Sriharikota, Andhra Pradesh. NISAR is the first of its kind mission, jointly developed by ISRO and NASA. NISAR, which stands for NASA-ISRO Synthetic Aperture Radar, has been built by space agencies of the US and India under a partnership agreement signed in 2014. ISRO's recent space missions are crucial for UPSC Mains GS-3 because they demonstrate India's accomplishments in science and technology, strategic capabilities, disaster management, and space diplomacy.
Key dimensions to cover:
• How is the NISAR mission in strengthening India's disaster management, environmental monitoring, and climate resilience strategies?
• Read about India's first human spaceflight programme.
• How ISRO's SpaDeX mission marks a technological milestone for India's future lunar and space station ambitions?
• How does the upgradation of the NavIC navigation system through the NVS-02 satellite contribute to India's strategic and civilian applications?
• Read about Aditya-L1 (Solar Observation Mission)
• What is microgravity research in space?
PYQ Insight:
📍What is the main task of India's third moon mission which could not be achieved in its earlier mission? List the countries that have achieved this task. Introduce the subsystems in the spacecraft launched and explain the role of the Virtual Launch Control Centre' at the Vikram Sarabhai Space Centre which contributed to the successful launch from Sriharikota. (2023)
📍What do you understand by 'Standard Positioning System' and 'Precision Positioning System' in the GPS era? Discuss the advantages India perceives from its ambitious IRNSS programme employing just seven satellites. (2015)
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Knowledge Nugget | NISAR in focus: Why is this NASA-ISRO mission relevant for UPSC Exam
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📌 Why in News?
The clinical trial results of India's first CAR T-cell therapy, published in The Lancet, show that it worked for nearly 73 per cent of patients. In 2017, a similar question was asked: Stem cell therapy is gaining popularity in India to treat a wide variety of medical conditions including Leukaemia, Thalassemia, damaged cornea and several burns. Describe briefly what stem cell therapy is and what advantages it has over other treatments? Therefore, it becomes essential to cover such topics.
Key dimensions to cover:
• What is CAR T-cell therapy?
• Working principle of CAR T-cell therapy
• Its applications, advantages and challenges
• What are its implications for India's health security and innovation ecosystem?
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CAR-T cell therapy: What is it and how does it work
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In a milestone for ISRO, the cowpea seedlings it sent to space as part of a biological experiment on December 30 have sprouted their first leaves. The experiment, ISRO's first biological experiment in space, was part of CROPS (Compact Research Module for Orbital Plant Studies), an automated platform designed to cultivate and sustain plant life in the microgravity environment of space.
Key dimensions to cover:
• What is the CROPS (Compact Research Module for Orbital Plant Studies) mission?
• What is the significance of developing plant cultivation systems in microgravity for future space missions?
• What are the potential benefits of space-based agriculture for long-duration human space exploration and settlements?
• How can advancements in plant growth research in space contribute to food security and life-support systems on Earth?
• What is the scope of microgravity plant research in enhancing the nation's space capabilities?
PYQ Insight:
📍Discuss India's achievements in the field of Space Science and Technology. How the application of this technology has helped India in its socio-economic development? (2016)
Other important article covering the same topic
How and why are plants grown in space: Takeaways from ISRO's success
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Following more than three years of arduous negotiations, member states of the World Health Organization (WHO) adopted a legally binding treaty designed to tackle future pandemics better. The pandemic treaty, which has been adopted without the United States, is the only the second legally binding accord in the WHO's 75-year history, the first being the 2003 tobacco control treaty.
Key dimensions to cover:
• What is the Global Pandemic Treaty?
• What are the key provisions of the treaty?
• How does the Global Pandemic Treaty seek to preserve national sovereignty while ensuring global cooperation?
• How far can the provisions of this treaty ensure preparedness for future pandemics?
PYQ Insight:
📍Critically examine the role of WHO in providing global health security during the Covid-19 pandemic. (2020)
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📌 Why in News?
Prime Minister Narendra Modi inaugurated three PARAM Rudra supercomputers worth Rs 130 crore. Developed indigenously under the National Supercomputing Mission (NSM), the three new supercomputers are located in Pune, Delhi, and Kolkata, and make up a High-Performance Computing (HPC) system tailored for weather and climate research.
Key dimensions to cover:
• What is a supercomputer?
• What is the National Supercomputing Mission?
• What is the significance of the National Supercomputing Mission?
• What is the role of the National Supercomputing Mission in strengthening India's research ecosystem in areas like climate modelling, drug discovery, and artificial intelligence?
• How does the National Supercomputing Mission contribute to India's aspirations in emerging technologies like quantum computing, big data analytics, and machine learning?
• Read about India's progress under the National Supercomputing Mission.
Other important article covering the same topic
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The United Nations' Outer Space Treaty is an international agreement binding member states to only use outer space for peaceful purposes. It spells out the principles governing the activities of states in the exploration and use of outer space, including the Moon and other celestial bodies. Russia vetoed a UN Security Council resolution, proposed jointly by the United States and Japan, which called on countries to prevent an arms race in outer space.
Key dimensions to cover:
• What is the Outer Space Treaty?
• What are its key provisions and relevance in the present era of commercial and military space activities?
• What is the role of the Outer Space Treaty in addressing issues of space debris management, satellite collisions, and the sustainability of outer space activities?
• What is the relevance of the Outer Space Treaty for India's space programme in the context of the Artemis Accords and emerging international space partnerships?
PYQ Insight:
📍Discuss India's achievements in the field of Space Science and Technology. How the application of this technology has helped India in its socio-economic development? (2016)
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In response to an increase in encounters with foreign terrorists in Jammu and Kashmir, the government is establishing an electronic surveillance system along its border with Pakistan to prevent infiltration. According to sources, this surveillance system consists of an integrated network of human-detection radars, thermal imaging and high-resolution cameras, complete floodlighting along fences, technology-enabled riverine patrols, and seismic sensors to locate tunnels.
Key dimensions to cover:
• What are advanced surveillance technologies?
• What is the role of facial recognition systems, biometric databases, and drone-based monitoring in law enforcement?
• What are the implications of advanced surveillance technology for disaster management, urban planning, and public health monitoring?
• How can India achieve a balance between technical advances in surveillance and the principles of transparency, accountability, and proportionality?
• How are advanced surveillance technologies becoming a strategic asset in modern warfare and counter-terrorism?
PYQ Insight:
📍India has a long and troubled border with China and Pakistan fraught with contentious issues. Examine the conflicting issues and security challenges along the border. Also give out the development Programme (BADP) and Border Infrastructure and Management (BM) Scheme. (2024)
📍The use of unmanned aerial vehicles (UAVs) by our adversaries across the borders to ferry arms/ammunitions, drugs, etc., is a serious threat to the internal security. Comment on the measures being taken to tackle this threat. (2023)
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In one of the biggest moves to expand nuclear energy sector, the government in Union Budget 2025 announced a Nuclear Energy Mission for research & development of Small Modular Reactors (SMRs) and set a target of operationalising at least five such reactors in the next eight years. Topics such as Small Modular Reactors (SMRs) are relevant as they cover clean energy transition, technological advancements, energy security, and policy reforms in India's nuclear sector.
Key dimensions to cover:
• What are SMRs?
• What are the design features and advantages of SMR?
• What are its potential role in India's energy transition?
• What are the implications of Small Modular Reactors for nuclear waste management and non-proliferation obligations?
• India's readiness in terms of R&D, manufacturing capacity, and policy framework for adopting Small Modular Reactor technology.
PYQ Insight:
📍Give an account of the growth and development of nuclear science and technology in India. What is the advantage of fast breeder reactor programme in India? (2017)
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The widespread misuse of deepfakes made the fight against misinformation more difficult. From time to time, various deepfake videos of actors and politicians have gone viral and have flared the issue of misinformation more widely. Thus, it becomes important to understand the issue of deepfakes from a broader perspective.
Key dimensions to cover:
• What are deepfakes and how do we identify them?
• What are the concerns associated with the deepfakes?
• What are the global initiatives related to deepfakes?
• What initiatives are taken by India to regulate deepfakes?
• What measures should be taken to combat the misuse of deepfakes and ensure digital trust?
• What is Artificial Intelligence (AI)?
• Benefits and Challenges of AI.
PYQ Insight:
📍Introduce the concept of Artificial Intelligence (AI). How does Al help clinical diagnosis? Do you perceive any threat to privacy of the individual in the use of AI in healthcare? (UPSC CSE 2023)
Other important article covering the same topic:
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Disagreements over sensitive sectors such as agriculture and dairy have added to the uncertainty of an interim trade deal between India and the United States. As US negotiators are turning up the heat, urging India to open its agriculture market to genetically modified (GM) crops, India has been resisting US demands for greater access in the agriculture and dairy sectors and accepting GM imports. In this context, it becomes important to know about the GM crops — understanding the underlying technology, their potential benefits, and the broader concerns associated with them.
Key dimensions to cover:
• What are genetically modified (GM) crops, and how are GM different from genetic editing?
• What is the current status of GM crop cultivation in India, and how is it regulated?
• What are the benefits of GM crops?
• What are the major concerns associated with GM crops?
• How is Gene Modification different from Gene Editing?
PYQ Insight:
📍How can biotechnology help to improve the living standards of farmers? (UPSC CSE 2019)
Other important article covering the same topic:
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A groundbreaking new study published in the Lancet warns that antimicrobial-resistant (AMR) pathogens could kill over 39 million people by 2050. The World Health Organization also published its first-ever guidance on antibiotic pollution from manufacturing ahead of the UN General Assembly High-Level Meeting on antimicrobial resistance. In this context, understanding the threat of antimicrobial resistance from a broader perspective becomes important.
Key dimensions to cover:
• What is antimicrobial resistance (AMR)?
• Why is AMR a global concern?
• What are the key factors contributing to the rise of AMR in India?
• How do superbugs evolve?
• What is the impact of AMR?
• What initiatives has the Government of India undertaken to combat AMR?
• What initiatives have been taken on the global level to address the challenge of increasing AMR?
• What steps should be taken to address the challenge of AMR in India?
PYQ Insight:
📍Can overuse and free availability of antibiotics without Doctor's prescription, be contributors to the emergence of drug-resistant diseases in India? What are the available mechanisms for monitoring and control? Critically discuss the various issues involved. (UPSC CSE 2014)
Other important article covering the same topic:
UPSC Issue at a Glance | Antimicrobial Resistance and India
📌 Why in News?
After spending 18 days on the International Space Station and orbiting around the Earth 288 times, Indian astronaut Group Captain Shubhanshu Shukla and his three colleagues on the Axiom-4 mission splashed down in the Pacific Ocean on 15th July after a 20-hour journey from the International Space Station (ISS). This mission not only strengthens India's foray into human spaceflight but also showcases its growing contribution to space research through a series of significant experiments led by Shukla aboard the ISS.
Key dimensions to cover:
• What is the Axiom-4 mission?
• What is the significance of the Axiom-4 mission for India?
• What is the significance of the International Space Station (ISS)?
• What is the Gaganyaan mission?
• What is India's roadmap for setting up the Bharatiya Antariksha Station?
• How does the Indian space sector benefit from private-sector participation?
• How is Shukla's experience going to help India in future space missions?
• How is India planning to exploit the space market?
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Knowledge Nugget: Axiom-4 mission — What you must know for UPSC Exam
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Health and government policies related to it are crucial components of the UPSC CSE syllabus. Additionally, the UPSC frequently includes questions on health and associated policies in its examinations. For example, in 2020, the UPSC asked questions about geriatric and maternal healthcare. Similarly, in 2018, there was a question regarding community-level healthcare interventions aimed at achieving 'Health for All.' In this context, knowing about the
Key dimensions to cover:
• What are rare diseases?
• How are rare diseases classified in India?
• What is the policy framework for rare diseases in India?
• What challenges are faced in diagnosing and treating rare diseases?
• How can India enhance its response to rare diseases?
PYQ Insight:
📍Appropriate local community-level healthcare intervention is a prerequisite to achieve 'Health for All' in India. Explain. (UPSC CSE 2018)
📍'Besides being a moral imperative of a Welfare State, primary health structure is a necessary precondition for sustainable development.' Analyse. (UPSC CSE 2021)
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Treatment of rare diseases: India must incentivise indigenous innovation and production
Issues in the treatment of 'rare diseases', and what the govt can do
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