Miscellaneous: UPSC Previous Year Questions (Science and Technology)
68 previous year UPSC Prelims questions on applied science and technology appear here, from 2011 to 2025. This is the second-largest chapter and groups energy, vehicles, materials and everyday technology. The 2025 paper asked about alternative powertrain vehicles, EV battery elements, coal gasification and rare earth elements. The explanations name the technology and its use.
Explanations state facts as of the year each question was asked; words like “recently” refer to that year.
Showing 21–30 of 68 questions
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UPSC 2020Science and Technology · Miscellaneous
Q21. Which of the following statements are correct regarding the general difference between plant and animal cells? 1. Plant cells have cellulose cell walls whilst animal cells do not. 2. Plant cells do not have plasma membranes unlike animal cells which do. 3. Mature plant cell has one large vacuole whilst an animal cell has many small vacuoles. Select the correct answer using the code given below:
Explanation
Statement 1 is correct: Both plants and animals contain eukaryotic cells, their cell structures are quite similar. The plasma membrane, nucleus, cytoplasm, ribosomes, and mitochondria in general make up each eukaryotic cell. The plant cell differs significantly from other cells in that it has a hard cell wall surrounding it. While the cells of other species are surrounded by a cell wall, cellulose and proteins are present in plant cells.
Statement 2 is incorrect: Both plant and animal cells have a plasma membrane that surrounds the cytoplasm and regulates the movement of substances in and out of the cell. The plasma membrane is essential for maintaining homeostasis and facilitating communication between the cell and its environment in both plant and animal cells.
Statement 3 is correct: A mature plant cell typically contains a single, large central vacuole, which can occupy up to 90% of the cell’s volume. This vacuole stores water, nutrients, and waste products and helps maintain turgor pressure, providing structural support to the plant. Animal cells often have multiple small vacuoles scattered throughout the cytoplasm. These vacuoles perform similar storage and waste-management functions but are smaller and less prominent than those in plant cells. Animal Cell Plant Cell
UPSC 2020Science and Technology · Miscellaneous
Q22. In the context of recent advances in human reproductive technology. "Pronuclear Transfer" is used for
Explanation
Pronuclear transfer is an advanced reproductive technique primarily utilized to prevent the transmission of mitochondrial diseases from mother to offspring. Mitochondrial diseases are genetic disorders caused by mutations in mitochondrial DNA (mtDNA), which is inherited exclusively from the mother. These disorders can lead to severe health issues, affecting organs with high energy demands, such as the brain, heart, and muscles.
UPSC 2020Science and Technology · Miscellaneous
Q23. With reference to solar water pumps, consider the following statements: 1. Solar power can be used for running surface pumps and not for submersible pumps. 2. Solar power can be used for running centrifugal pumps and not the ones with piston. Which of the statements given above is/are correct?
Explanation
Statement 1 is incorrect: Solar power is capable of operating both surface and submersible pumps. Surface Pumps are installed above the water surface and are suitable for applications where water is drawn from shallow sources. They can be effectively powered by solar energy. Submersible pumps are designed to operate underwater. These pumps are ideal for deep wells or boreholes. Solar-powered submersible pumps are widely used for extracting water from significant depths.
Statement 2 is incorrect: Solar power can be utilized to run both centrifugal and piston (positive displacement) pumps. Centrifugal Pumps are commonly used in solar applications for higher flow rates with lower lift. They are efficient when adequate solar power is available. Piston Pumps also known as positive displacement pumps, piston pumps are suitable for applications requiring high lift with lower flow rates. Their ability to maintain efficiency under varying conditions makes them well-suited for solar-powered systems.
Exam tip:
Solar power is just a source of electricity. It can power any device that runs on electricity -- depending on how much power (wattage) you generate. Why would solar care about pump mechanism? It just supplies electricity. The motor and circuit handle the internal mechanics. Hence both statements are restrictive by saying "NOT"and hence likely false.
UPSC 2020Science and Technology · Miscellaneous
Q24. With reference to the current trends in the cultivation of sugarcane in India, consider the following statements: 1. A substantial saving in seed material is made when ‘bud chip settings’ are raised in a nursery and transplanted in the main field. 2. When direct planting of seeds is done, the germination percentage is better with single -budded setts as compared to setts with many buds. 3. If bad weather conditions prevail when seeds are directly planted, single - budded seeds have better survival as compared to large setts. 4. Sugarcane can be cultivated using settlings prepared from tissue culture. Which of the statements given above is/are correct?
Explanation
Tissue culture (TC) is the cultivation of plant cells, tissues, or organs on specially formulated nutrient media. Under the right conditions, an entire plant can be regenerated from a single cell. Commercial planting of sugarcane uses setts (cuttings that can form roots) at a rate of 6 to 8 tonnes per hectare, or around 10% of total production.
Statement 1 is correct: Due to its bulky attire and physical restrictions, the tissue culture method is becoming uneconomical. Planting excised axillary canestalk buds, sometimes referred to as budchips, would help reduce the mass and enhance the quality of the seed cane. After four to five weeks, healthy settlings are transplanted on a well-prepared field with a row spacing of 90 cm and a gap of 30 cm between each settling (small setts).
Statement 2 is incorrect: Due to moisture loss from the other cut end, the germination percentage of a single bud sett is extremely low. Numerous studies and trials demonstrate that the germination rate of 3 bud sets is higher than the setts having more or less than three buds. Additionally, even if the entire can stem is planted without being trimmed, only the top end will sprout, resulting in a poor germination percentage.
Statement 3 is incorrect: Under bad weather conditions, larger setts (multi-budded) generally have better survival rates compared to single-budded setts. This is because they store more nutrients and moisture, which helps them withstand adverse conditions better than single-budded setts.
Statement 4 is correct: The most crucial and labour-intensive step in sugarcane agriculture is planting. Supplying disease-free seed cane of current commercial types quickly is an innovative new technique, called tissue culture. It employs meristems to clone the mother plant. Tissue culture plants’ cane and sugar yields are comparable to those of plants grown using traditional methods.
Exam tip:
S2 and S3 seems counterintuitive. A sett with multiple buds has a higher chance that at least one will germi-nate. Single-budded setts are more vulnerable. Hence both are likely false. In bad weather, again, single buds are more fragile. Bigger setts might be physically more resilient and offer redundancy.
UPSC 2019Science and Technology · Miscellaneous
Q25. Atal Innovation Mission is set up under the:
Explanation
Atal Innovation Mission (AIM) by NITI Aayog is Government of India’s flagship initiative to promote a culture of innovation and entrepreneurship in the country and was setup in 2016. Towards this end AIM has taken a holistic approach to ensure creation of a problem-solving innovative mindset in schools and creating an ecosystem of entrepreneurship in universities, research institutions, private and MSME sector.
Additional insight:
AIM has launched the Atal Tinkering Lab (ATL) program. It is a state-of-the-art space established in a school with a goal to foster curiosity and innovation in young minds, between grade 6th to 12th across the country through 21st century tools and technologies. Atal Incubation Centres or AICs are business incubators established by AIM at universities, institutions and corporates to promote innovation and entrepreneurship among young innovators of the country. Atal Community Innovation Centres to promote the benefits of technology led innovation to the unserved/ underserved regions of India including Tier 2, Tier 3 cities, aspirational districts, tribal, hilly and coastal areas.
UPSC 2019Science and Technology · Miscellaneous
Q26. Consider the following statements: 1. According to the Indian Patents Act, a biological process to create a seed can be patented in India. 2. In India, there is no Intellectual Property Appellate Board. 3. Plant varieties are not eligible to be patented in India. Which of the statements given above is/are correct?
Explanation
Statement 1 is incorrect: The Indian Patents Act, 1970 (as amended in 2005) explicitly excludes biological processes for the production or propagation of plants and animals from patentability. The Act states that "plants and animals in whole or any part thereof, including seeds, varieties, and species, and essentially biological processes for the production or propagation of plants and animals" are not patentable.
Statement 2 is incorrect: India had an Intellectual Property Appellate Board (IPAB), which was established in 1958 to handle disputes related to patents, trademarks, and copyrights. However, IPAB was abolished in 2021 under the Tribunals Reforms (Rationalisation and Conditions of Service) Ordinance, 2021. After its abolition, patent, trademark, and copyright appeals are now handled by the High Courts.
Statement 3 is correct: Under the Indian Patents Act, 1970, plants and plant varieties cannot be patented. Instead, plant varieties are protected under the PPVFR Act, 2001, which grants breeders’ rights but not patents.
UPSC 2018Science and Technology · Miscellaneous
Q27. Consider the following statements: 1. The Earth’s magnetic field has reversed every few hundred thousand years. 2. When the Earth was created more than 4000 million years ago, there was 54% oxygen and no carbon dioxide. 3. When living organisms originated, they modified the early atmosphere of the Earth. Which of the statements given above is/are correct?
Explanation
Statement 1 is correct: The Earth’s magnetic field has undergone numerous reversals over geological time scales. These geomagnetic reversals occur at irregular intervals averaging approximately every 300,000 years though it varies.
Statement 2 is incorrect: Over 4000 million years ago earth’s early atmosphere lacked oxygen and was primarily composed of gases like methane, ammonia, water vapor, and carbon dioxide. The current level of oxygen (around 21%) accumulated much later due to photosynthetic activity by living organisms.
Statement 3 is correct: Living organisms particularly cyanobacteria played a significant role in modifying the Earth’s early atmosphere by producing oxygen through photosynthesis. This process led to the Great Oxygenation Event around 2.4 billion years ago. This marked a pivotal shift from an oxygen-poor to an oxygen-rich atmosphere, profoundly influencing the evolution of life.
UPSC 2018Science and Technology · Miscellaneous
Q28. ‘3D printing’ has applications in which of the following? 1. Preparation of confectionery items 2. Manufacture of bionic ears 3. Automotive industry 4. Reconstructive surgeries 5. Data processing technologies Select the correct answer using the code given below:
Explanation
3D printing, also known as additive manufacturing, is a method of creating a three dimensional object layer-by-layer using a computer simulated design. A 3D item is produced by the additive method of 3D printing, which involves building up layers of material. Options 1 is correct: 3D printing is widely used in the food industry to create intricate designs, especially with edible materials like chocolate and sugar. This technique enables customization and the production of unique shapes that are difficult to achieve with traditional methods. Options 2 is correct: Researchers have successfully used 3D printing to fabricate bionic ears by integrating biological cells with conductive materials. This method not only replicates the structure of a human ear but also enhances its functionality by embedding electronics, potentially improving hearing capabilities.
Option 3 is correct: In the automotive sector, 3D printing is used for rapid prototyping, creating tools, and manufacturing parts. It speeds up the design process, reduces production costs, and enables the creation of lightweight components, which improve vehicle performance and fuel efficiency.
Option 4 is correct: The healthcare sector leverages 3D printing for producing customized implants and prosthetics. In reconstructive surgeries, this technology allows for the creation of patient-specific implants that precisely match the patient’s anatomy, leading to better surgical outcomes.
Option 5 is correct: While 3D plays a significant role in data visualization. For instance, in scientific research, complex data sets can be transformed into tangible 3D models, enhancing the understanding of intricate structures.
Exam tip:
You can try, The "NOT" approach for all statements, this tests the improbability of negating a statement--if denying its impact seems highly unlikely, the statement is plausibly true.
UPSC 2017Science and Technology · Miscellaneous
Q29. Organic Light Emitting Diodes (OLEDs) are used to create digital displays in many devices. What are the advantages of OLED displays over Liquid Crystal displays? 1. OLED displays can be fabricated on flexible plastic substrates. 2. Roll-up displays embedded in clothing can be made using OLEDs. 3. Transparent displays are possible using OLEDs. Select the correct answer using the code given below:
Explanation
Statement 1 is correct: OLEDs can be manufactured on flexible materials such as polyethylene terephthalate (PET), which allows the creation of foldable and bendable screens. Unlike LCDs, which require rigid glass substrates, OLEDs can use lightweight and flexible plastics, enabling the development of innovative designs like foldable smartphones and rollable displays.
Statement 2 is correct: The flexibility and thinness of OLEDs make them suitable for rollable screens that can be integrated into textiles or wearable devices. This innovation enables the creation of electronic clothing or fabrics with embedded displays, providing new possibilities in wearable technology.
Statement 3 is correct: OLED technology supports the development of transparent displays because it does not rely on a backlight. OLEDs produce light on their own, making it possible to create see-through screens that overlay digital content on real-world environments.
UPSC 2016Science and Technology · Miscellaneous
Q30. India is an important member of the ‘International Thermonuclear Experimental Reactor’. If this experiment succeeds, what is the immediate advantage for India?
Explanation
The International Thermonuclear Experimental Reactor (ITER) is a collaborative international project involving countries such as India, China, the European Union, Japan, Korea, Russia, and the United States. Its primary goal is to demonstrate the feasibility of nuclear fusion as a sustainable and large-scale energy source by replicating the fusion processes that power the sun. If ITER succeeds then the immediate advantage for India would be the capability to construct fusion reactors for power generation. Fusion energy offers a carbon-free and environmentally sustainable alternative, with the potential to provide a significant amount of power compared to fossil fuels.
Answer key for these questions
Q
UPSC year
Correct answer
21
2020
(c) 1 and 3 only
22
2020
(d) prevention of mitochondrial diseases in offspring
23
2020
(d) Neither 1 nor 2
24
2020
(c) 1 and 4 only
25
2019
(c) NITI Aayog
26
2019
(c) 3 only
27
2018
(c) 1 and 3 only
28
2018
(d) 1, 2, 3, 4 and 5
29
2017
(c) 1, 2 and 3
30
2016
(d) It can build fusion reactors for power generation.
What UPSC has tested in Miscellaneous
Full battery electric vehicles, hydrogen fuel cell vehicles and fuel cell hybrids are all alternative powertrain vehicles.
The exhaust of a Fuel Cell Electric Vehicle is water vapour.
Cobalt, lithium and nickel form battery cathodes; graphite is used in the anode.
Pumped-storage hydropower is discussed as a long-duration energy storage option.
Rare earth elements are used in flat televisions and other electronics.
Frequently asked questions
How many previous year UPSC questions are there on Miscellaneous?
This page covers 68 previous year UPSC Prelims GS Paper-I questions on Miscellaneous (Science and Technology), asked from 2011 to 2025. Each has the correct answer and an explanation.
What does a hydrogen fuel cell vehicle emit?
Only water vapour. A fuel cell combines hydrogen with oxygen from the air to produce electricity, with water as the by-product, so the vehicle has no tailpipe carbon emissions.
Which elements form the cathode of an EV battery?
In lithium-ion batteries, the cathode contains lithium combined with cobalt, nickel, manganese or iron phosphate depending on chemistry. Graphite, by contrast, is used in the anode, not the cathode.
What is pumped-storage hydropower?
A way of storing energy by pumping water to a higher reservoir when electricity is cheap and releasing it through turbines when demand is high. It is used as long-duration storage that balances solar and wind power.
