Science & Technology

Pronuclear transfer, in the context of human reproductive technology, is used for preventing mitochondrial diseases in offspring.

Here's why - Mitochondria: These are cellular organelles with their own DNA (mitochondrial DNA or mtDNA) separate from nuclear DNA. Mutations in mtDNA can cause various inherited mitochondrial diseases that can affect organs like muscles, nerves, and the brain. - Pronuclear Transfer Technique: This technique involves the fertilization of an egg with sperm. Then, the pronuclei (nuclei before fusion) from both sperm and egg are removed. These pronuclei are then injected into a donor egg that has had its own pronuclei removed, but has healthy mtDNA.

Statement 1 is correct: Germline gene editing involves making genetic changes in the cells that produce eggs or sperms (germ cells). These changes are heritable and can be passed on to future generations. Techniques like CRISPR-Cas9 have made this scientifically possible.

Statement 2 is correct: Genome editing can be performed on early-stage embryos (zygotes or blastocysts) before they are implanted in the uterus. This allows for the correction of genetic mutations that cause hereditary diseases at the earliest stages of development.

Statement 3 is correct: Human induced pluripotent stem cells (hiPSCs) are adult cells reprogrammed to an embryonic-like state. Research has successfully demonstrated the injection of these human cells into pig embryos to create 'chimeras'. This technology is used to study organ development and explores the potential of growing human organs for transplantation in the future.

Therefore, all three statements are correct.

Statement 1 is correct. Blockchain technology operates as a decentralized and transparent ledger that records transactions across a network of computers. The ledger is publicly accessible, allowing anyone to inspect the transactions recorded on it. Additionally, no single user or entity has control over the entire blockchain network, as it is distributed among multiple nodes.

Statement 2 is incorrect. While blockchain technology is best known for its association with cryptocurrencies like Bitcoin, the blockchain itself is capable of recording various types of data beyond just financial transactions. Blockchain can be used to record and verify any type of digital information, such as contracts, identity documents, supply chain data, and more.

Statement 3 is correct. Blockchain technology enables the development of decentralized applications (DApps) that can operate without the need for central authority or permission. Developers can create applications that utilize the basic features of blockchain, such as transparency, immutability, and decentralization, without requiring approval from a central entity.

Statement 1 is correct. Pneumococcal Conjugate Vaccines (PCVs) are effective in preventing several serious diseases caused by Streptococcus pneumoniae bacteria. This includes pneumonia, meningitis (inflammation of the meninges surrounding the brain and spinal cord), and sepsis (a life-threatening blood infection).

Statement 2 is also correct. The growing prevalence of antibiotic-resistant strains of Streptococcus pneumoniae is a major concern. PCV vaccination helps reduce dependence on antibiotics, particularly for these resistant strains. This lowers the risk of antibiotic overuse and emergence of further resistance.

Statement 3 is incorrect. While most people experience no serious side effects with PCV vaccines, there can be mild reactions like redness, swelling, or soreness at the injection site. Serious allergic reactions are rare.

Statement 1 is correct. Visible Light Communication (VLC) utilizes the electromagnetic spectrum within the visible light range, which is roughly between 375 nm (violet) and 780 nm (red).

Statement 2 is incorrect. VLC is not considered long-range communication compared to other optical wireless technologies like fibre optics. Its range is typically limited to shorter distances due to factors like signal power and signal degradation.

Statement 3 is correct. VLC has the potential to transmit large amounts of data at high speeds, often faster than Bluetooth technology, especially in scenarios where high data transfer rates are required.

Statement 4 is also correct. VLC does not use radio frequencies (RF) like traditional wireless communication technologies, and therefore, it does not suffer from electromagnetic interference (EMI) that can affect RF-based systems.

Statement 1 is Correct: AI-driven automation and smart sensors optimize energy use in industrial units by predicting demand, monitoring equipment health, and adjusting operations in real-time to reduce waste.

Statement 2 is Incorrect: At the time of the 2020 UPSC examination, creating truly meaningful short stories and songs — possessing coherent narrative structure, genuine emotional depth, and creative intent — was considered beyond the effective reach of AI. The ability to produce such content meaningfully and autonomously, rather than through pattern recombination, had not been demonstrated at a level considered reliable or effective.

Statement 3 is Correct: AI is highly effective in medical diagnostics, particularly in analyzing medical imagery such as X-rays and MRIs to detect diseases like cancer, pneumonia, and diabetic retinopathy with high precision.

Statement 4 is Correct: Text-to-Speech conversion is a mature and well-established application of AI that utilizes natural language processing and neural networks to synthesize human-like speech from written text.

Statement 5 is Incorrect: Wireless transmission of electrical energy is a physical engineering process based on electromagnetic induction or microwaves. This is a function of physics and hardware, and not a task performed by Artificial Intelligence.

Statement 1 is Correct: Drones (Unmanned Aerial Vehicles) are widely used in precision agriculture for the targeted spraying of pesticides and liquid fertilizers, which helps in reducing chemical waste and minimizing human exposure to toxins. Statement 2 is Correct: Drones equipped with thermal cameras and gas sensors are used to inspect the craters of active volcanoes, allowing scientists to gather data from hazardous environments that are inaccessible or too dangerous for humans. Statement 3 is Correct: Researchers use specialized drones (such as the 'SnotBot') to fly through the blow (breath) of spouting whales to collect biological samples containing DNA, hormones, and microbiomes for non-invasive health monitoring.

The description mentions three spacecraft in an equilateral triangle formation with million-kilometre sides using lasers for measurement. This matches the design of the Evolved Laser Interferometer Space Antenna (eLISA) mission. eLISA is a proposed space observatory aiming to detect gravitational waves using precisely positioned spacecraft.

Voyager-2 and New Horizons are single spacecraft on exploration missions, not designed for gravitational wave detection.

LISA Pathfinder was a precursor mission to test technologies for eLISA, not the full mission itself.

Therefore, based on the details provided, the experiment refers to the Evolved LISA mission.

Atal Innovation Mission (AIM) is set up under the NITI Aayog (National Institution for Transforming India), which is the premier policy 'Think Tank' of the Government of India.

The Atal Innovation Mission was launched by the Government of India in 2016 to promote innovation and entrepreneurship across the country.

The key objectives of the Atal Innovation Mission are : 1. To create and promote an ecosystem of innovation and entrepreneurship across the country. 2. To establish Atal Tinkering Laboratories (ATLs) in schools across India to foster a culture of innovation from a young age. 3. To set up Atal Incubation Centres (AICs) to support entrepreneurs and startups. 4. To provide mentorship and funding support to innovative startups and entrepreneurs.

Statement 1 is correct. Wearable devices can perform several tasks, and out of given options, all three are achievable. Many smartwatches and wearables with GPS functionality can track a person's location. This can be helpful for navigation, fitness tracking, or safety purposes.

Statement 2 is correct. Wearable sleep trackers can monitor sleep patterns, including sleep duration, sleep stages (deep sleep, light sleep, REM sleep), and sleep quality.

Statement 3 is correct. Some wearables can function as hearing aids, amplifying sounds and improving hearing for people with hearing loss.

Therefore, the correct answer is 1, 2, and 3.

Statement 1 is incorrect. A digital signature doesn't directly identify the certifying authority that issued it. It uses a complex cryptographic process involving a public-key infrastructure (PKI) where a trusted third party (Certificate Authority) verifies the signer's identity and issues a digital certificate used for creating the signature.

Statement 2 is incorrect. While digital signatures can be used for authentication purposes in certain scenarios, they are not the primary method for user identification when accessing information or servers on the internet. Usernames, passwords, and other credentials are more commonly used.

Statement 3 is correct. It ensures the integrity of an electronic document by creating a unique digital fingerprint that is linked to the content. Any alteration to the document would invalidate the signature.

* The word 'Denisovan' is mentioned in the media about ancient humans (or an extinct human relative).

* Denisovans were a mysterious group of archaic humans who lived in Asia tens of thousands of years ago. They are most known for being discovered through genetic analysis of fossils, rather than complete skeletal remains.

Option A is the incorrect statement: While synthetic biology has enabled the creation of synthetic genomes (such as the synthetic bacterium *Mycoplasma mycoides*), creating a fully functional chromosome by joining DNA segments from different species is not currently feasible. Chromosomes are highly complex structures requiring specific regulatory elements and structural proteins that are often species-specific.

Option B is a correct statement: Synthetic biology and genetic engineering allow for the chemical synthesis of artificial DNA sequences with specific functions in a laboratory.

Option C is a correct statement: Polymerase Chain Reaction (PCR) is a standard laboratory technique used to replicate or amplify specific DNA segments outside of a living cell (in vitro).

Option D is a correct statement: Cell culture and tissue culture techniques allow cells extracted from plants and animals to be grown and undergo cell division in laboratory petri dishes using artificial nutrient media.

Remote sensing is the process of detecting and monitoring the physical characteristics of an area by measuring its reflected and emitted radiation at a distance from the targeted area.

Statement 1 is correct. Satellite images and remote sensing data can indeed be used to estimate the chlorophyll content in vegetation. This is done by measuring the reflectance of light from the vegetation. The chlorophyll in plants absorbs light for photosynthesis, and the amount of light reflected back can give an estimate of the chlorophyll content.

Statement 2 is correct. Satellite images and remote sensing data can also be used to estimate greenhouse gas emissions. This is done by detecting the radiations emitted by the substances in the rice paddies.

Statement 3 is correct. Satellite images and remote sensing data can be used to measure land surface temperatures as well. This is done by detecting the infrared radiation emitted by the land surface.

Therefore, all three parameters can be measured or estimated using satellite images or remote sensing data.

RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is a conserved biological response to double-stranded RNA that mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.

Statement 1 is correct. RNAi is a powerful tool for developing gene-silencing therapies. It allows researchers to target specific genes and reduce their expression, which can be beneficial in treating various diseases.

Statement 2 is also correct. RNAi is being actively explored for cancer therapy. By targeting genes involved in cancer cell growth and proliferation, RNAi has the potential to be a novel approach for cancer treatment.

Statement 3 is incorrect. RNAi is not typically used in developing hormone replacement therapies. Hormone replacement therapies introduce hormones into the body, while RNAi focuses on silencing gene expression within cells.

Statement 4 is correct. RNAi can be used to develop crop plants resistant to viral pathogens. By introducing specific RNA molecules that target the virus, plants can be made more resistant to viral infections, improving agricultural yields.

Statement 1 is incorrect. While genetic factors can contribute to susceptibility to infections, they are not directly related to the occurrence of multi-drug resistance in microbial pathogens.

Statement 2 is correct. Incorrect use of antibiotics, including taking incorrect doses or not completing the full course of treatment, can contribute to the development of drug resistance in microbial pathogens.

Statement 3 is correct. The widespread use of antibiotics in livestock farming can lead to the development of drug-resistant pathogens that can affect both animals and humans.

Statement 4 is incorrect. While individuals with chronic diseases may be more susceptible to infections, this factor is not directly related to the occurrence of multi-drug resistance in microbial pathogens.

* Cirrus clouds do not reflect a lot of solar radiation into space. As they form at high altitudes and cold temperatures, they trap long-wave radiation and have a climate impact similar to greenhouse gases. Thus, thinning cirrus clouds would reduce the absorption of infrared radiation and are proposed as a form of climate engineering to reduce global warming.


* Another proposed Geo-engineering technique involves injecting reflective sulphate aerosol particles into Earth's lower stratosphere to cast a small proportion of the inbound sunlight back into space and cool the planet off.

Thus, both are climate engineering/ Geo-engineering techniques to reduce global warming.

The merger of black holes is expected to generate powerful gravitational waves.

Gravitational waves are ripples in spacetime caused by accelerating massive objects. Detecting these waves with instruments like LIGO (Laser Interferometer Gravitational-Wave Observatory) allows us to study these events even when they are too far away or obscured to observe directly. This opens a new window for astronomical observations.

Statement 1 is incorrect: LTE is actually marketed as 4G, not 3G. VoLTE is not marketed as advanced 3G, but rather as an advancement over 4G LTE, allowing for voice calls over the 4G network.

Statement 2 is incorrect: LTE does primarily focus on providing high-speed data services, but it's not a data-only technology. VoLTE, on the other hand, is not a voice-only technology. It allows for voice calls to be made over the 4G LTE network, but it doesn't exclude data services.

Therefore, both statements are incorrect.

Statement 1 is incorrect. AR enhances the real world, not shuts it out. Augmented reality (AR) overlays digital elements on top of the real world, allowing users to see both simultaneously.

Statement 2 is incorrect. Virtual Reality (VR) creates a completely immersive and simulated environment that replaces the real world. Users wear a headset that blocks out their surroundings and projects a computer-generated world they can interact with.

Statement 3 is correct. AR often utilises the camera on a smartphone or PC to overlay digital elements onto the real world you see through the camera. This can enhance experiences in gaming, education, and even product visualisation.

Statement 4 is correct. VR creates a closed world, shutting out the physical environment and transporting the user entirely into a simulated one. This provides a highly immersive experience, often used for gaming, entertainment, and even training simulations.

Statement 1 is incorrect. According to the Indian Patents Act (specifically Section 3(j)), biological processes for the production or propagation of plants and animals are not eligible for patents. This means creating a seed through a biological process cannot be patented.

Statement 2 is incorrect. The Intellectual Property Appellate Board (IPAB) was established in India in 2003. It deals with appeals against decisions of the patent office and trademark registry.

Statement 3 is correct. Plant varieties themselves are not patentable in India. However, the Protection of Plant Varieties and Farmers' Rights Act (PPVFR Act) provides a system for protecting the rights of plant breeders by granting them exclusive rights to sell propagating material of new varieties.

_Note: the Tribunal Reforms Act, 2021 abolished various Tribunals including India's Intellectual Property Appellate Board (IPAB) and assigned their functions to the country's Commercial Courts and High Courts. However, UPSC asked this question in 2019 when an Appellate Board existed for intellectual property. Therefore correct answer is 3 only._

* Cas9 protein is a revolutionary tool in the field of genetic engineering.


* Cas9 is an RNA-guided endonuclease, an enzyme. It acts like molecular scissors, capable of cutting DNA at specific locations within a cell's genome.

* Cas9 plays a crucial role in the CRISPR-Cas9 (Clustered Regularly Interspaced Short Palindromic Repeats) technique, a powerful gene editing tool.

Option A is correct. Both Hepatitis B virus and HIV (Human Immunodeficiency Virus) can be transmitted through blood-to-blood contact, sexual contact, and from mother to child during childbirth.

Option B is incorrect. Unlike Hepatitis C, there is a vaccine available for Hepatitis B. The Hepatitis B vaccine is highly effective in preventing Hepatitis B virus infection.

Option C is correct. According to global health statistics, the number of people infected with Hepatitis B and C viruses combined is indeed several times more than those infected with HIV.

Option D is correct. Many individuals infected with Hepatitis B and C viruses may not show any symptoms for years or even decades. This is known as chronic hepatitis, and it can lead to severe liver damage if left untreated.


Dhara Mustard Hybrid-11, otherwise known as DMH - 11, is a genetically modified hybrid variety of the mustard species Brassica juncea.

Statement 1 is incorrect. The GM mustard developed in India does not have the property of pest-resistance. It has been genetically modified for hybridization and increased yield, not for pest-resistance.

Statement 2 is correct. The GM mustard has been developed with genes that allow it to cross-pollinate, leading to hybridization and increased yield.

Statement 3 is incorrect. The GM mustard was developed by scientists at Delhi University's Centre for Genetic Manipulation of Crop Plants (CGMCP), not by the IARI and Punjab Agricultural University.

So, only statement 2 is correct.


* THAAD is a missile defense system developed by the United States to intercept and destroy short, medium, and intermediate-range ballistic missiles during their terminal phase of flight.

* It is designed to defend against threats both within and outside the Earth's atmosphere, providing protection against potential missile attacks.

* THAAD has been deployed by the United States military and has also been sold to allied countries such as South Korea and Saudi Arabia.

Statement 1 is correct. PSLV (Polar Satellite Launch Vehicle) is primarily used to launch Earth observation/monitoring satellites, while GSLV (Geosynchronous Satellite Launch Vehicle) is designed to launch communication satellites into geosynchronous transfer orbits.

Statement 2 is incorrect. Satellites launched by PSLV are typically placed in polar or sun-synchronous orbits, which are not geosynchronous. These satellites appear to move across the sky as viewed from a particular location on Earth.

Statement 3 is incorrect. The GSLV Mk III is a three-stage launch vehicle, not a four-stage one. The first stage uses solid rocket motors, the second stage uses liquid rocket engines, and the third stage uses a cryogenic rocket engine.


GPS, or Global Positioning System, is a satellite-based navigation system that provides geolocation and time information to a GPS receiver anywhere on or near the Earth. It has a wide range of applications.

Statement 1 is correct. GPS is used in mobile phones for various purposes such as location tracking, navigation, and location-based services.

Statement 2 is correct. GPS is used in banking operations for ATM location services and for time-stamping transactions, which is crucial for maintaining accurate records.

Statement 3 is correct. GPS is used for time-stamping power system measurements, which is vital for grid stability and synchronization. Therefore, GPS technology can be used in all the three areas mentioned.

IRNSS is an independent regional navigation satellite system being developed by India.

Statement 1 is correct: The Indian Regional Navigation Satellite System (IRNSS) indeed has three satellites in geostationary orbits and four satellites in geosynchronous orbits.


Statement 2 is incorrect: It is designed to provide accurate position information service to users in India as well as the region extending up to 1500 km from its boundary, which is its primary service area. An Extended Service Area lies between primary service area and area enclosed by the rectangle from Latitude 30 deg South to 50 deg North, Longitude 30 deg East to 130 deg East.

Statement 3 is incorrect: While India has been working on enhancing the coverage of its navigation system, as of the given timeframe (2019), it does not have full global coverage. The system is primarily regional, although there are plans for augmentation and expansion.

The terms 'WannaCry, Petya and EternalBlue' are all related to cyber attacks.

* 'WannaCry' is a ransomware that locks users' devices and prevents them from accessing data and software until a certain ransom is paid to its creator.

* 'Petya' is another type of ransomware that spreads rapidly through networks that use Microsoft Windows.

* The Petya and WannaCry cyber-attacks in May and June 2017 are two of the biggest in history and impacted the finances of companies throughout the globe.

* 'EternalBlue' is a cyber exploit developed by the U.S. National Security Agency (NSA). It was used in the 2017 WannaCry ransomware attack and exploits a vulnerability in the Microsoft implementation of the Server Message Block (SMB) Protocol.

Pair 1 is incorrect: The Belle II experiment is a particle physics experiment designed to study the properties of B mesons. It is not related to artificial intelligence.

Pair 2 s correct: Blockchain technology is the underlying technology behind cryptocurrencies like Bitcoin. It is a distributed ledger technology that ensures secure and transparent transactions.


Pair 3 is incorrect: CRISPR-Cas9 is a gene-editing technology used in the field of molecular biology to edit genes. It is not related to particle physics.


Therefore, only pair 2 is correctly matched.