UPSC Prelims 2022 Analysis

Explanation

Statement 1 is correct. Probiotics can be made from both bacteria and yeast. Some common probiotic strains include bacteria like Lactobacillus and Bifidobacterium, and yeasts like Saccharomyces boulardii.

Statement 2 is incorrect. The organisms in probiotics are naturally found in the human gut. We have a complex gut microbiome with trillions of bacteria and other microbes, some of which are beneficial. Probiotics are supposed to introduce specific strains of these beneficial microbes to improve gut health.

Statement 3 is correct. Probiotics might help with lactose digestion, but it depends. Lactose intolerance is caused by a lack of the enzyme lactase, which breaks down lactose (milk sugar) in the gut. Some probiotic strains might produce lactase, potentially aiding digestion in lactose-intolerant individuals.

Explanation

Statement 1 is INCORRECT Covishield, produced by the Serum Institute of India, is a viral vector vaccine. It uses a weakened chimpanzee adenovirus vector to carry genetic material from the SARS-CoV-2 virus into human cells.

Statement 2 is CORRECT Sputnik V is a vector-based vaccine, similar to Covishield. It uses two different human adenovirus vectors to deliver genetic material coding for SARS-CoV-2 spike proteins.

Statement 3 is CORRECT COVAXIN, developed by Bharat Biotech, is an inactivated virus vaccine. This means the SARS-CoV-2 virus used in the vaccine is inactivated (killed) so it cannot cause infection, but it still triggers an immune response.

Explanation

Statement 1 is correct The Guchhi mushroom is a species of fungus in the Morchellaceae family of the Ascomycota. It exhibits a pale yellow colouration with large pits and ridges on the surface of the cap, which is elevated on a large white stem.

Statement 2 is correct This mushroom is cultivated in the foothills of the Himalayas, specifically in regions such as Himachal Pradesh, Uttaranchal, and Jammu and Kashmir.

Statement 3 is incorrect These mushrooms cannot be cultivated on a commercial scale and instead grow naturally in conifer forests across various temperature regions. It takes months for villagers to gather sufficient quantities of these mushrooms, dry them, and transport them to the market.

Explanation

Out of the listed effects of a major solar storm, the most likely ones are

A solar storm can disrupt the Earth's ionosphere, which can affect the signal transmission of GPS and other radio-based navigation systems.

Strong currents induced by the solar storm in power grids can damage transformers and cause widespread blackouts.

Solar storms can energize particles in the Earth's magnetosphere, leading to spectacular auroras at lower latitudes than usual.

The drag from a solar storm can alter the orbits of satellites, especially those in lower Earth orbit. . Similar to GPS, radio communication can be affected by disturbances in the ionosphere.

Tsunamis are caused by underwater earthquakes or volcanic eruptions, not solar storms. While a solar storm could potentially ignite some fires through electrical sparks, this is not a widespread effect.

Therefore, codes 2 and 5 should not form the part of answer.

Explanation

• Ants are well-known as cultivators of fungi. Certain ant species, particularly those in the tribe Attini, have evolved a symbiotic relationship with specific fungi. These ants cultivate the fungus within their nests, providing it with food and a controlled environment. In return, the fungus provides the ants with nutrients. This is a fascinating example of mutualism in nature.

• Cockroaches are omnivores and scavengers. They do not cultivate fungi.

• Crabs are primarily scavengers or predators. They are not known to cultivate fungi.

• Spiders are predators and capture their prey (insects) in webs. They do not cultivate fungi.

Explanation

Statement 1 is incorrect. Nanoparticles can exist in nature (natural nanoparticles). Volcanic eruptions, forest fires, and natural weathering processes can all create nanoparticles.

Statement 2 is correct. Some cosmetics incorporate nanoparticles of ingredients like zinc oxide or titanium dioxide for sun protection or other purposes.

Statement 3 is also correct The safety of nanoparticles in consumer products is a complex issue and a growing area of research. Some nanoparticles might pose potential health or environmental risks depending on their specific properties and how they interact with the body or the environment.

Explanation

Out of the listed communication technologies, all three can be considered short-range devices/technologies.

Closed-Circuit Television (CCTV): CCTV systems primarily use cables or wireless connections with a limited range, typically within a building or a designated area.

Radio Frequency Identification (RFID): RFID uses radio waves to identify objects. The reading range of RFID tags depends on the specific technology but generally falls within the short-range category, from a few centimetres to a few meters.

Wireless Local Area Network (WLAN): WLANs, commonly known as Wi-Fi networks, typically operate within a range of tens of meters indoors and up to hundreds of meters outdoors depending on factors like signal strength and frequency band. While the range might be slightly larger than the others on this list, WLANs still fall under the short-range classification compared to technologies like cellular networks or satellite communication.

Explanation

B cells and T cells are both key components of the human immune system, which defend the body against harmful invaders like viruses, bacteria, and parasites.

B cells produce antibodies that can specifically target and neutralize pathogens.

T cells help orchestrate the immune response by directly attacking infected cells or by stimulating other immune cells.

Explanation

Statement 1 is incorrect. DNA Barcoding cannot assess the age DNA barcoding primarily focuses on identifying species based on their unique genetic sequences.

Statement 2 is correct. DNA barcoding is a valuable tool for distinguishing between species that appear similar morphologically. By analyzing short, standardized DNA sequences, scientists can efficiently and accurately identify different species, even if they look very alike.

Statement 3 is correct. DNA barcoding can be used to identify the origin and composition of food products. This can help detect cases where cheaper or undesirable ingredients (food adulteration) are substituted for the ones listed on the label. For example, it can be used to identify different types of meat in processed foods.

Therefore, statements 2 and 3 are correct.

Explanation

It is a delivery system that uses a low Earth orbit to bypass early warning systems and deliver warheads on targets very quickly.

FOBS launches a warhead into a low Earth orbit trajectory instead of a full ballistic missile arc.

These systems are typically designed to detect missiles launched on high ballistic trajectories. A FOBS warhead in a low orbit might be harder to detect until it re-enters the atmosphere for its final approach to the target.

Due to the orbital path, the time between re-entry and target impact can be shorter compared to a traditional ballistic missile attack.

Explanation

Statement 1 is correct. NFTs can be associated with digital assets like artwork, music, or videos. They act as a certificate of ownership for these digital items.

Statement 2 is correct NFTs are unique cryptographic tokens stored on a blockchain, a secure digital ledger. This ensures transparency and traceability of ownership.

Statement 3 is incorrect. NFTs are not fungible, meaning they are not interchangeable like currencies. Each NFT has unique properties and value, unlike a dollar bill where one can be replaced by another. While NFTs can be traded, their value depends on individual characteristics and market demand, making them unsuitable for everyday transactions like buying groceries.

Explanation

In many cases, Software as a Service (SaaS) providers allow some degree of customization of the user interface and data fields to meet the specific needs of their customers.

One of the key benefits of SaaS is its accessibility from anywhere with an internet connection, including mobile devices such as smartphones and tablets. SaaS applications are often designed to be mobile-friendly, allowing users to access their data and perform tasks on the go.

Outlook, Hotmail, and Yahoo! Mail are examples of web-based email services that operate on the SaaS model. Users access these email services through web browsers without needing to install or maintain any software locally on their devices. The email data is stored and managed remotely on servers operated by the service providers.

Therefore, all statements are correct.

Explanation

A key aspect of Web 3.0 is the concept of decentralization, where users have more control and ownership over their personal data, rather than having it stored and controlled by centralized platforms.

Blockchain technology is a core component of Web 3.0, and it can enable the creation of decentralized, user-owned social networks and platforms.

The decentralized nature of Web 3.0 means that it is not controlled by a single corporation or entity, but rather operated and maintained collectively by the users and participants in the network.

Therefore, all three statements regarding Web 3.0 are correct.

Explanation

Biofilms are a major concern in healthcare. They can form on implanted devices like catheters, heart valves, and artificial joints within human tissues. These biofilms can harbour bacteria that are difficult to eradicate with antibiotics, leading to chronic infections and potential implant failure.

Biofilms can also form on food and food processing surfaces. This can contaminate food with bacteria and contribute to spoilage. Biofilms on these surfaces are also challenging to remove due to their protective matrix.

Bacteria within biofilms can exhibit increased resistance to antibiotics. The biofilm matrix acts as a barrier, making it harder for antibiotics to reach and kill the bacteria. Additionally, bacteria within biofilms can communicate and share genetic material, potentially promoting the spread of antibiotic resistance genes.

All three statements are correct.

Explanation

• A qubit is the fundamental unit of information in quantum computing, analogous to the bit in classical computing.

• However, unlike a bit that can only be either 0 or 1, a qubit can exist in a superposition of both states simultaneously.

• This property of qubits allows quantum computers to perform certain calculations much faster than traditional computers.