UPSC Prelims Previous Year Questions 2019: Science & Technology

Ans: (c)
AlM's objectives are to create and promote an ecosystem of innovation and entrepreneurship across the country at school, university, research institutions, MSME and industry levels. The Mission has been set up under NITI Aayog, in accordance with the Hon'ble Finance Minister's declaration in the 2015 Budget Speech.

Ans: (d)

• Statement 1: The Sentinel satellite of the European Space Agency has certain specific spectral characteristics that can be used to measure even the chlorophyll content in the vegetation of a specific location. Correct.
• Statement 2: Estimation of Methane Emissions from Rice Paddies in the Mekong Delta Based on Land Surface Dynamics Characterization with Remote Sensing. Correct.
• Statement 3: The land surface temperature of a specific location can be measured with the help of satellite images/ remote sensing data. Correct.

Ans: (d)

• Exp: LTE improved on the radio technology of 3G's WCDMA and introduced OFDM or Orthogonal Frequency-Division Multiplexing. ITU (The International Telecommunication Union) recognises the lack of clarity in the term 4G and has determined LTE-Advanced and WirelessMAN-Advanced or WiMax 2 as "True" 4G.
• VoLTE is a technology update to the LTE protocol used by mobile phone networks. Under LTE, the infrastructure of telecom players only allows transmission of data while voice calls are routed to their older 2G or 3G networks.
• Basically VoLTE systems covert voice into data stream, which is then transmitted using the data connection.

Ans: (b)
Virtual reality (VR) immerses users in a fully artificial digital environment. Augmented reality (AR) overlays virtual objects on the real-world environment. Mixed reality (MR) not just overlays but anchors virtual objects to the real world.

Ans: (a)
In a major step toward creating artificial life, US researchers have developed a living organism that incorporates both natural and artificial DNA and is capable of creating entirely new, synthetic proteins. Hence, option (b) is correct. A wide variety of double-stranded DNA templates are replicated extensively in an in vitro DNA replication system containing the purified proteins specified by seven T4 bacteriophage DNA replication genes (32, 41, 43, 44, 62, 45, and 61). Hence, option (c) is correct. Through micropropagation plant can be developed in laboratory and chlamydomnas cells can be replicated in culture through light variations. Hence, option (d) is correct.

Ans: (c)
If we consider Digital Signature same as Digital Signature Certificate then option should be d). The certificate contains information about the user's identity (name, pin code, country, email address, the date the certificate was issued and the name of the certifying authority). However, if they are considered as different, then the answer should be c).

Ans: (d)
In recent times, there has been a new surge in wearable technology worn on the ear, referred to as hearables. Wearable technology is a category of electronic devices that can be worn as accessories, embedded in clothing, implanted in the user's body, or even tattooed on the skin.

Ans: (a)
RNA interference (RNAi), regulatory system occurring within eukaryotic cells (cells with a clearly defined nucleus) that controls the activity of genes. RNAi functions specifically to silence, or deactivate, genes. RNAi is being explored as a form of treatment for a variety of diseases, including macular degeneration, hepatitis, AIDS, Huntington disease, and cancer. RNAi is used as a natural defense mechanism against molecular parasites such as jumping genes and viral genetic elements.

Ans: (b)
When the two supermassive black holes in each of these systems finally come together in millions of years, their encounters will produce strong gravitational waves. Gravitational waves produced by the collision of two stellar-mass black holes have already been detected by the Laser Interferometer Gravitational-Wave Observatory (LIGO). Observatories such as the planned NASA/ESA space-based Laser Interferometer Space Antenna (LISA) will be able to detect the lower-frequency gravitational waves from supermassive black-hole mergers, which are a million times more massive than those detected by LIGO.

Ans: (d)
Antimicrobial resistance occurs naturally over time, usually through genetic changes. However, the misuse and overuse of antimicrobials is accelerating this process. In many places, antibiotics are overused and misused in people and animals, and often given without professional oversight. Examples of misuse include when they are taken by people with viral infections like colds and flu, and when they are given as growth promoters in animals or used to prevent diseases in healthy animals.

Ans: (a)
CRISPR Cas9 is an acronym for "Clustered Regularly Interspaced Short Palindromic Repeats." CRISPR genome engineering technology enables scientists to easily and precisely edit the DNA of any genome.

Ans: (b)
The hepatitis B vaccine is a safe and effective vaccine that is recommended for all infants at birth and for children up to 18 years. The hepatitis B vaccine is also known as the first "anti-cancer" vaccine because it prevents hepatitis B, the leading cause of liver cancer worldwide.