UPSC IAS PRELIMS 2019 GS PAPER I DETAILED EXPLANATIONS PART -V, Q 41 TO Q 50

Q 41. In the context of digital technologies for entertainment, consider the following statements:

1. In Augmented Reality (AR) , a simulated environment is created and the physical world is completely shut out.

2. In Virtual Reality (VR), images generated from a computer are projected onto real-life objects or surroundings.

3. AR allows individuals to be present in the world and improves the experience using the camera of smart-phone or PC.

4. VR closes the world, and transposes an individual, providing complete immersion experience.

Which of the statements given above is / are correct?

(a) 1 and 2 only

(b) 3 and 4

(c) 1, 2 and 3

(d) 4 only

Answer: b

EXPLANATION

Augmented reality (AR) adds digital elements to a live view often by using the camera on a smartphone. Examples of augmented reality experiences include Snapchat lenses and the game Pokemon Go.

Virtual reality (VR) implies a complete immersion experience that shuts out the physical world. Using VR devices such as HTC Vive, Oculus Rift or Google Cardboard, users can be transported into a number of real-world and imagined environments such as the middle of a squawking penguin colony or even the back of a dragon.

In a mixed reality (MR) experience, which combines elements of both AR and VR, real-world and digital objects interact. Mixed reality technology is just now starting to take off with Microsoft’s HoloLens one of the most notable early mixed reality apparatuses.

Q 42. The word ‘Denisovan’ is sometimes mentioned in media in reference to

(a) fossils of a kind of dinosaurs

(b) an early human species

(c) a cave system found in North-East India.

(d) a geological period in the history of Indian subcontinent

Answer: b

EXPLANATION

The Denisovans or Denisova hominins are an extinct species or subspecies of archaic humans in the genus Homo. Pending its taxonomic status, it currently carries temporary species or subspecies names Homo denisova, Homo altaiensis, Homo sapiens denisova, or Homo sp. Altai.

In 2010, scientists announced the discovery of an undated finger bone fragment of a juvenile female found in the Denisova Cave in the Altai Mountains in Siberia, a cave that has also been inhabited by Neanderthals and modern humans. The mitochondrial DNA (mtDNA) of the finger bone showed it to be genetically distinct from Neanderthals and modern humans.

The nuclear genome from this specimen suggested that Denisovans shared a common origin with Neanderthals, that they ranged from Siberia to Southeast Asia, and that they lived among and interbred with the ancestors of some modern humans, with about three to five percent of the DNA of Melanesians and Aboriginal Australians and around six percent in Papuans deriving from Denisovans.

Q 43. With reference to the recent developments in science, which one of the following statements is not correct?

(a) Functional chromosomes can be created by joining segments of DNA taken from cells of different species.

(b) Pieces of artificial functional DNA can be created in Iaboratories.

(c) A piece of DNA taken out from an animal cell can be made to replicate outside a living cell in a laboratory.

(d) Cells taken out from plants and animals can be made to undergo cell division in laboratory petri dishes.

Answer: a

Q 44. Consider the following statements:

A digital signature is

1. an electronic record that identifies the certifying authority issuing it

2. used to serve as a proof of identity of an individual to access information or server on Internet.

3. an electronic method of signing an electronic document and ensuring that the original content is unchanged

Which of the statements given above is / are correct?

(a) 1 only

(b) 2 and 3 only

(c) 3 only

(d) 1, 2 and 3

Answer: d

EXPLANATION

A digital signature is basically a way to ensure that an electronic document (e-mail, spreadsheet, text file, etc.) is authentic. Authentic means that you know who created the document and you know that it has not been altered in any way since that person created it.

Digital signatures rely on certain types of encryption to ensure authentication. Encryption is the process of taking all the data that one computer is sending to another and encoding it into a form that only the other computer will be able to decode. Authentication is the process of verifying that information is coming from a trusted source. These two processes work hand in hand for digital signatures.

Q 45. In the context of wearable technology, which of the following tasks is/are accomplished by wearable devices?

1. Location identification of a person

2. Sleep monitoring of a person

3. Assisting the hearing impaired person

Select the correct answer using the code given below.

(a) 1 only

(b) 2 and 3 only

(c) 3 only

(d) 1, 2 and 3

Answer: d

Wearable technology, wearables, fashion technology, tech togs, or fashion electronics are smart electronic devices (electronic device with micro-controllers) that can be incorporated into clothing or worn on the body as implants or accessories.

Wearable devices such as activity trackers are an example of the Internet of Things, since “things” such as electronics, software, sensors, and connectivity are effectors that enable objects to exchange data (including data quality) through the internet with a manufacturer, operator, and/or other connected devices, without requiring human intervention.

Wearable technology has a variety of applications which grows as the field itself expands. It appears prominently in consumer electronics with the popularization of the smartwatch and activity tracker. Apart from commercial uses, wearable technology is being incorporated into navigation systems, advanced textiles, and healthcare.

Q 46. ‘RNA interference (RNAi)’ technology has gained popularity in the last few years. Why?

1. It is used in developing gene silencing therapies.

2. It can be used in developing therapies for-the treatment of cancer.

3. It can be used to develop hormone replacement therapies.

4. It can be used to produce crop plants that are resistant to viral pathogens.

Select the correct answer using the code given below.

(a) 1, 2 and 4

(b) 2 and 3

(c) 1 and 3

(d) 1 and 4 only

Answer: a

EXPLANATION

RNA interference (RNAi) is a biological process in which RNA molecules inhibit gene expression or translation, by neutralizing targeted mRNA molecules. Historically, RNAi was known by other names, including co-suppression, post-transcriptional gene silencing (PTGS), and quelling. The detailed study of each of these seemingly different processes elucidated that the identity of these phenomena were all actually RNAi.

Andrew Fire and Craig C. Mello shared the 2006 Nobel Prize in Physiology or Medicine for their work on RNA interference . Since the discovery of RNAi and its regulatory potentials, it has become evident that RNAi has immense potential in suppression of desired genes.

RNAi is now known as precise, efficient, stable and better than antisense technology for gene suppression.

Q 47. Recently, scientists observed the merger of giant ‘blackholes’ billions of light-years away from the Earth. What is the significance of this observation?

(a) ‘Higgs boson particles’ were detected.

(b) ‘Gravitational waves’ were detected.

(e) Possibility of inter-galactic space travel through ‘wormhole’ was confirmed.

(d) It enabled the scientists to understand ‘singularity’.

Answer: b

EXPLANATION

Gravitational waves are ‘ripples’ in space-time caused by some of the most violent and energetic processes in the Universe. Albert Einstein predicted the existence of gravitational waves in 1916 in his general theory of relativity.

Einstein’s mathematics showed that massive accelerating objects (such as neutron stars or black holes orbiting each other) would disrupt space-time in such a way that ‘waves’ of distorted space would radiate from the source (like the movement of waves away from a stone thrown into a pond).

Furthermore, these ripples would travel at the speed of light through the Universe, carrying with them information about their cataclysmic origins, as well as clues to the nature of gravity itself.

The strongest gravitational waves are produced by catastrophic events such as colliding black holes, the collapse of stellar cores (supernovae), coalescing neutron stars or white dwarf stars, the slightly wobbly rotation of neutron stars that are not perfect spheres, and possibly even the remnants of gravitational radiation created by the birth of the Universe.

Q 48. Which of the following are the reasons for the occurrence of multi-drug resistance in microbial pathogens in India?

1. Genetic predisposition of some people

2. Taking incorrect doses of antibiotics to cure diseases

3. Using antibiotics in livestock farming

4. Multiple chronic diseases in some people

Select the correct answer using the code given below.

(a) 1 and 2

(b) 2 and 3 only

(e) 1, 3 and 4

(d) 2, 3 and 4

Answer: b

EXPLANATION

Antimicrobial resistance (AMR or AR) is the ability of a microbe to resist the effects of medication that once could successfully treat the microbe.

Microbes resistant to multiple antimicrobials are called multidrug resistant (MDR). Those considered extensively drug resistant (XDR) or totally drug-resistant (TDR) are sometimes called “superbugs”.

Resistance arises through one of three mechanisms: natural resistance in certain types of bacteria, genetic mutation, or by one species acquiring resistance from another. All classes of microbes can develop resistance. Fungi develop antifungal resistance. Viruses develop antiviral resistance. Protozoa develop antiprotozoal resistance, and bacteria develop antibiotic resistance.

Rising drug resistance is caused mainly by use of antimicrobials in humans and other animals, and spread of resistant strains between the two. Growing resistance has also been linked to dumping of inadequately treated effluents from the pharmaceutical industry, especially in countries where bulk drugs are manufactured.

Q 49. What is Cas9 protein that is often mentioned in news?

(a) A molecular scissors used in targeted gene editing

(b) A biosensor used in the accurate detection of pathogens in patients

(c) A gene that makes plants pest-resistant

(d) A herbicidal substance synthesized in genetically modified crops

Answer: a

EXPLANATION

Cas9 (CRISPR associated protein 9) is a protein which plays a vital role in the immunological defense of certain bacteria against DNA viruses, and which is heavily utilized in genetic engineering applications. Its main function is to cut DNA and therefore it can alter a cell’s genome.

More technically, Cas9 is an RNA-guided DNA endonuclease enzyme associated with the CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) adaptive immunity system in Streptococcus pyogenes, among other bacteria.

Q 50. Which one of the following statements is not correct?

(a) Hepatitis B virus is transmitted much like HIV.

(b) Hepatitis B, unlike Hepatitis C, does not have a vaccine.

(c) Globally, the number of people infected with Hepatitis B and C viruses are several times more than those infected with HIV.

(d) Some of those infected with Hepatitis B and C viruses do not show the symptoms for many years.

Answer: b

EXPLANATION

How is hepatitis B spread?
The hepatitis B virus is spread when blood, semen, or other body fluid infected with the hepatitis B virus enters the body of a person who is not infected. People can become infected with the virus from:

1.Birth (spread from an infected mother to her baby during birth)
2.Sex with an infected partner
3.Sharing needles, syringes, or drug preparation equipment
4.Sharing items such as toothbrushes, razors or medical equipment such as a glucose monitor with an infected person
5.Direct contact with the blood or open sores of an infected person
6.Exposure to blood from needlesticks or other sharp instruments of an infected person

Hepatitis B virus is not spread through food or water, sharing eating utensils, breastfeeding, hugging, kissing, hand holding, coughing, or sneezing.

The best way to prevent hepatitis B is by getting vaccinated.

There are vaccines to prevent hepatitis A and hepatitis B; however, there is no vaccine for hepatitis C