Union Public Service Commission(UPSC) Previous Year 2019 Questions and Answers

1 .

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.

Correct Answer : Hepatitis B, unlike Hepatitis C, does not have a vaccine.

Note : A hepatitis B vaccine protects against hepatitis B virus (HBV) infection, a contagious disease that damages the liver. The vaccine is given as a shot. Examples of hepatitis B vaccines approved by the U.S. Food and Drug Administration (FDA) to prevent HBV infection include Engerix-B and Recombivax HB (both brand names). It proves that Hepatitis B does have a vaccine and hence, option (b) is not correct.

Year : 2019

Category : Science and Technology

2 .

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 pestresistant

D)

A herbicidal substance synthesized in genetically modified crops

Correct Answer : A molecular scissors used in targeted gene editing

Note : The key step in editing an organism‘s genome is selective targeting of a specific sequence of DNA. Two biological macromolecules, the Cas9 protein and guide RNA, interact to form a complex that can identify target sequences with high selectivity. The Cas9 protein is responsible for locating and cleaving target DNA, both in natural and in artificial CRISPR/Cas9 systems.

Year : 2019

Category : Science and Technology

3 .

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

C)

1, 3 and 4

D)

2, 3 and 4

Correct Answer : Option (B) - 2 and 3 only

Note : Scientists also believe that the practice of adding antibiotics to agricultural feed promotes drug resistance. More than half of the antibiotics produced in the United States are used for agricultural purposes. 1, 2 However, there is still much debate about whether drug-resistant microbes in animals pose a significant public health burden.

Source : NIAID

Year : 2019

Category : Science and Technology

4 .

Recently, scientists observed the merger of giant 'blackholes' billions of lightyears away from the Earth. What is the significance of this observation?

A)

'Higgs boson particles' were detected.

B)

'Gravitational waves' were detected.

C)

Possibility of inter-galactic space travel through 'wormhole' was confirmed.

D)

It enabled the scientists to understand 'singularity'.

Correct Answer : 'Gravitational waves' were detected.

Note :

In the experiment it was observed that the two black holes that merged were massive : one hole was 31 times the mass of the sun, and the other was 25 solar masses. They twisted together to form a single spinning hole 53 times more massive than our star. The missing three suns' worth of mass became energy, expelled as gravitational waves.

In the experiment it was observed that gravitational wave detectors, detected signals from events involving objects other than black holes. Whereas black holes emit no electromagnetic radiation and are impossible to directly observe, other potential sources of gravitational waves — colliding neutron stars, supernovas, binary star mergers — can be seen through conventional telescopes. Hence the second statement is correct.

Year : 2019

Category : Science and Technology

5 .

'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

Correct Answer : Option (A) - 1, 2 and 4

Year : 2019

Category : Science and Technology

6 .

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

Correct Answer : Option (D) - 1, 2 and 3

Note : Wearable technology works in the health care space eg fitness and sleep trackers like embrace help record heart rate and sleep pattern. It can be connected through GPS and can identify locations. It also assists the hearing-impaired persons. Hence all the statements are correct.

Year : 2019

Category : Science and Technology

7 .

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

Correct Answer : Option (D) - 1, 2 and 3

Note :

* Digital signatures offer many advantages. Not only you know that a certain person has signed a specific document (statement 1 is correct) but that was also the exact information he signed.

* Once a digital signature has been placed the document cannot be altered anymore (statement 3 is correct), or it will lead to an invalid digital signature.

* Next to that digital signatures can be used for many purposes such as contracts, payment instructions, confirmations but of course also to maintain the integrity of the data. A digital signature is based on public key cryptography, which means that every user has a secret and a public key.

* The secret key is used to place a digital signature on e.g. a document and with the public key the signature can be verified. To maintain the integrity of the public key it will be made available in the form of a certificate. There are several levels of trust possible for certificates, ranging from self-signed to qualified certificates. Important for digital signatures is proof of identity of the holder of the certificate, and eliminating risks in the process as much as possible. (Statement 2 is correct)

Year : 2019

Category : Science and Technology

8 .

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 laboratories.

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.

Correct Answer :

Note : In our opinion the question is wrong.

Statement 1 is how we define recombinant DNA technology,
Statement 2 is also right and the process is called as polynucleotide synthesis.
Statement 3 is referring to polymerase chain reaction and statement 4 is all about tissue culture.

Year : 2019

Category : Science and Technology

9 .

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

Correct Answer : an early human species

Note : Scientists sifting through the genomes of people scattered across the islands of south-east Asia have found echoes of ancient pairings with not just one, but three separate populations of the archaic hominins known as Denisovans. First discovered in 2010, the Denisovans are a relatively recent addition to the human family tree.

Year : 2019

Category : Science and Technology

10 .

In the context of digital technologies for entertainment consider the following statements:

1. ln 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

Correct Answer : Option (B) - 3 and 4

Note :

Virtual reality (VR) is an artificial, computer-generated simulation or recreation of a real life environment or situation. It immerses the user by making them feel like they are experiencing the simulated reality first-hand, primarily by stimulating their vision and hearing. Hence statement 2 is not correct but 4 is correct.

Augmented reality (AR) is a technology that layers computer-generated enhancements atop an existing reality in order to make it more meaningful through the ability to interact with it. AR is developed into appsand used on mobile devices to blend digital components into the real world in such a way that they enhance one another, but can also be told apart easily. Hence statement 1 is not correct but 3 is correct.

Year : 2019

Category : Science and Technology

UPSC 2019 (Prelims & Mains) Questions