UPSC 2021 Prelims Questions with Answers

Explanation

Permaculture is a totally integrated design system that’s modelled on nature.

Statement 1 is correct: Permaculture farming promotes multi-cropping and integrated farming systems. While chemical farming is more suitable for monoculture cropping due to the use of crop-specific inputs like irrigation, chemical fertiliser and harvesting methods.

Statement 2 is correct: Conventional farming usually alters the natural environment, increases soil salinity, and eliminates biodiversity. Such problems are not seen in permaculture farming as it relies on organic fertilizers.

Statement 3 is incorrect: Chemical farming is based on the intense use of inputs like chemical fertilizers and irrigation that make the soil less fertile over time, thus restricting its practice in semi-arid regions. Thus, conventional farming is not suitable for semi-arid regions. Permaculture involves well-designed systems that don’t produce waste and permaculture tries to imitate well-designed systems. Thus, it can work in arid climates as well.

Statement 4 is correct: Mulching is an important component of Permaculture systems for promoting maximum efficiency.

Explanation

Climate-Smart Agriculture (CSA) is a strategy to assist those in charge of managing agricultural systems in efficiently adapting to climate change. The CSA approach pursues the triple objectives of:

Sustainably increasing productivity and incomes Adapting to climate change Reducing greenhouse gas emissions where possible

Statement 1 is correct: The Climate-Smart Village project in India is a CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS).

Statement 2 is correct: Climate Change, Agriculture and Food Security (CCFAS) is carried out under CGIAR (formerly the Consultative Group for International Agricultural Research).

Statement 3 is correct: ICRISAT is a CGIAR Research Center. It is a non-profit, non-political public international research organization that conducts agricultural research for development in Asia and sub-Saharan Africa with a wide array of partners throughout the world.

Explanation

Adenoviruses are non-enveloped, double-stranded DNA viruses that infect a wide range of hosts, including humans. They are known for their ability to efficiently infect various cell types. A retrovirus is a virus that uses RNA as its genetic material. Upon infection with a retrovirus, a cell converts the retroviral RNA into DNA, which in turn is inserted into the DNA of the host.

Statement 1 is incorrect: Adenoviruses possess linear, double-stranded DNA genomes whereas retroviruses have single-stranded RNA genomes. Upon infecting a host cell, retroviruses use the enzyme reverse transcriptase to convert their RNA into double-stranded DNA, which is then integrated into the host’s genome.

Statement 2 is correct: Adenoviruses are known to cause respiratory illnesses, including symptoms similar to the common cold. AIDS (Acquired Immunodeficiency Syndrome) is caused by the Human Immunodeficiency Virus (HIV), which is a retrovirus.

Explanation

A Recombinant Vector Vaccine is a vaccine that uses a genetically modified virus or bacterium as a carrier to deliver pathogen-specific genes, triggering an immune response.

Statement 1 is correct: Recombinant vector vaccines are developed using genetic engineering to insert genes encoding antigens into harmless viruses or bacteria, which serve as vectors. These vectors deliver the genetic material into the body, enabling the expression of target antigens and triggering an immune response against the pathogen. Examples include viral vector vaccines like Oxford-AstraZeneca (ChAdOx1 nCoV-19) and Sputnik V for COVID-19.

Statement 2 is correct: Both bacteria (such as Salmonella) and viruses (such as adenoviruses and vesicular stomatitis virus) can be used as vectors to deliver genetic material into host cells to stimulate an immune response.

Explanation

Ancient and medieval Indian playwrights and dramatists, like Bhasa, Kalidasa, and Bhavabhuti, created masterpieces that blended poetry, philosophy, and performance. Bhavabhti was an 8th-century scholar of India noted for his plays and poetry, written in Sanskrit. He is known as "Poet of Karun Rasa" for his work named as Uttararamacharita. His written plays include Mahavircharitra and Malatimadhava. Hastimalla was a Kannada poet and playwright during Hoysalas’ reign. He wrote 8 plays including ’VikrantKaurava’ and ’Subhadra Harana’ Kshemeshvara was an 11th-century Sanskrit poet from Kashmir in India. One of the important works attributed to him is the Dasavatar Charita.

Explanation

Statement 1 is incorrect: The distinction between Mitakshara and Dayabhaga is not based on caste i.e. upper or lower castes but on regional variations of Hindu law. Mitakshara was prevalent in most parts of India, whereas Dayabhaga was primarily followed in Bengal and parts of Assam.

Statement 2 is correct: Both were Hindu law books and governed property rights and inheritance. The Mitakshara was written by Vijnanesvara, a scholar in the Kalyani Chalukya court in the late 11th century. The Dayabhaga was authored by Jimutavahana, a 12th-century scholar from Bengal. In the Mitakshara system, sons acquire a right to ancestral property by birth, meaning they have a share in the joint family property during the father’s lifetime. In the Dayabhaga system, sons do not have a right to the property until the father’s death.

Statement 3 is incorrect: The Mitakshara system historically favored male descendants, with females becoming coparceners only after the Hindu Succession Act, 2005. In contrast, the Dayabhaga system provides relatively better property rights to women, allowing both male and female heirs to inherit property. However it is wrong to say that Mitakshara deals with matters of property rights of only males as the wife is allowed to have share when husband and son partition the property.

Explanation

In order to organise his kingdom for better administration and taxation, Akbar adopted Sher Shah’s methods and principles. The Mughal administration was organized into "Subas," which were further subdivided into "Gram," "Pargana," and "Sarkar." Under Akbar’s reign, there were approximately 15 Subas, while the number increased to nearly 20 during Aurangzeb’s rule.

Option (a) is correct: The correct order according to the size is: Pargana -Sarkar-Suba. The entire Suba was split into Sarkars (districts), with a military commander known as the chief Shiqdar in charge of each one. Each Sarkar was divided into smaller units called Parganas. Each Pargana had two Karkuns (clerks or writers), one Fotahdar (treasurer), one Shiqdar (military officer), one Amin or Munsif (civilian judge).

Explanation

Copper Smelting is a process of applying heat to ore in order to extract a base metal. Smelting uses heat and a chemical reducing agent to decompose the ore, driving off other elements as gases or slag and leaving the metal base behind. It is the method of extracting pure elemental copper (Cu) from copper concentrate (CuFeS₂).

Statement 1 is incorrect: Copper smelting generally does not release lethal quantities of carbon monoxide (CO) into the environment.

Statement 2 and 3 are correct: Some smelting processes can also produce large quantities of solid waste, known as slag. This slag may leach heavy metals (arsenic, cadmium, lead or mercury depending on the composition of the ore) into groundwater reservoirs. Smelting processes are known to emit high quantities of air pollutants such as hydrogen fluoride, sulphur dioxide, oxides of nitrogen, offensive and noxious smoke fumes, vapours, gases, and other toxins.

Explanation

Under the Indian Constitution, the Directive Principles of State Policy (DPSP), found in Part IV, outline the aims and objectives that the State should strive to achieve in order to promote social and economic justice. Among these, certain principles aim to reduce economic disparities and ensure that wealth is not concentrated in the hands of a few. Article 38:The State is directed to promote the welfare of the people by securing a social order based on justice, ensuring the distribution of wealth and resources so that there are no inequalities. Article 39 (b):The State should direct its policies towards ensuring that the ownership and control of material resources are distributed in such a way that it serves the common good. Article 39 (c):The State should ensure that the economic system does not result in the concentration of wealth and means of production in the hands of a few.

Explanation

Statement 1 is correct: Furnace oil or fuel oil is a dark viscous residual product of crude-oil distillation. It is used as a fuel in different types of combustion equipment.

Statement 2 is correct: Marine engines and slow speed engines use Furnace oil for power generation, they are used for drying tea leaves. Thermic fluid heaters and hot air generators also use Furnace oil.

Statement 3 is correct: The emissions of oxides of sulphur are a direct result of the sulphur content of the fuel oil.