Solution: B

Typhoid is a bacterial infection that can lead to a high fever, diarrhea, and vomiting. It can be fatal.

It is caused by the bacteria Salmonella typhi. The infection is often passed on through contaminated food and drinking water, and it is more prevalent in places where handwashing is less frequent.

Hepatitis B is a potentially life-threatening liver infection caused by the
hepatitis B virus (HBV). It is a major global health problem. It can cause chronic infection and puts people at high risk of death from cirrhosis and liver cancer.

Malaria is a life-threatening disease. It’s typically transmitted through the bite of an infected Anopheles mosquito. Infected mosquitoes carry the Plasmodium parasite.

When this mosquito bites you, the parasite is released into your bloodstream.
Kyasanur Forest disease (KFD) is caused by Kyasanur Forest disease virus (KFDV), a member of the virus family Flaviviridae. KFDV was identified in 1957 when it was isolated from a sick monkey from the Kyasanur Forest in Karnataka (formerly Mysore) State, India. Since then, between 400-500 humans cases per year have been reported.

Hard ticks (Hemaphysalis spinigera) are the reservoir of KFD virus and once infected, remain so for life. Rodents, shrews, and monkeys are common hosts for KFDV after being bitten by an infected tick. KFDV can cause epizootics with high fatality in primates.

Solution: A

DNA and RNA

• Nucleic acids are responsible for the transfer of characters from parents to off springs. There are two types of nucleic acids — DNA and RNA.
• A nucleic acid containing deoxyribose is called deoxyribonucleic acid (DNA) while that which contains ribose is called ribonucleic acid (RNA).
• Both DNA and RNA contain Adenine, Guanine and Cytosine. The fourth base is Thymine in DNA and Uracil in RNA. Hence, statement 2 is incorrect.
• The structure of DNA is a double strand [helix] whereas RNA is a single strand molecule.
• Hydrogen bonds bind the nitrogenous bases of the two separate polynucleotide strands to make double-stranded DNA.
• The DNA backbone is resistant to cleavage, and both strands of the double-stranded structure store the same biological information. Biological information is replicated as the two strands are separated.
• Within cells, DNA is organized into long structures called chromosomes. During cell division these chromosomes are duplicated in the process of DNA replication, providing each cell its own complete set of chromosomes.
• Eukaryotic organisms (animals, plants, fungi, and protists) store most of their DNA inside the cell nucleus and some of their DNA in organelles, such as mitochondria or chloroplasts.
• In contrast, prokaryotes (bacteria and archaea) store their DNA only in the cytoplasm.

Solution: C

• Mitochondria are known as the powerhouse of the cell.
• The energy required for various chemical activities needed for life is released by mitochondria in the form of ATP (Adenosine Triphosphate) molecules.

[If Mitochondria is the Power Plant. ATP is the Electricity].

• ATP is known as the energy currency of the cell.
• The body uses energy stored in ATP for making new chemical compounds and for mechanical work.
• Mitochondria have two membrane coverings instead of just one.
• The outer membrane is very porous while the inner membrane is deeply folded. These folds create a large surface area for ATP-generating chemical reactions.
• Mitochondria are strange organelles in the sense that they have their own DNA and ribosomes. Therefore, mitochondria are able to make some of their own proteins [ribosomes prepare proteins].

Solution: A

A supernova is the explosion of a star. It is the largest explosion that takes place in space.

Where Do Supernovas Take Place?
Supernovas are often seen in other galaxies. But supernovas are difficult to see in our own Milky Way galaxy because dust blocks our view. In 1604, Johannes Kepler discovered the last observed supernova in the Milky Way. NASA’s Chandra telescope discovered the remains of a more recent supernova. It exploded in the Milky Way more than a hundred years ago.

What causes a supernova?

One type of supernova is caused by the “last hurrah” of a dying massive star. This happens when a star at least five times the mass of our sun goes out with a fantastic bang!

Massive stars burn huge amounts of nuclear fuel at their cores, or centers. This produces tons of energy, so the center gets very hot. Heat generates pressure, and the pressure created by a star’s nuclear burning also keeps that star from collapsing.

A star is in balance between two opposite forces. The star’s gravity tries to squeeze the star into the smallest, tightest ball possible. But the nuclear fuel burning in the star’s core creates strong outward pressure. This outward push resists the inward squeeze of gravity.

Solution: D

The nature of radioactive emissions

The emissions of the most common forms of spontaneous radioactive decay are the alpha (α) particle, the beta (β) particle, the gamma (γ) ray, and the neutrino. The alpha particle is actually the nucleus of a helium-4 atom, with two positive charges 4/2He. Such charged atoms are called ions. The neutral helium atom has two electrons outside its nucleus balancing these two charges. Beta particles may be negatively charged (beta minus, symbol e−), or positively charged (beta plus, symbol e+). The beta minus [β−] particle is actually an electron created in the nucleus during beta decay without any relationship to the orbital electron cloud of the atom. The beta plus particle, also called the positron, is the antiparticle of the electron; when brought together, two such particles will mutually annihilate each other.

Gamma rays are electromagnetic radiations such as radio waves, light, and X-rays. Beta radioactivity also produces the neutrino and antineutrino, particles that have no charge and very little mass, symbolized by ν and ν, respectively.

Solution: D

Solution: A

List of Operational Nuclear power plants India

Solution: B

2^nd Stage of Nuclear Program

Reactor Used – Fast breeder Reactor

Fuel – Mixture of Uranium-238 and Plutonium-239

No Moderator is needed.

Sodium is used as coolant

Pu-239 is a fissile material and on reaction this too results in extra neutrons than current chain reaction needs. These extra neutrons again are absorbed by U-238 and converted to Pu-239. At this stage more fuel is generated than is consumed. That is why it is called ‘Breeder reactor’.

This reactor doesn’t use Moderator as at high speed of neutrons only, does Pu-239 produces extra neutrons.

Further, 2^nd stage is crucial for 3rs stage as it will convert Thorium-232 (which occurs naturally) into Uranium – 233 by transmutation. This will be done in following way –

Once sufficient Power Generation capacity is achieved at 2^nd stage and there will be good reserves of Pu-239, then Th-232 will be introduced at the periphery of the core(blanket material) fuel which will be Pu-239 alone (instead of present mixture of Pu-239 & U-238). This while core fuel will be consumed and extra neutrons will be created. Again, Th-232 will get converted in U-233.

Solution: B

CERN’s main focus is particle physics – the study of the fundamental constituents of matter – but the physics programme at the laboratory is much broader, ranging from nuclear to high-energy physics, from studies of antimatter to the possible effects of cosmic rays on clouds.

Since the 1970s, particle physicists have described the fundamental structure of matter using an elegant series of equations called the Standard Model. Hence, statement 1 is incorrect.

The model describes how everything that they observe in the universe is made from a few basic blocks called fundamental particles, governed by four forces.

Physicists at CERN use the world’s most powerful particle accelerators and detectors to test the predictions and limits of the Standard Model. Over the years it has explained many experimental results and precisely predicted a range of phenomena, such that today it is considered a well-tested physics theory.

But the model only describes the 4% of the known universe, and questions remain. Will we see a unification of forces at the high energies of the Large Hadron Collider (LHC)? Why is gravity so weak? Why is there more matter than antimatter in the universe? Is there more exotic physics waiting to be discovered at higher energies? Will we discover evidence for a theory called supersymmetry at the LHC? Or understand the Higgs boson that gives particles mass?

Particles and forces

Scientists at CERN are trying to find out what the smallest building blocks of matter are.

All matter except dark matter is made of molecules, which are themselves made of atoms. Inside the atoms, there are electrons spinning around the nucleus. The nucleus itself is generally made of protons and neutrons but even these are composite objects. Inside the protons and neutrons, we find the quarks, but these appear to be indivisible, just like the electrons.

Quarks and electrons are some of the elementary particles we study at CERN and in other laboratories. But physicists have found more of these elementary particles in various experiments, so many in fact that researchers needed to organize them, just like Mendeleev did with his periodic table.

This is summarized in a concise theoretical model called the Standard Model. Today, we have a very good idea of what matter is made of, how it all holds together and how these particles interact with each other

Solution: D

What is the LHC?

The Large Hadron Collider (LHC) is the world’s largest and most powerful particle accelerator. It first started up on 10 September 2008, and remains the latest addition to CERN’s accelerator complex. The LHC consists of a 27-kilometre ring of superconducting magnets with a number of accelerating structures to boost the energy of the particles along the way.

The beams inside the LHC are made to collide at four locations around the accelerator ring, corresponding to the positions of four particle detectors – ATLAS, CMS, ALICE and LHCb.

ALICE (A Large Ion Collider Experiment) is a detector dedicated to heavy-ion physics at the Large Hadron Collider (LHC). It is designed to study the physics of strongly interacting matter at extreme energy densities, where a phase of matter called quark-gluon plasma forms.

The Large Hadron Collider beauty (LHCb) experiment specializes in investigating the slight differences between matter and antimatter by studying a type of particle called the “beauty quark”, or “b quark”.

The Compact Muon Solenoid (CMS) is a general-purpose detector at the Large Hadron Collider (LHC). It has a broad physics programme ranging from studying the Standard Model (including the Higgs boson) to searching for extra dimensions and particles that could make up dark matter. Although it has the same scientific goals as the ATLAS experiment, it uses different technical solutions and a different magnet-system design.

ATLAS is one of two general-purpose detectors at the Large Hadron Collider (LHC). It investigates a wide range of physics, from the search for the Higgs boson to extra dimensions and particles that could make up dark matter. Although it has the same scientific goals as the CMS experiment, it uses different technical solutions and a different magnet-system design.

Solution: B

Solution: D

Rare earths are a special class of 17 elements that have extensive uses across various industries including computer and IT, clean energy systems, healthcare, defence production, advanced transportation services and many others.

Significant rare earths minerals found in India include ilmenite, sillimanite, garnet, zircon, monazite and rutile, collectively called Beach Sand Minerals (BSM). India has almost 35 per cent of the world’s total beach sand mineral deposits.

Their importance lies in their unique electronic, optical and magnetic characteristics, which cannot be matched by any other metal or synthetic substitute.

Solution: A

Solution: A

According to India Met Department (IMD), the Arabian Sea arm of south-west monsoon is counting on an itinerant Madden-Julian Oscillation (MJO) wave for normal monsoon.

• It is an oceanic-atmospheric phenomenon which affects weather activities across the globe. It brings major fluctuation in tropical weather on weekly to monthly timescales.
• The MJO can be defined as an eastward moving ‘pulse’ of clouds, rainfall, winds and pressure near the equator that typically recurs every 30 to 60 days.
• It’s a traversing phenomenon and is most prominent over the Indian and Pacific Oceans.

Phases of Madden-Julian Oscillation

• The MJO consists of two parts or phases. Strong MJO activity often dissects the planet into halves. One half within the enhanced convective phase and the other half in the suppressed convective phase.
  • Enhanced rainfall (or convective) phase: winds at the surface converge, and the air is pushed up throughout the atmosphere. At the top of the atmosphere, the winds reverse (i.e., diverge). Such rising air motion in the atmosphere tends to increase condensation and rainfall.
  • Suppressed rainfall phase: winds converge at the top of the atmosphere, forcing air to sink and, later, to diverge at the surface. As air sinks from high altitudes, it warms and dries, which suppresses rainfall.
• It is this entire dipole structure, that moves west to east with time in the Tropics, causing more cloudiness, rainfall, and even storminess in the enhanced convective phase, and more sunshine and dryness in the suppressed convective phase.

How Does MJO Affect Indian Monsoon?

• The Indian Ocean Dipole (IOD), El Nino and MJO are all oceanic and atmospheric phenomena, which affect weather on a large scale. IOD only pertains to the Indian Ocean, but the other two affect weather on a global scale-up to the mid-latitudes.
• IOD and El Nino remain over their respective positions, while MJO is a traversing phenomenon.
• The journey of MJO goes through eight phases.
  • When it is over the Indian Ocean during the Monsoon season, it brings good rainfall over the Indian subcontinent.
  • On the other hand, when it witnesses a longer cycle and stays over the Pacific Ocean, MJO brings bad news for the Indian Monsoon.
• It is linked with enhanced and suppressed rainfall activity in the tropics and is very important for the Indian monsoonal rainfall.
• Periodicity of MJO:
  • If it is nearly 30 days then it brings good rainfall during the Monsoon season.
  • If it is above 40 days then MJO doesn’t give good showers and could even lead to a dry Monsoon.
  • Shorter the cycle of MJO, better the Indian Monsoon. Simply because it then visits the Indian Ocean more often during the four-month-long period.
• Presence of MJO over the Pacific Ocean along with an El Nino is detrimental for Monsoon rains.

Solution: D

Mycoremediation

• It is a form of bioremediation in which fungi are used to decontaminate the area.

Rhizofiltration is a water remediation technique that involves the uptake of contaminants by plant roots.

Rhizofiltration is used to reduce contamination in natural wetlands and estuary areas.

• Phytoextraction / phytoaccumulation is the process by which plants accumulate contaminants into the roots and above ground shoots or leaves.
• Phytotransformation or phytodegradation refers to the uptake of organic contaminants from soil, sediments, or water and their transformation to more stable, less toxic, less mobile form.
• Phytostabilization is a technique in which plants reduce the mobility and migration of contaminated soil. Leachable constituents are adsorbed and bound into the plant structure so that they form unstable mass of plant from which the contaminants will not re-enter the environment.

Solution: A

The islands of Andaman and Nicobar had the longest coastline in India, amounting to a little over 1,900 kilometers, followed by Gujarat. The state with the smallest coastline during the measured time period was the union territory of Daman and Diu. Hence, statement 2 is incorrect.

Answer: A

AIIB has more than 97 members and is open to accepting additional members.

The allocated shares are based on the size of each member country’s economy (calculated using GDP Nominal (60%) and GDP PPP (40%)), whether they are an Asian or Non-Asian Member, and the number of shares determines the fraction of authorized capital in the bank.

China is the biggest shareholder followed by India.

It has members from outside Asia such as Fiji, New Zealand etc. Membership in AIIB is open to members of the International Bank for Reconstruction and Development or the Asian Development Bank.

Answer: B

PGNRB was constituted in 2006. A number of regulatory bodies have existed before.

The board has several functions such as to provide, by regulations, and enforce, retail service obligations for retail outlets and marketing service obligations for entities; monitor transportation rates and take corrective action to prevent restrictive trade practice by the entities etc. This clearly indicates that is ensures a competitive market for gas.

The Appellate Tribunal established under section 110 of the Electricity Act, 2003 (36 of 2003) shall be the Appellate Tribunal for PGNRB.

Answer: D

VoLTE is voice calls over a 4G LTE network, rather than the 2G or 3G connections. VolTE can transmit data too. VoLTE has up to three times more voice and data capacity than 3G UMTS and up to six times more than 2G GSM.

Answer: A

The ‘Ease of Doing Business Index’ covers 10 sub-indicators including – Starting a Business, Dealing with Construction Permits, Getting Electricity, Registering Property, Getting Credit, Protecting Minority Investors, Paying Taxes, Trading Across Borders, Enforcing Contracts and Resolving Insolvency.

Solution: A

The Global Partnership on AI (GPAI) is an international initiative created by France and Canada along with Australia, the European Union, Germany, India, Italy, Japan, Mexico, New Zealand, the Republic of Korea, Singapore, Slovenia, the United Kingdom and the United States of America.

It is also multiparty and seeks to guide responsible development and use of AI in a spirit of respect for human rights, inclusion, diversity, innovation and economic growth.

In order to achieve this goal, member countries will set themselves to building bridges between theory and practice, and lend their support to cutting-edge research activities and practical implementation activities connected with AI priorities.

In collaboration with international partners and organisations, the GPAI will bring together experts from industry, civil society, governments and the academic world, who will form working groups focusing on the following themes:

• responsible use of AI;
• data governance;
• the future of work;
• innovation and commercialization

Solution: C

• Aducanumab, sold under the brand name Aduhelm, is a medication designed to treat Alzheimer’s disease.
• It is an amyloid beta-directed monoclonal antibody that targets aggregated forms of amyloid beta found in the brains of people with Alzheimer’s disease to reduce its buildup. ‘

It was developed by Biogen and Eisai.

Solution: C

Elephant Endotheliotropic Herpesvirus (EEHV)

• Elephant Endotheliotropic Herpesvirus (EEHV) is a rare viral disease that causes fatal disease in young Asian Elephants.
• When it is triggered, the elephant dies of massive internal bleeding and symptoms which are hardly visible.
• Some elephants show symptoms such as reduced appetite, nasal discharge and swollen glands.
• The disease is usually fatal, with a short course of 28-35 hours.
• It is lethal for young elephants between the ages of 1 and 12.
• There is no true cure for herpesviruses in animals or in humans.
• If a young elephant dies before reproducing, it affects the population of the species in the concerned geography.

Solution: A

Superconductivity is a phenomenon in which the resistance of the material to the electric current flow is zero.

Because of zero resistance, superconducting materials can save huge amounts of energy, and be used to make highly efficient electrical appliances.

Superconductivity is largely possible at low temperature.

Metallic superconductors usually have transition temperatures (temperatures below which they are superconductive) below 30 K (−243.2 °C) and must be cooled using liquid helium in order to achieve superconductivity.

Solution: A

Danube River is  the second longest in Europe after the Volga. It rises in the Black Forest mountains of western Germany and flows for some 1,770 miles (2,850 km) to its mouth on the Black Sea.

Croatia is located in Central and Southeast Europe, on the coast of the Adriatic Sea. It borders Hungary to the northeast, Serbia to the east, Bosnia and Herzegovina and Montenegro to the southeast, and Slovenia to the northwest.

Italy is one of the largest European countries in the Mediterranean and has a land border that stretches 1,116 miles in length. France, Switzerland, Austria, and Slovenia are the four countries that share a land border with Italy.

Ans. A.

A is correct as the passage states that whenever humans have dominated an ecosystem, other animals have disappeared which proves A.

Ans. B.

The central focus of the passage is on the LWEs who are fighting an ideological battle, where their ideology is guilty of the same crimes as the ideology they are fighting for. Hence B.

Answer: (d)

Justification:

Correct Option: D

Neither of the statements is independently sufficient as the average age and the strength of different classes are mentioned in two different statements.

Combining both the statements, even if the class VIII forms 25% of the total strength, the average age will be less than 17 years.

This is shown below:

Let the strength of the school be 10k and that of the class VIII students be 2.5k. In that case the strength of the remaining classes is 7.5k. Hence, the average age of the school

→        (2.5k × 18 + 7.5k × 16)/10K = 16.5 years

Hence, the average age will be less than 17 years. If the strength of the VIII class is less than 25%, the average age would be less than 16.5 years.

Hence, option D is correct.

Solution: C

Explanation: