Solution (b)

Notes:

Adaptations are found in the natural world among animals, which help them in surviving in their habitat.

Other adaptations found in the animals- are-

Polar bears –

• They also have a layer of fat under their skin. They are so well-insulated that they have to move slowly and rest often to avoid getting overheated. Physical activities on warm days necessitate cooling. So, the polar bear goes for swimming.
• They have a strong sense of smell so that they can catch their prey for food.

Penguins –

• They also have a thick skin and a lot of fat to protect them from cold. Like polar bears, penguins are also good swimmers. Their bodies are streamlined and their feet have webs, making them good swimmers.

Solution (c)

Notes:

 Examples of different Interactions:

Mutualism:

1. Humans and Plants:

The human requires oxygen for life and plants use the carbon dioxide for photosynthesis. Here both human and plants are mutually benefited. Humans use the oxygen given by the plants. In return, plants use carbon dioxide, which is exhaled by the Humans.

2. Oxpeckers and Rhinos:

The bird oxpecker lives on the rhino and removes all bugs and parasites on the animal skin by eating them. The Rhino provides the bird with food and in return, the bugs removed from the skin of the rhino. Both rhino and the oxpecker are benefited.

Competition:

An example among animals could be the case of Cheetah and lions since both species feed on similar prey, they are negatively impacted by the presence of the other because they will have less food, however they still persist together, despite the prediction that under competition one will displace the other.

Predation:

Tiger (predator) eating deer (prey), frog eating insects

Parasitism:

Among the animals, ticks, mites and lice are external parasites or ectoparasites.

The fungal parasites include Erysiphe (powdery mildew), Ustilago (smut), Puccinia (rust), etc.; which cause diseases that result in serious losses of economically important crops.

Commensalism:

Association between suckerfish (or Remora or Echeneis) and shark-

The sucker fish has the dorsal fin modified as a sucker(or adhesive) disc, with the help of which it is attached to the body of shark so that the suckerfish gets free transportation.

The sucker fish releases the attachment after sometime and swims in search of food.

Ammensalism:

When cattle trample on grass, the grass is crushed. However, the cattle do not benefit from this action nor is harmed in the process.

Solution (c)

Solution (a)

Notes:

Biomagnifications-

• It refers to the tendency of pollutants to concentrate as they move from one trophic level to the next.
• In biomagnifications there is an increase in concentration of a pollutant from one link in a food chain to another. In order for biomagnifications to occur, the pollutant must be:
• long-lived
• Mobile
• soluble in fats
• Biologically active
• It can be seen in the case of Mercury or DDT. The concentration of Mercury/DDT increases at the successive trophic levels. DDT concentration in zooplankton gets magnified when DDT contaminated water is consumed by the Zooplanktons. In the successive trophic levels like, small fish, big fish, and at top carnivore, the magnification is much higher, which proves the event of Biomagnifications.
• A pollutant having properties like long life, mobile, soluble in fat, biologically active will lead to the process of biomagnifications.

Solution (b)

 Note:

The total amount or weight, or energy content, of (a portion of) organisms existing in a specific area at a particular time, is known as standing crop.

The non-living (inorganic nutrients) like carbon, nitrogen, phosphorus etc. present in the soil at that time is called the standing state.

Solution (c)

Solution (c)

Notes:

Invasive Species-

• Invasive species have devastating effects on wildlife.
• Human health and economies are also at risk from invasive species. Many of our commercial, agricultural, and recreational activities depend on healthy native ecosystems.
• Species that grow and reproduce quickly, and spread aggressively, with potential to cause harm, are given the label “invasive.”
• An invasive species does not have to come from another country.
• Invasive species are primarily spread by human activities, often unintentionally. People, and the goods we use, travel around the world very quickly, and they often carry uninvited species with them.
• When a new and aggressive species is introduced into an ecosystem, it may not have any natural predators or controls.
• It can breed and spread quickly, taking over an area. Native wildlife may not have evolved defenses against the invader, or they may not be able to compete with a species that has no predators.
• One way to curb the spread of invasive species is to plant native plants and remove any invasive plants in your garden.
• Examples if Invasive Species in India:
  • Alternanthera philoxeroides
  • Cassia uniflora
  • Chromolaena odorata
  • Eichhornia crassipes
  • Lantana camara
  • Parthenium hysterophorus
  • Prosopis juliflora etc

Solution (d)

Notes:

Nitrogen fixation-

• Plants need nitrogen to make themselves. Without nitrogen, a plant cannot make the proteins, amino acids and even its very DNA.
• This is why when there is a nitrogen deficiency in the soil, plants are stunted. They simply cannot make their own cells. If there is nitrogen all around us, as it makes up 78 percent of the air we breathe.
• In order for plants to use the nitrogen in the air, it must be converted in some way to nitrogen in the soil. This can happen through nitrogen fixation, or nitrogen can be ‘recycled’ by composting plants and manure.
• There are two routes to go when fixing a nitrogen deficiency in the soil, either organic or non-organic.
• Organic:

To correct a nitrogen deficiency using organic methods requires time, but will result in a more even distribution of the added nitrogen over time.

• Adding composted manure to the soil
• Planting a green manure crop, such as borage Planting
• nitrogen fixing plants like peas or beans
• Adding coffee grounds to the soil

• Non-Organic:

Using a nitrogen fertilizer to fix a nitrogen deficiency in the soil will give a big, fast boost of nitrogen to the soil, but will fade quickly.

Solution (c)

Coastal Regulation Zone:

CRZ along the country has been placed in four categories, which are as follows:

1. CRZ I – Ecologically Sensitive Areas

• They lie between low and high tide line.
• Exploration of natural gas and extraction of salt are permitted.

2. CRZ II – Shore Line Areas

• The areas that have been developed up to or close to the shoreline.
• Unauthorized structures are not allowed to construct in this zone.

3. CRZ III – Undisturbed Area

• Rural and Urban localities which fall outside I and II.
• Only certain activities related to agriculture even some public facilities are allowed in this zone.

4. CRZ IV – Territorial Area

• An area covered between Low Tide Line and 12 Nautical Miles seaward.
• Fishing and allied activities are permitted in this zone.
• Solid waste should be let off in this zone.

Changes made to the regulatory framework-

• The system of granting clearances has been changed. States will have the authority to approve proposals for urban (CRZ-II) and rural (CRZ-III) areas.
• The Ministry of Environment, Forests and Climate Change will grant clearances for ecologically sensitive areas (CRZ-I), and areas falling between the low tide line and 12 nautical miles seaward.
• The modifications also include demarcation of a 20-metre no development zone for all islands and guidelines to deal with sensitive areas.

Solution (c)

Notes:

Organic farming-

Organic farming is a holistic system designed to optimize the agricultural productivity and to reduce the impacts on diverse communities like soil organisms, plants, livestock and humans. Organic farming is a contemporary method of crop and livestock production that involves tools which do not use chemicals and artificial tools of cropping. It is an integrated farming system that strives for sustainability, enhancement of soil fertility and biological diversity.

Key characteristics of organic farming are:

• It relies primarily on local, renewable resources
• It makes efficient use of solar energy and the production potential of biological systems
• It maintains the fertility of the soil
• It maximizes recycling of plant nutrients and organic matter
• It does not use organisms or substances foreign to nature (e.g GMOs, chemical fertilizers or pesticides)

Substances which are prohibited in organic farming are:

• Chemical fertilizers and pesticides
• Genetically modified organisms
• Nanomaterials

Solution (b)

Note:

Seed Bank-

• A seed bank is a kind of gene bank that stores seeds of food crops or any rare species of plants. Seed banks protect us against the extinction of plant species due to natural catastrophes, outbreak of diseases and even deliberate non-use for a long time. Seed banks make our diminishing biodiversity available to future generations.
• Seeds in a seed bank are dried to suitably low moisture content and stored at -18°C or below. The bank also documents the plan’s identity, sampling location, seed quantity, farming systems in which the crop was grown etc.
• Svalbard Global Seed Vault is a facility on a remote island in the Arctic Ocean and it houses the world’s largest collection of seeds. The seeds can be used in event of global catastrophe or when some species is lost due to natural disasters; hence it called the doomsday vault.
• India’s seed vault is located at Chang La, Ladakh in the Himalayas which stores over 5000 seed accessions (One accession consists of a set of seeds of one species collected from different locations or different populations).
• The vault is a joint venture of National Bureau of Plant Genetic Resources (which comes under Indian Council of Agriculture Research) and the Defense Institute of High-Altitude Research (under Defense Research and Development Organization).

Solution (d)

Note:

ZBNF is based on 4 pillars:

• Jeevamrutha: It is a mixture of fresh cow dung and aged cow urine (both from India’s indigenous cow breed), jaggery, pulse flour, water and soil; to be applied on farmland.
• Bijamrita: It is a concoction of neem leaves & pulp, tobacco and green chilies prepared for insect and pest management, that can be used to treat seeds.
• Acchadana (Mulching): It protects topsoil during cultivation and does not destroy it by tilling.
• Whapasa: It is the condition where there are both air molecules and water molecules present in the soil. Thereby helping in reducing irrigation requirement.

Solution (a)

Solution (b)

Solution (c)

Solution (c)

Critically Endangered Category:

A species is categorized as Critically Endangered when it meets any of the following criteria:

1. Reduction in the population of more than 90% over the last 10 years.
2. The population size is less than 50 mature individuals.
3. Quantitative analysis showing the probability of extinction in the wild in at least 50% in their 10 years.

Solution (c)

Note: Osmoregulation involves active regulation of the water content within a living system irrespective of the water content of the surrounding environment. Different species of organisms use different mechanisms for osmoregulation.

• Therefore, in the context of osmoregulation, species could be divided into two categories; osmoconformers and osmoregulators.
• Under osmoconformers, stenohaline organisms are included, and under osmoregulators euryhaline organisms are included.
• Euryhaline organisms have the ability to survive in varying concentrations of salts while stenohaline organisms thrive at a limited range of salinity.
• This is the difference between euryhaline and stenohaline.

Solution (d)

Note:

Bioremediation:

• Bioremediation is the use of microorganisms (bacteria and fungi) to degrade the environmental contaminants into less toxic forms.
• The microorganisms may be indigenous to a contaminated area or they may be isolated from elsewhere and brought to the contaminated site.
• The process of bioremediation can be monitored indirectly by measuring the Oxidation Reduction Potential or redox in soil and groundwater, together with pH, temperature, oxygen content, electron acceptor/donor concentrations, and concentration of breakdown products (e.g., carbon dioxide)

In-Situ Bioremediation:

• In Situ — It involves treatment of the contaminated material at the site.
• Bioventing: Supply of air and nutrients through wells to contaminated soil to stimulate the growth of indigenous bacteria. It is used for simple hydrocarbons and can be used where the contamination is deep under the surface.
• Biosparging: Injection of air under pressure below the water table to increase groundwater oxygen concentrations and enhance the rate of biological degradation of contaminants by naturally occurring bacteria
• Bioaugmentation: Microorganisms are imported to a contaminated site to enhance degradation process.
• Using bioremediation techniques, TERI has developed a mixture of bacteria called ‘Oilzapper and Oilivorous-S’ which degrades the pollutants of oil-contaminated sites, leaving behind no harmful residues. This technique is not only environment friendly, but also highly cost-effective.

Ex Situ Bioremediation:

• Ex Situ — involves the removal of the contaminated material to be treated elsewhere.
• Land Farming: contaminated soil is excavated and spread over a prepared bed and periodically tilled until pollutants are degraded. The goal is to stimulate indigenous biodegradative microorganisms and facilitate their aerobic degradation of contaminants.
• Biopiles: it is a hybrid of land farming and composting. Essentially, engineered cells are constructed as aerated composted piles. Typically used for treatment of surface contamination with petroleum hydrocarbons.
• Bioreactors: it involves the processing of contaminated solid material (soil, sediment, sludge) or water through an engineered containment system.
• Composting: Composting is nature’s process of recycling decomposed organic materials into a rich soil known as compost.

Solution (b)

Note:

Oil Spill:

• An oil spill refers to an uncontrolled release of gasoline, crude oil, other oil products, and fuels into the environment. An oil spill can pollute water, air, and land by destroying natural habitats.
• The production on continental shelves, petroleum exploration, and transportation in large vessels have increased the cases of oil spills.
• According to Marine Insight, nearly 706 million gallons of waste oil pollute the ocean every year. Oil waste disposal and land drainage practices increase pollution levels in water bodies.
• Ideally, accidents involving pipelines, oil tankers, or drilling rigs are the primary causes of oil spills in oceans, rivers, and bays.
• Students preparing for UPSC prelims and IAS exams should know the impact of oil spills on the environment.

Impact of Oil Spill on the Environment and Humans:

• Oil spill causes health hazards to natives depending on seafood.
• Crude oil destroys the insulating capacity of bird feathers and coats them will oil. Marine life and bird coated in oil are prone to hypothermia and death.
• Oil forms a thin layer on the ocean surfaces and prevents sufficient sunlight from entering the ocean surface. This reduces the dissolved oxygen levels in water, making it difficult for marine life to breathe.
• Oil spills at sea increase the Chemical oxygen demand (COD) in the water and cause harm to the organisms.
• Ingesting toxic animals or preys kills predators, ultimately destroying the reproductive rate and habitat.
• Mangroves and saltwater marshes that protect the earth from natural disasters are prone to significant oil spills. This can be dangerous for the environment.

Solution (a)

Notes:Forest Fires:

Forest fires are uncontrolled fires that burn surface vegetation.

Forest fires cause following adverse impacts:

• Loss of valuable timber resources.
• Depletion of carbon sinks.
• Degradation of water catchment areas resulting in loss of water.
• Loss of biodiversity and extinction of plants and animals.
• Loss of wildlife habitat and depletion of wildlife.
• Loss of natural regeneration and reduction in forest cover and production.
• Global warming resulting in rising temperature.
• Loss of carbon sink resource and an increase in the percentage of CO2 in the atmosphere.
• Change in the microclimate of the area making it unhealthy living conditions.
• Soil erosion affecting the productivity of soils and production.
• Ozone layer depletion.
• Health problems leading to diseases.
• Indirect effects on agricultural production leading to loss of livelihood.

Solution (c)

• Context: The Union Health Ministry has made available generic drugs for rare diseases for the first time. Presently, they are made available for four rare diseases Tyrosinemia-Type 1, Gauchers Disease, Wilson’s Disease, and the Dravet-Lennox Gastaut Syndrome.
• There is no universally accepted definition of rare diseases; However, the World Health Organisation (WHO) defines rare disease as often debilitating lifelong disease or disorder condition with a prevalence of one or less per 1,000 population. Indian Council of Medical Research (ICMR) defines rare disease as a disease with one occurrence in 2,500 people.
• Gaucher disease is the result of a build-up of certain fatty substances in certain organs, particularly in the spleen and liver. Hence statement 1 is correct.
• Tyrosinemia type I is an inherited metabolic disorder in which the body lacks an enzyme called fumarylacetoacetate hydrolase (FAH). Hence statement 2 is correct.
• FAH is needed to break down the amino acid tyrosine.
• Wilson’s disease is an inherited disorder that is caused by abnormal copper accumulation in your liver, brain, and other vital organs. Hence statement 3 is correct.
• Dravet-Lennox gastaut syndrome is a rare drug-resistant epileptic condition, characterised by seizures.

Solution (b)

• The backwaters of the Nugu dam form part of the sanctuary.
• It is a part of the Nilgiri Biosphere Reserve located in Karnataka. Hence statement 1 is incorrect.
• It is located near Bandipur Tiger Reserve.
• It has been declared an eco-sensitive zone by the Ministry of Environment, Forests and Climate Change. Hence statement 2 is correct.
• Its fauna includes tiger, elephant, leopard, wild dog, striped hyena, sloth bear, gaur, sambhar, chital, and four-horned antelope. In addition, the sanctuary also harbours two important riverine wildlife species, – the smooth-coated otter and the marsh crocodile.
• Its vegetation includes southern mixed deciduous forest and dry deciduous scrub forest. Hence statement 3 is correct.
• The Nugu Wildlife Sanctuary receives rainfall both from southwest and northeast monsoons.

Solution (b)

• Budapest Convention on Cybercrime is the first international treaty that seeks to address Internet and cybercrime by harmonizing national laws and India is not a signatory to this convention. Hence statement 1 is incorrect.
• The CERT-IN (Computer Emergency Response Team- India) is the national nodal agency for responding to computer security incidents or cyber security threats. Hence statement 2 is correct.
• CERT-IN was formed in 2004 by the Government of India under Information Technology Act, 2000 Section (70B).
• The Ministry of Electronics and Information Technology (MeitY) is its nodal ministry. Its vision is a proactive contribution to securing India’s cyberspace.

Solution (b)

• Under Article 233, district court judges are appointed by the Governor of the State in consultation with the High Court exercising jurisdiction in relation to such State.
• The judges of a high court are appointed by the President. Hence statement 1 is incorrect.
• All India Judicial Service (AIJS) is a reform that aims to centralize the recruitment of judges at the level of additional district judges and district judges for all states. Hence statement 2 is correct.
• The original constitution didn’t provide for the creation of an All India Judicial Service (AIJS).
• All India Judicial Service (AIJS) was first proposed by the Law Commission’s 1958 ‘Report on Reforms on Judicial Administration’. Hence statement 3 is correct.
• Article 312 was amended by the 42nd Constitution (Amendment) Act, 1976 to provide for an AIJS by a Parliamentary law. It enables the creation of the AIJS at the District Judge level.

Solution (b)

• The Indian Ocean Tuna Commission is an intergovernmental organization responsible for the management of tuna and tuna-like species in the Indian Ocean. Hence statement 1 is incorrect.
• It was established in 1993 and came into force in 1996.
• It seeks to do this by promoting cooperation among its contracting parties (members) and cooperating with non-contracting parties in order to ensure the conservation and appropriate utilisation of fish stocks and encourage the sustainable development of fisheries.
• The decisions taken by the commission are binding on all members and non-contracting parties. Hence statement 2 is correct.
• It has 30 contracting parties (India joined as a member in 1995) and Liberia is a cooperating non-contracting party.
• Its headquarters are located in Victoria, Seychelles. Hence statement 3 is correct.

Solution (c)

• Psyche Spacecraft is a NASA space mission to explore the origin of planetary cores by orbiting and studying the asteroid 16 Psyche. Hence statement 1 is incorrect.
• Scientists believe this asteroid is the nickel-iron core of an early planet, studying which could provide unique insights into the impenetrable iron core of our own planet.
• It is managed by the Jet Propulsion Laboratory (JPL) of NASA. Hence statement 2 is correct.
• The spacecraft will not land on the asteroid but will orbit it from August 2029 through late 2031.
• It is the first mission to use laser optical communications beyond the Earth-Moon system. Hence statement 3 is correct.
• The Psyche mission is expected to provide critical insights into the formation and evolution of our solar system.
• It is the first interplanetary spacecraft to use solar-powered hall effect thrusters for propulsion and orbital manoeuvring. Hence statement 4 is correct.

Solution (c)

• The International Labour Organization (ILO) has eight core conventions. India has ratified six conventions out of eight conventions. They are:
• Forced Labour Convention (No. 29)
• Abolition of Forced Labour Convention (No.105)
• Equal Remuneration Convention (No.100)
• Discrimination (Employment Occupation) Convention (No.111)
• Minimum Age Convention (No.138)
• Worst forms of Child Labour Convention (No.182)

• ILO core conventions not ratified by India:
• Freedom of Association and Protection of Right to Organised Convention (No.87)
• Right to Organize and Collective Bargaining Convention (No.98)

Hence option c is correct.

Solution (d)

• The axolotl’s name is derived from the Latin words “atl” (water) and “xolotl” (the Aztec god of fire and lightning, who could take on the form of a salamander).
• Axolotl are neotenic species of salamander. Hence statement 1 is correct.
• Salamanders are a group of amphibians.
• They are neotenic which means they keep juvenile characteristics into adulthood. They retain juvenile features such as gills, tails, and a preference for living in water.
• They are classified as critically endangered in the IUCN List. Hence statement 2 is correct.
• The population density of Mexican Axolotl has reduced by 99.5% in under two decades.
• They can regenerate lost or damaged limbs, hearts, lungs, and even parts of their brains.
• They remain underwater throughout their life. Hence statement 3 is correct.
• Axolotl is a cultural icon in Mexico for their unique slimy appearance and for their ability to regrow limbs.
• They are found in Mexico City’s Lake Xochimilco. Hence statement 4 is correct.

Solution (b)

The key findings of UNEP’s Emissions Gap Report 2023:

• The world is heading towards a 3°C temperature rise by 2100, compared to pre-industrial levels. Hence statement 1 is incorrect.
• Global emissions rose by 1.2% in 2022 from 2021, nearly returning to pre-pandemic levels.
• This fourteenth Emissions Gap Report is published ahead of the twenty-eighth session of the Conference of the Parties to the United Nations Framework on Climate Change (COP 28). Hence statement 2 is correct.
• The 2016 edition of the report had projected a warming of up to 3.4 degrees Celsius in a business-as-usual scenario. However, according to the Emissions Gap Report 2023, the current projection for the increase in emissions by 2030 is about 3%. Still, this is not enough to meet the 1.5°C target.
• To limit global warming to 2°C, emissions must be cut by 28% by 2030 and by 42% by 2030 for the 1.5°C target. Hence statement 3 is correct.

Solution (c)

• The Amplifi 2.0 Portal was launched by the Ministry of Housing and Urban Affairs. Hence statement 1 is correct.
• Amplifi – Assessment and Monitoring Platform for Liveable, Inclusive, and Future-Ready Urban India portal.
• The portal provides data on various services for several cities such as:

• Total diesel consumption
• Number of water quality samples tested
• Average annual healthcare expenditure
• Total population residing in slums
• Recorded fatalities from road accidents

• It aims to make raw data from Indian cities available on a single platform for academics, researchers, and stakeholders to help data-driven policymaking. Hence statement 2 is correct.
• Currently, 258 urban local bodies have been onboarded and data for 150 cities is accessible on the platform.
• Eventually, data from the more than 4,000 Urban Local Bodies will be made available on the portal.

Note:

• According to the 2011 Census, 37.7 crore people (31% of the population) lived in urban areas. By 2030, this is projected to increase by 60 crores or 40%.
• In 2011, urban areas contributed 63% to the country’s GDP and this is projected to increase to 75% by 2030.

Solution (b)

Let x and y be speeds of two joggers (km/min) and d be the distance.

According to given data,

42x + 1 = d …(1)

52y + 2 = d …(2)

d/y – d/x = 17 …(3)

Solving (1), (2) & (3),

x = 1/3 km/min

y = 1/4 km/min

d = 15 km

Distance between Delhi and Noida is 15 km.

Solution (c)

In the first hour, they cover 6km.

In the second hour they cover 6.5km.

In the third hour, they cover 7km and so on. Finally, they cover 72km in 9 hours.

Distance covered by A in 9 hours = 4*9 = 36kms

They meet mid-way between A and B.

Solution (b)

Number of candidates who had none of the three = Total number of candidates – the number of candidates who had at least one of three devices.

The total number of candidates = 1300.

We know that, Total= A + B + C – {A ∩ B + B ∩ C + C ∩ A + 2(A ∩ B ∩ C)} + neither

Therefore, 1300 = 900 + 630 + 690 – {300 + 360 + 230 +200} + neither

=> Neither = [1300 −(900 + 630 +690) + (300 + 360 + 230 +200)]

The number of candidates having neither = 170

Solution (c)

N1 = 247x + 17 and N2 = 361y + 52

N1 + N2 = (19 × 13 × x + 17) + (19 ×19 × y + 52)

Remainder when N1 + N2 is divided by 19, = (17+52)/19 = 12

Solution (c)

Total present age of the family (6*20) = 120 years

Total age of the family 5 years ago = (120 – 6*5) = 90 years

At that time, Total members in the family = 5

Therefore Average age at that time = 90/5 = 18 years