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GS Paper: GS3-17.Awareness in the fields of IT, Space, Computers, Robotics, Nano-technology, Bio-technology and issues relating to Intellectual Property Rights.

  • [pib] PRATUSH Mission

    Why in the News?

    Raman Research Institute (RRI) has devised the Probing ReionizATion of the Universe using Signal from Hydrogen (PRATUSH) Telescope to study the “Cosmic Dawn” by detecting radio signals from neutral hydrogen gas.

    About the PRATUSH Mission:

    • Developer: Designed by the Raman Research Institute (RRI), Bengaluru, an autonomous institute under the Department of Science and Technology (DST).
    • Main Goal: To study the Cosmic Dawn – the period when the first stars and galaxies formed – by detecting the faint 21-cm radio signal from neutral hydrogen.
    • Why from the Moon? On Earth, these signals get lost due to radio noise (like FM signals) and atmospheric distortions. The lunar far side is the quietest place in the inner Solar System for radio astronomy, making it the best site.
    • Scientific Importance: Will help scientists understand how the first stars heated and ionized hydrogen gas, how the early Universe changed, and may even give clues about dark matter and fundamental physics.

    Key Features:

    • Compact Design: Small, lightweight, low-power, and cost-effective – in line with the global trend of miniaturized space instruments.
    • Digital Receiver System:
      • Uses a single-board computer (like Raspberry Pi prototype).
      • Equipped with FPGA (Field Programmable Gate Array) for high-speed radio data processing.
    • How it Works:
      • Antenna collects faint hydrogen signals.
      • Analog receiver amplifies them.
      • Digital receiver + FPGA convert them into detailed spectral fingerprints of sky brightness.
    • Test Results: Lab trials (352 hours) showed extremely low noise (few millikelvins), proving it can detect faint cosmic signals.
    • SWaP Advantage: Optimized for Size, Weight, and Power (SWaP), making it highly suitable for space deployment.
    [UPSC 2010]  In the context of space technology, what is Bhuvan, recently in the news?

    Options:

    (a) A mini satellite launched by ISRO for promoting the distance education in India

    (b) The name given to the next Moon Impact Probe, for Chandrayaan-II

    (c) A geoportal of ISRO with 3D imaging capabilities of India *

    (d) A space telescope developed by ISRO

     

  • NASA-ESA Solar Orbiter Mission

    Why in the News?

    The NASA-ESA Solar Orbiter Mission has recently traced the origin of Solar Energetic Electrons (SEE), advancing knowledge of solar activity and space weather.

    NASA-ESA Solar Orbiter Mission

    About NASA–ESA Solar Orbiter Mission:

    • Launch & Cost: Launched in Feb 2020 on an Atlas V from Cape Canaveral; joint ESA–NASA mission worth $1.5 billion.
    • Duration: Primary mission till 2026, extendable to 2030.
    • Orbit: Highly eccentric, approaching 0.28 AU (inside Mercury’s orbit); gradually tilts to image Sun’s poles.
    • Payload: 10 instruments — both in-situ (solar wind, magnetic fields, particles) and remote sensing (imaging, spectroscopy).
    • Firsts & Objectives: First to image solar poles; aims to study solar wind origin, solar cycle dynamics, causes of flares/CMEs, and their impact on heliosphere & space weather.

    What are Solar Energetic Electrons (SEE)?

    • What are they: Streams of high-energy electrons released into space, travelling across the heliosphere.
    • Sources: Emerge from solar flares (sudden surface bursts) and coronal mass ejections (CMEs) (plasma + magnetic eruptions).
    • Patterns: Release not always immediate; often delayed by hours due to turbulence/scattering in interplanetary medium.
    • Solar Orbiter Observations: Detected 300+ bursts (2020–22), clearly linking SEE to solar flares/CMEs for the first time.

    Significance of the recent findings:

    • Science: Clarifies Sun’s particle acceleration mechanisms.
    • Space Weather: CMEs are the main drivers of severe events — affecting satellites, GPS, communication, power grids, and astronaut safety.
    • Practical Utility: Improves solar storm forecasting and early-warning systems for infrastructure & human spaceflight.
    • Long Term Implications: Expected to revolutionise solar physics and our predictive capacity of Sun–Earth interactions.
    [UPSC 2022] If a major solar storm (solar flare) reaches the Earth, which of the following are the possible effects on the Earth?

    1. GPS and navigation systems could fail.

    2. Tsunamis could occur at equatorial regions.

    3. Power grids could be damaged.

    4. Intense auroras could occur over much of the Earth.

    5. Forest fires could take place over much of the planet.

    6. Orbits of the satellites could be disturbed.

    7. Shortwave radio communication of the aircraft flying over polar regions could be interrupted.

    Select the correct answer using the code given below:

    (a) 1, 2, 4 and 5 only (b) 2, 3, 5, 6 and 7 only (c) 1, 3, 4, 6 and 7* only (d) 1, 2, 3, 4, 5, 6 and 7

     

  • Jarosite in Kutch: India’s Mars Analogue Site

    Why in the News?

    Matanomadh in Kutch, Gujarat, with jarosite deposits like those on Mars, is being considered by ISRO as a test site for future Mars missions.

    What is Jarosite?

    • Composition: A yellow, iron-rich sulphate mineral containing iron, sulphur, oxygen, and potassium.
    • Formation: Develops when volcanic ash or sulphur-bearing minerals chemically react with water, making it a marker of past water–rock interaction.
    • Discovery in India: Reported in 2016 at Matanomadh, Kutch (Gujarat) by ISRO’s Space Applications Centre; also found at Varkala cliffs, Kerala. Kutch is more suitable for planetary research.
    • Martian Link: Detected in 2004 by NASA’s Opportunity Rover. This referred as terrestrial clone of Martian surface.
    • Global Occurrence: Found in Mexico, Spain, Canada, Japan, and the USA (Utah, California), all serving as Mars analogue sites.

    Matanomadh’s Significance for Mars Study:

    • Mars Analogue Value: Geological dating shows deposits about 55 million years old (Paleocene period), resembling early Martian conditions.
    • Test Bed for ISRO: Provides ground for testing rover mobility, drilling systems, geochemical studies, and remote sensing for Mangalyaan-2 and future missions.
    • Astrobiology Potential: Since jarosite can trap organic molecules, it helps in shaping strategies to search for signs of past life on Mars.
    • Complement to Ladakh: While Ladakh sites simulate Martian climate, Matanomadh represents Martian geology and mineralogy, creating a comprehensive Mars-analogue ecosystem in India.
    • Conservation Importance: Facing threats from waterlogging and coal mining; scientists urge its declaration as a Planetary Geo-heritage Site.
    • Strategic Edge: Strengthens India’s role in planetary exploration, astrobiology research, and international collaborations.
    [UPSC 2016] Consider the following statements:

    1. The Mangalyaan launched by ISRO

    2. is also called the Mars Orbiter Mission

    3. made India the second country to have a spacecraft orbit the Mars after USA

    4. made India the only country to be successful in making its spacecraft orbit the Mars in its very first attempt

    Which of the statements given above is/are correct?

    (a) 1 only   (b) 2 and 3 only   (c) 1 and 3 only * (d) 1, 2 and 3

     

  • Kulasekarapattinam Launch Complex

    Why in the News?

    ISRO Chairman V. Narayanan announced that the upcoming rocket launching site at Kulasekarapattinam (Tamil Nadu) will handle 20–25 satellite launches annually.

    Kulasekarapattinam Launch Complex

    About Kulasekarapattinam Spaceport:

    • Location: Coastal hamlet near Tiruchendur, Thoothukudi district, Tamil Nadu; inaugurated by PM in February 2024.
    • Second Spaceport: India’s second spaceport after Satish Dhawan Space Centre (Sriharikota, Andhra Pradesh, 1971).
    • Capacity: Can handle 20–25 launches annually, including 24 launches using a Mobile Launch Structure.
    • Focus: Dedicated to Small Satellite Launch Vehicles (SSLVs), with capacity to launch rockets up to 500 kg.
    • Facilities: About 35 facilities including launch pad, rocket integration units, ground range, checkout systems, and Mobile Launch Structure with onboard checkout computers.

    Advantages offered by Kulasekarapattinam Spaceport:

    • Direct Southward Launches: Location allows launches into the Indian Ocean without crossing landmasses; ensures more safety from debris fall.
    • No Dogleg Manoeuvre: Unlike Sriharikota, no detour is needed to avoid Sri Lanka, saving fuel.
    • Efficient Trajectory: Improves efficiency for satellites in Sun-Synchronous Polar Orbits (SSPOs).
    • Payload Advantage: SSLVs from Kulasekarapattinam can place ~300 kg into SSPO, higher than from Sriharikota.
    • Decongestion: Reduces pressure on Sriharikota, which will focus on larger PSLV, GSLV, and Gaganyaan launches.
    • Commercial Boost: Strengthens India’s role in the global small-satellite launch market, enhancing space economy.
    • Strategic Advantage: Near-equator position provides benefits for certain orbital paths.
    [UPSC 2008] ISRO successfully conducted a rocket test using cryogenic engines in the year 2007. Where is the test-stand used for the purpose, located?

    Options: (a) Balasore (b) Thiruvananthapuram (c) Mahendragiri* (d) Karwar

     

  • With Sci-Hub gone, will the ‘One Nation, One Subscription’ scheme step up?

    Introduction

    The blocking of Sci-Hub in India marks a turning point in the battle between corporate publishers and the principle of open knowledge. At the heart of the issue lies the paradox of publicly funded research locked behind exorbitant paywalls. The government’s One Nation One Subscription (ONOS) scheme, with an allocation of ₹6,000 crore, aims to democratize access to 13,000 journals for research institutions. Yet, concerns remain about its cost-effectiveness, inclusivity, and long-term sustainability.

    Why is this issue in the news?

    • The Delhi High Court’s verdict against Sci-Hub is a landmark moment because:
    • For the first time in India, the judiciary has formally sided with publishers in the long-drawn copyright battle.
    • It stands in sharp contrast with the reality that research is funded by public money but monetized by private publishers with 30%+ profit margins.
    • The problem is enormous: lakhs of rupees per journal subscription make access unaffordable for many institutions, forcing dependence on Sci-Hub earlier.
    • The government’s ONOS initiative is the first large-scale attempt to address structural inequities in knowledge access, but doubts persist about its ability to replace shadow libraries.

    The Distinctive Nature of Scientific Publishing

    1. No royalties for authors: Researchers and peer reviewers are unpaid, unlike musicians or filmmakers.
    2. Publicly funded research: Much of Indian science is taxpayer-funded, yet access is privatized.
    3. Exorbitant subscriptions: Institutions pay lakhs for a single journal. Publishers justify costs via “quality control” but enjoy 30%+ profit margins, raising concerns of rent-seeking.

    The Global Controversy Around Sci-Hub

    1. Copyright infringement: Courts in the U.S., Europe, and now India have ruled against Sci-Hub.
    2. Essential access tool: For countless researchers, Sci-Hub was the only means to access knowledge, especially outside elite universities.
    3. Contempt charges: Alexandra Elbakyan allegedly violated court orders by running Sci-Net, a mirror service.
    4. Declining relevance: Technical unreliability and growing open-access alternatives are reducing its utility.

    The Vision of One Nation, One Subscription

    1. Government-led subscription: Outlay of ₹6,000 crore (2023–2026) for bulk access to 13,000 journals.
    2. Phase I focus: All public institutions; Phase II may include private ones.
    3. Equal access: Seeks to eliminate inequities between elite and smaller research centres.
    4. Limitations: Independent researchers and those at private centres remain excluded until Phase II.

    ONOS in the Context of Global Open-Access Movements

    1. Global open-access movement: Over half of papers are already open access through preprints and repositories.
    2. U.S. policy (2026): All federally funded research must be open.
    3. EU Horizon Europe: Similar open-access mandate.
    4. India’s challenge: At a time when the world moves toward open access, ONOS risks becoming an expensive detour.

    Structural Flaws in Scholarly Publishing

    1. Dependence on foreign publishers: ONOS continues India’s reliance on Western journals.
    2. Copyright transfer: Indian researchers must still give away rights to their work.
    3. Pay-to-publish dilemma: Funds freed at institutions may shift to open-access journals, but may ignore institutional repositories.
    4. Need for rights retention: Policies like Harvard/MIT (mandatory deposit in repositories) could empower Indian researchers.

    Conclusion

    The Sci-Hub ban highlights the persistent inequities in access to scientific knowledge. While ONOS is a step forward, it risks being a band-aid solution unless paired with deeper reforms: indigenous publishing capacity, national repositories, and copyright retention policies. India must not merely manage the symptoms of an exploitative system but must cure the disease by reclaiming knowledge as a public good.

    Value Addition

    Knowledge as a Public Good

    • Publicly funded research must be accessible to all because it is financed by taxpayers.
    • Blocking access (through high subscription fees or court orders) creates an elitist knowledge economy.
    • UN and UNESCO treat knowledge access as a pillar of Sustainable Development Goals (SDG 4: Quality Education, SDG 9: Innovation).

    Economic Dimension

    • Global publishers enjoy 30%+ profit margins, while Indian institutions pay lakhs per journal subscription, draining public funds.
    • ONOS at ₹6,000 crore (2023–2026) represents bulk negotiation power by the state, saving scattered institutional expenditure.
    • Issue of dependency on foreign publishers persists, highlighting the need for indigenous publishing ecosystems.

    Global Comparisons

    • U.S. (2026 mandate): All federally funded research must be openly accessible.
    • EU’s Horizon Europe: Immediate open access to publications funded under the programme.
    • Plan S (Europe, 2018): Publicly funded research must be published in open-access journals.
    • India risks being out of sync if it over-invests in subscriptions while others move to free access models.

    Technology and Governance

    • ONOS = India’s experiment in e-governance for knowledge.
    • Needs to integrate institutional repositories, preprint servers, and rights retention policies (like Harvard/MIT) to empower researchers.
    • Can be linked with the Digital India mission, showing tech-driven democratization of services.

    Ethical Dimension

    • Applied Ethics of Technology: Corporate profits vs. collective social welfare.
    • Moral dilemma: Should intellectual property rights override public access to life-saving or path-breaking research?
    • Covid-19 demonstrated that open-access collaboration saved lives by accelerating vaccine and drug development.

    PYQ Relevance

    [UPSC 2024] ‘’What is the present world scenario of Intellectual Property Rights? Although India is second in the world to file patents, still only a few have been commercialized. Explain the reasons behind this less commercialization.”

    Linkage: The Sci-Hub ban and ONOS scheme reflect how IPR in scientific publishing creates barriers to access despite research being publicly funded. Globally, publishers extract high profits through restrictive copyright, mirroring the broader challenge of IPR becoming a tool of rent-seeking rather than innovation. India’s weak indigenous publishing ecosystem and overdependence on foreign journals parallel the problem of low commercialization of patents—both highlight the gap between innovation output and practical accessibility/utility.

  • SpaceX’s Starship completes critical test flight

    Why in the News?

    SpaceX’s Starship has completed its first fully successful test flight after a series of failures.

    SpaceX’s Starship completes critical test flight

    About SpaceX Starship:

    • Design: A two-stage heavy-lift launch vehicle built to carry crew and cargo to Earth orbit, the Moon, Mars, and beyond.
    • Developer: SpaceX, founded by Elon Musk, with the vision of enabling interplanetary travel and colonisation.
    • Size: Nearly 120 metres tall with booster, making it the largest rocket ever built and flown. Taller than Saturn V (111 m) and India’s Qutub Minar (72.5 m).
    • Historic Test Flight: On 27 August 2025, achieved its first fully successful flight. Booster splashed down in the Gulf of Mexico, spacecraft reached the Indian Ocean.
    • Role in NASA Missions: Critical to Artemis Program for returning humans to the Moon and later missions to Mars.
    • Long-term Goal: Make Starship fully and rapidly reusable, cutting costs and redefining space travel.

    Key Features of Starship:

    • Two-Stage Rocket System:
      • Super Heavy booster powered by 33 Raptor engines generating 74 meganewtons of thrust, nearly double NASA’s SLS and twice Saturn V.
      • Engines burn liquid oxygen and methane, enabling deep-space use and Mars resource utilisation.
      • Booster fully reusable, capable of atmospheric re-entry and recovery.
      • Six Raptor engines and four landing fins, designed for full reusability on long-duration missions.
    • Payload Capacity: Can carry up to 150 tonnes to Low-Earth Orbit and over 100 tonnes to the Moon and Mars, more than all soft-landed lunar payloads combined.
    • Cost Reduction Potential: Estimated to deliver 100 tonnes of cargo to Mars for ~$50 million, compared to NASA Shuttle’s $1.5 billion per launch with far less payload.
    [UPSC 2025] Consider the following space missions:

    I. Axiom-4 II. SpaDeX III. Gaganyaan

    How many of the space missions given above encourage and support microgravity research?

    Options: (a) Only one (b) Only two (c) All the three* (d) None

     

  • [pib] India hosts 3GPP RAN Working Group Meetings on 6G Standardization

    Why in the News?

    The Telecommunications Standards Development Society (TSDI) of India has hosted the 3GPP Radio Access Networks (RAN1–RAN5) Working Group Meetings focusing on 6G standardization for the first time, in Bengaluru.

    About 3GPP (3rd Generation Partnership Project):

    • Overview: Global body established in 1998 for mobile telecom standards (2G → 6G).
    • Partners: Collaboration of ARIB (Japan), ATIS (USA), CCSA (China), ETSI (Europe), TSDSI (India), TTA (South Korea), and TTC (Japan).
    • Output: Publishes technical specifications, forming the global benchmark for telecom operators, equipment makers, and regulators.
    • Focus Areas:
      1. RAN (Radio Access Network) – towers & radios connecting users to the network.
      2. Core Network – switching, routing, internet connectivity.
      3. Services & System Aspects – apps, charging, security.

    What is RAN (Radio Access Network)?

    • Definition: The wireless part of a mobile network that links user devices (phones, IoT) to the core network using radio waves.
    • Components:
      • Base Stations (Node B in 3G, eNodeB in 4G, gNodeB in 5G).
      • Antennas & radios.
      • Controllers (e.g., RNC in 3G).
    • Functions:
      • Transmits & receives radio signals.
      • Allocates spectrum.
      • Manages coverage, speed, call/data quality, and handovers.
    • Importance: Defines network performance (speed, latency, capacity).
    • 3GPP RAN Working Groups (RAN1–RAN5): Develop physical layer, radio protocols, performance testing, ensuring smooth migration from 4G → 5G → 6G.

    Back2Basics:  Evolution of Mobile Standards

    • 3G (UMTS – Universal Mobile Telecommunications System): Introduced in early 2000s; based on WCDMA; enabled video calls, MMS, and mobile internet (up to 2 Mbps).
    • 4G (LTE – Long-Term Evolution): All-IP, OFDMA-based; provided high-speed broadband (hundreds of Mbps), VoLTE, and seamless video streaming.
    • 5G (NR – New Radio): Flexible OFDM-based; delivers ultra-high speeds (Gbps), ultra-low latency, supports IoT, automation, AR/VR, and network slicing.
    • 6G (Sixth Generation – under research): Expected by ~2030; aims for terabit-class speeds, AI-native networking, holographic communication, and satellite–terrestrial integration.

     

    [UPSC 2019] With reference to communication technologies, what is/are the difference / differences between LTE (Long-Term Evolution) and VoLTE (Voice over Long-Term Evolution)?

    1. LTE ‘is commonly marketed as 3G and VoLTE is commonly marketed as advanced 3G.

    2. LTE is data-only technology and VoLTE is voice-only technology.

    Select the correct answer using the code given below.

    Options: (a) 1 only (b) 2 only (c) Both 1 and 2 (d) Neither 1 nor 2*

     

  • Discovery of Rare Quadruple Star System with Brown Dwarfs

    Why in the News?

    Scientists have identified UPM J1040−3551 AabBab, a rare quadruple star system with two brown dwarfs orbiting two red dwarfs.

    Discovery of Rare Quadruple Star System with Brown Dwarfs

    About UPM J1040−3551 AabBab:

    • Overview: Newly discovered quadruple star system in the Milky Way.
    • Composition: Two cold T-type brown dwarfs orbiting a pair of young red dwarf stars.
    • Uniqueness: First known system of its kind; extremely rare as brown dwarfs usually exist alone, with less than 5% chance of companions.
    • Significance: Offers new insights into the formation and evolution of low-mass stars and sub-stellar objects.

    What are Brown Dwarfs?

    • Overview: Celestial objects between stars and planets in characteristics.
    • Formation: Form like stars from collapsing gas and dust but lack sufficient mass for sustained hydrogen fusion.
    • Nickname: Often called “failed stars” due to absence of sustained nuclear fusion.
    • Mass Range: Can reach up to about 70 times the mass of Jupiter.
    • Atmosphere: Similar to gas giants like Jupiter and Saturn, with molecules and water vapor clouds.
    • Detection: Very faint and cold; usually identified in multiple-star systems where brighter stars help estimate their properties.
    • Astronomical Importance: Help define the boundary between stars and planets; provide clues to conditions necessary for stellar and planetary formation.
    • Cosmological Role: Studying their abundance and distribution aids in understanding mass distribution in the universe and connections to dark matter.
    [UPSC 2024] Consider the following statements:

    Statement-I: Giant stars live much longer than dwarf stars.

    Statement-II: Compared to dwarf stars, giant stars have a greater rate of nuclear reactions.

    Which one of the following is correct in respect of the above statements?

    Options: (a) Both Statement-I and Statement-II are correct and Statement-II explains Statement-I

    (b) Both Statement-I and Statement-II are correct, but Statement-II does not explain Statement-I

    (c) Statement-I is correct, but Statement-II is incorrect

    (d) Statement-I is incorrect, but Statement-II is correct*

     

  • First Human Case of New World Screwworm in US

    Why in the News?

    The US authorities have reported the first human case of the flesh-eating parasite, the New World screwworm.

    About New World Screwworm (Cochliomyia hominivorax):

    • Overview: Called “man-eater” larvae in Latin; South America and the Caribbean.
    • Larval Stage: Eggs hatch into maggots that burrow into wounds of warm-blooded animals (including humans) and feed on living flesh in a screw-like motion.
    • Life Cycle: After feeding, larvae fall to soil, pupate, and emerge as adult Blue-grey blowfly.
    • Human Infestation (Myiasis): Causes painful non-healing wounds, bleeding, foul odour, sensation of movement; may lead to sepsis or death if untreated.
    • Eradication in USA: Eliminated in 1966 using Sterile Insect Technique (SIT) by mass release of sterile males.

    Current Spread and Concerns:

    • Recent Outbreaks: Detected in Panama, Costa Rica, Nicaragua, and Honduras.
    • Cause of Spread: Likely linked to movement of infested cattle across regions.
    • Possible Weakness in SIT: Current strain of sterilized flies may be less effective than earlier strains.
    • New Human Case: First travel-associated screwworm myiasis reported in the United States in 2025.
    • Livestock Threat: Serious danger to cattle industry; risk of animal suffering and economic loss.
    • Biosecurity Risk: Reemergence could undo decades of eradication efforts if uncontrolled.
    [UPSC 2017] Consider the following statements:

    1. In tropical regions, Zika virus disease is transmitted by the same mosquito that transmits dengue.

    2. Sexual transmission of Zika virus disease is possible.

    Which of the statements given above is/are correct?

    Options: (a) 1 only (b) 2 only (c) Both 1 and 2* (d) Neither 1 nor 2

     

  • Asgard Archaea and the Evolution of Complex Cells

    Why in the News?

    Recent research by IISc on Asgard archaea — the closest living relatives of eukaryotes — has shed new light on how simple prokaryotic cells evolved into complex eukaryotic cells with nuclei, cytoskeletons, and organelles.

    About Asgard Archaea:

    • Nature: Tiny microbes living in deep-sea mud and extreme environments.
    • Evolutionary Link: Closest relatives of eukaryotic cells (plants, animals, humans).
    • Importance: Help explain how simple prokaryotic cells (bacteria/archaea) evolved into complex eukaryotic cells.
    • Significance: Considered the “missing link” in the origin of complex life.

    Findings from Indian Institute of Science (IISc) Study:

    • Focus: Scientists studied a subgroup called Odinarchaeota.
    • Discovery: Found two FtsZ genes (most microbes have one) and a tubulin-like gene.
      • FtsZ1: Works like bacterial proteins → forms straight filaments and attaches to cell membranes.
      • FtsZ2: Builds spiral structures but needs helper proteins to stick to membranes.
    • Division of Labour: Cooperation of FtsZ1 and FtsZ2 shows early signs of cellular specialisation.
    • Clue for Evolution: Suggests Asgard microbes were already experimenting with primitive “cytoskeleton” systems, paving way for complex cells.
    [UPSC 2012] Which one of the following sets of elements was primarily responsible for the origin of life on the Earth?

    Options:

    (a) Hydrogen, Oxygen, Sodium

    (b) Carbon, Hydrogen, Nitrogen*

    (c) Oxygen, Calcium, Phosphorus

    (d) Carbon, Hydrogen, Potassium