Daily Prelims Notes 6 May 2024

Daily Prelims Notes

6 May 2024

1. Can the newly discovered organelle help engineer plants to fix nitrogen?

Sub: Sci

Sec: SciTech

Endosymbiotic Theory:

• Initially posited by Charles Darwin in the 19th century, the theory of natural selection explains how species adapt to their environment.
• Contrary to the Neo-Darwinist focus on random genetic mutations, Lynn Margulis proposed the endosymbiotic theory suggesting that organelles such as mitochondria and chloroplasts (the sites of cellular respiration and photosynthesis) originated from free-living bacteria ingested by other cells. Despite initial resistance and rejection by 15 journals, her theory gained acceptance following publication in 1967.

Recent Discoveries in Nitrogen Fixation:

• Nitrogen, crucial for DNA and proteins, is mostly inert in the atmosphere, necessitating biological fixation into ammonia by certain bacteria and archaea. This process is vital for making nitrogen accessible to plants.
  • Unlike many free-living nitrogen-fixing bacteria, legumes, a class of plants in the family Fabaceae, bear the nitrogen-fixing bacteria in their root nodules.
  • Ammonia is converted to nitrites and nitrates (nitrification) and then back into atmospheric nitrogen (denitrification) with the help of bacteria to complete the cycle.
• In marine environments, like on Earth, bacteria and archaea are also involved in ammonification, nitrification, and denitrification. Beyond mitochondria and chloroplasts, the current discovery extends the earlier reports of a nitrogen-fixing cyanobacterium in marine algae and establishes it as a new organelle. The new organelle ‘nitroplast’ co-evolved with its host cell.
  • Jonathan Zehr and Kyoko Hagino’s research established the symbiotic relationship between the marine algae Braarudosphaera bigelowii and the cyanobacterium Candidatus Atelocyanobacterium thalassa or UCYN-A (capable of fixing nitrogen).
• Unlike mitochondria and chloroplast endosymbiosis, which happened nearly two billion years back, nitroplast’s evolution as an organelle is relatively recent (about 100 million years).

Criteria for Organelle Status:

• Nitroplast satisfies essential criteria for being considered an organelle, such as integration into the host cell’s function and architecture, protein import from the host, synchronization with host cell growth, and inheritance during cell division.
• Genomic and Functional Adaptation: The transformation of symbionts into organelles involves significant genetic reduction and reliance on host cell proteins, with nitroplasts exhibiting these characteristics.

Significance of the discovery:

• The industrial synthesis of ammonia via the Haber-Bosch process has significantly boosted agriculture but also led to environmental issues. The discovery of nitroplasts may lead to sustainable agricultural practices by facilitating biological nitrogen fixation in plants.
• Potential applications include engineering host cells and nitroplasts with minimal genomes for efficient growth and nitrogen fixation, and introducing nitroplasts into plant cells to directly fix nitrogen. These approaches, while promising, pose significant scientific challenges and are currently theoretical.
• The extension of the endosymbiotic theory to include nitrogen-fixing organelles represents a significant leap in understanding cellular evolution and symbiosis. This advancement not only deepens our comprehension of biological complexity but also holds transformative potential for agriculture, promising a future of environmentally friendly and sustainable farming practices.

Source: TH

2. Denotifying Pulicat  Bird Sanctuary

Subject: Environment

Sec: Protected Areas

Context:

• The Pulicat Lake, located across Andhra Pradesh and Tamil Nadu, faces a significant threat from industrial expansion.

Details:

• The Tamil Nadu government has initiated processes to denotify parts of the Pulicat bird sanctuary, which is a critical habitat for diverse aquatic and avian species.
  • The sanctuary was notified in 1980 under Section 18 of the Wild Life (Protection) Act, of 1972.
• Recent moves to settle local claims and the potential reduction of the eco-sensitive zone around the sanctuary have alarmed environmentalists.
• The discharge from surrounding industries has already damaged the lake’s aquatic life, exacerbated by the introduction of invasive species like charru mussels, which further threaten local marine populations.
• The current re-notification under the Wild Life (Protection) Act, 1972, has nothing to do with the demarcation of the ESZ, which is to be done under the Environment (Protection) Act, 1986.

Pulicat lake:

• India’s second-largest brackish water lagoon.
• Located across Andhra Pradesh (96%) and Tamil Nadu (3%).
• The lagoon is one of three important wetlands that attracts northeast monsoon rain clouds during the October to December season.
• The lagoon comprises the following regions: Pulicat Lake (Andhra Pradesh and Tamil Nadu), Marshy/Wetland Land Region (AP), Venadu Reserve Forest (AP), and Pernadu Reserve Forest (AP).
• The barrier island of Sriharikota separates the lagoon from the Bay of Bengal.
•  Arani River and the Kalangi River feed the lagoon.
• The Buckingham Canal, a navigation channel, is part of the lagoon on its western side.

Eco-Sensitive Zones (ESZ):

• The National Wildlife Action Plan (2002-2016) of the Ministry of Environment, Forest and Climate Change (MoEFCC) stipulated that state governments should declare land falling within 10 km of the boundaries of national parks and wildlife sanctuaries as eco-fragile zones or Eco-Sensitive Zones (ESZs) under the Environmental (Protection) Act, 1986.
• While the 10-km rule is implemented as a general principle, the extent of its application can vary. Areas beyond 10 km can also be notified by the Union government as ESZs if they hold larger ecologically important “sensitive corridors”.

Activities in ESZs:

• Prohibited Activities: Commercial mining, sawmills, industries causing pollution (air, water, soil, noise etc), establishment of major hydroelectric projects (HEP), commercial use of wood.
• Regulated Activities: Felling of trees, the establishment of hotels and resorts, commercial use of natural water, erection of electrical cables, drastic change of agriculture system, e.g., adoption of heavy technology, pesticides etc, widening of roads.
• Permitted Activities: Ongoing agricultural or horticultural practices, rainwater harvesting, organic farming, use of renewable energy sources, and adoption of green technology for all activities.

Significance of ESZs:

• To minimise the impact of urbanisation and other developmental activities, the areas adjacent to protected areas have been declared as Eco-Sensitive Zones.
• ESZs help in in-situ conservation, which deals with the conservation of an endangered species in its natural habitat, for example, the conservation of the One-horned Rhino of Kaziranga National Park, Assam.
• ESZs minimise forest depletion and man-animal conflict.
• The protected areas are based on the core and buffer model of management, through which local area communities are also protected and benefitted.
• The purpose of declaring eco-sensitive zones around protected areas is to create some kind of a ‘Shock Absorber’ for the protected area.
• They also act as a transition zone from areas of high protection to areas involving lesser protection.

Source: TH

3. Covid virus is still here. Why aren’t more people falling ill?

Subject: Science and tech

Sec: Health

Context:

• There were 850 active cases as of Friday, according to the Health Ministry.

More on news:

• In the first three weeks of that month, more than 3 lakh positive cases were detected every day on average.
• Daily detections peaked exactly three years ago on May 6, 2021 when more than 4.14 lakh positive cases were reported.

Is the pandemic finally over?

• On May 5, 2023, the World Health Organisation (WHO) announced that Covid-19 was no longer a global public health emergency.
• India had withdrawn all Covid-19-related restrictions after March 31, 2022, shortly after the Omicron wave had dissipated and ceased the application of the provisions of the Disaster Management Act.

Why aren’t more people getting infected?

• The Omicron variant, which emerged at the end of 2021, had enhanced capability to spread and infect people, but it did not cause severe disease.
• A large proportion of the world’s population gained natural immunity after being infected with Omicron.
• The decline in the number of people without immunity, either through natural infection or vaccination, meant that the virus had fewer opportunities to evolve rapidly into newer variants.
• However, neither natural infection nor vaccines provide permanent immunity.
• The effect of vaccines taken in 2021 and 2022 is most likely over.
• Natural immunity also dissipates after some time.
• The only reason there is no uncontrolled surge is that people are continuing to get infected with relatively harmless variants, and getting their immunity renewed.

About Covid 19 and its strains:

• Coronaviruses are a specific family of viruses, with some of them causing less-severe damage, such as the common cold and others causing respiratory and intestinal diseases.
• These are enveloped RNA viruses that cause respiratory illnesses of varying severity from the common cold to fatal pneumonia. 
• The dominant variant causing the most infections right now is JN.1, a distant descendant of Omicron. JN.1 is a little more efficient at infecting people than its sister variants  but like all descendants of Omicron, does not cause severe disease.
• The presence of Beta variant was first reported from India during December 2020.
• Various SARS- CoV-2 variants i.e., Alpha, B. 1.1. 28.2, Eta, Kappa, Delta, Delta AY have been detected from India.
• The Delta variant first detected in India remains the most worrisome.
  • It has proven capable of infecting a higher proportion of vaccinated people than its predecessors.
  • The WHO classifies Delta as a variant of concern, meaning it has been shown capable of increasing transmissibility, causing more severe disease or reducing the benefit of vaccines and treatments.
• The Lambda variant has attracted attention as a potential new threat.

Types of Immunities:

• Active Immunity results when exposure to a disease organism triggers the immune system to produce antibodies to that disease.
  • Natural immunity happens after you get infected by a germ and your immune system responds by making antibodies to it.
• Passive immunity is provided when a person is given antibodies to a disease rather than producing them through his or her own immune system.
  • A newborn baby acquired passive immunity from its mother through the placenta.

4. What is Artificial General Intelligence (AGI), and why are people worried about it?

Sub: Sci

Sec: Awareness of computer and AI

Context:

• In a recent interview, Sam Altman, CEO of OpenAI, expressed his commitment to invest billions of dollars towards the development of Artificial General Intelligence (AGI).

What is AGI?

• AGI refers to a machine or a software that can perform any intellectual task that a human can do. 
• This includes reasoning, common sense, abstract thinking, background knowledge, transfer learning, ability to differentiate between cause and effect, etc.
• AGI aims to emulate human cognitive abilities such that it allows it to do unfamiliar tasks, learn from new experiences, and apply its knowledge in new ways.

How is AGI different from AI we already use?

• The main difference between AGI and the more common form of AI, also known as narrow AI, lies in their scope and capabilities.
• Narrow AI is designed to perform specific tasks such as image recognition, translation, or even playing games like chess—at which it can outdo humans, but it remains limited to its set parameters.
• On the other hand, AGI envisions a broader, more generalized form of intelligence, not confined to any particular task (like humans).

Idea of AGI?

• The idea of AGI first emerged in the 20th century with a paper written by Alan Turing, widely considered to be the father of theoretical computer science and artificial intelligence.
• In ‘Computing Machinery and Intelligence’ (1950), he introduced what is now known as the Turing test, a benchmark for machine intelligence.

How can AGI help humanity?

• AGI has innumerable positive implications.
• For instance, in healthcare, it can redefine diagnostics, treatment planning, and personalized medicine by integrating and analyzing vast datasets, far beyond the capabilities of humans.
• AGI could automate various processes and enhance the overall decision-making, offering real-time analytics and market predictions with accuracy.

5. Swell waves hit coastal Kerala

Sub: Geo

Sec: Oceanography

Context: Tension gripped the residents of coastal areas in Kerala on Saturday night after high swell waves pounded the coast

What are Swell Waves?

• These waves are formed by an ocean swell; hence the name swell surge.
• Ocean swells occur not due to the local winds, but rather due to distant storms like hurricanes or even long periods of fierce gale winds.
• During such storms, huge energy transfer takes place from the air into the water, leading to the formation of very high waves. Such waves can travel thousands of kilometres from the storm centre until they strike shore.

What is the Difference Between Swell Waves and Tsunamis?

• Unlike swell waves, a tsunami is a series of enormous waves created by an underwater disturbance usually associated with earthquakes occurring below or near the ocean.
• Tsunamis are around 10 times faster than swell waves. Although both swell waves and tsunamis slow down near the coast, the latter hit land at 30–50 km/h.

Which are the Most Vulnerable Regions in India?

• Usually, states like Kerala witness swell waves as a result of strong winds in the southern part of the Indian Ocean.
• The March swell waves were generated after a low atmospheric pressure system moved over the region from the South Atlantic Ocean — 10,000 kilometres off the Indian coast. The arrival of the pressure system resulted in strong winds, which led to the formation of swell waves of up to 11 metres in height. These waves hit the Kerala coast and Lakshadweep.
• In March 2024, swell waves led to flooding in several areas of Kerala – the worst affected were Alappuzha, Kollam, and Thiruvananthapuram districts.
• Such flooding events are called Kallakkadal in Kerala.

Forecasting:

• To forecast swell waves, INCOIS launched the Swell Surge Forecast System in 2020 which can give      warning seven days in advance.