Daily Prelims Notes 3 July 2022
- July 3, 2022
- Posted by: OptimizeIAS Team
- Category: DPN
Daily Prelims Notes
3 July 2022
Table Of Contents
- Transgender hormone therapy
- New pathway to regulate nitrate absorption in plants
- Oceans Great Dying 2.0: Mass extinction haunts oceans
- Smoke In Cabin, SpiceJet Pilot Declares May Day, Makes Emergency Landing
- Ocean emergency
Subject : Science and Technology
- Transgender status grounds Adam Harry’s dream to be a pilot.
- Private-pilot licence holder working as a delivery person; DGCA says cross sex hormone therapy renders him unﬁt to ﬂy; activist says there is no scientific basis for it.
Transgender hormone therapy
- Transgender hormone therapy, also called hormone replacement therapy (HRT) or gender-affirming hormone therapy (GAHT), is a form of hormone therapy in which sex hormones and other hormonal medications are administered to transgender or gender nonconforming individuals for the purpose of more closely aligning their secondary sexual characteristics with their gender identity.
- This form of hormone therapy is given as one of two types, based on whether the goal of treatment is masculinization or feminization:
- Masculinizing hormone therapy – for transgender men or transmasculine people; consists of androgens and anti estrogens.
- Feminizing hormone therapy – for transgender women or transfeminine people; consists of estrogens and anti androgens.
Reasons given by DGCA to declare unfit to fly:
- Following an extensive evaluation, which included a psychometric test that’s not normally required, the DGCA declared him “temporary unfit” on the grounds of gender dysphoria (unease due to mismatch between sex assigned at birth and a person’s gender identity),
- And because he is undergoing “cross sex hormone therapy”.
- He was advised to complete his treatment and undertake a medical review.
- Since his masculinising hormone therapy is a life-long treatment, the DGCA’s current stand forbids him from ever becoming a pilot in India.
Supreme Court on rights of trans gender :
- In India, the landmark Supreme Court judgement in National Legal Services Authority (NALSA) v Union of India recognised that third gender persons were entitled to fundamental rights under the Constitution.
It held that no third gender persons should be subjected to any medical examination which would invade their right to privacy.
Subject : Environment
- Researchers led by those from the National Centre of Biological Sciences, Tata Institute of Fundamental Re- search, Bengaluru (NCBS- TIFR), have found a new pathway that regulates nitrate absorption in plants.
Importance of Nitrogen for plants
- Nitrogen is one of the most important macronutrients needed for the development of plants.
- It Is a part Of chlorophyll, amino acids and nucleic acids, among others.
- It is mostly sourced from the soil where it is mainly absorbed in the form of nitrates and ammonium by the roots.
- Nitrates also play a role in controlling genome-wide gene expression that in turn regulates root system architecture, flowering time, leaf development, etc.
- Thus, while a lot of action takes place in the roots to ab- sorb and convert nitrogen into useful nitrates, the absorbed nitrates in turn regulate plant development apart from being useful as a macronutrient.
Nitrate overuse and it’s impact:
- The presence of nitrates is important for the plant development and also for grain production.
- However, the overuse of nitrates in fertilizers, for instance, can lead to the dumping of nitrates in the soil which leads to accumulation of nitrates in water and soil. This accumulation adds to soil and water pollution and increased contribution to greenhouse gases.
- To avoid this, there should be optimal use of nitrates. Also, since the whole process of nitrate absorption takes place in the roots, a well-developed root system is needed for this to take place optimally.
- At one level, it is known that the hormone auxin is responsible for well-developed roots across all plants.
- A number of genes are known to help with auxin production, improved nitrate transport and assimilation in plants.
Regulatory switches: Alternative Pathway to regulate nitrate absorption
- The gene MADS27, which regulates nitrate absorption, root development and stress tolerance, is activated by the micro-RNA, miR444, therefore offers a way to control these properties of the plant.
- The researchers studied this mechanism in both rice (monocot) and tobacco (dicot) plants.
Subject : Environment
- Scientists warn an imminent mass annihilation of marine species similar to one 250 million years ago that wiped out most lives in oceans
- The scientists from Stanford University had simulated during 2016-2018 how Earth’s climate changed some 250 million years ago to know what triggered the Permian extinction.
- The planet’s biggest mass extinction of species had wiped out most newly evolved lives in the oceans.
- It held clues to how the current climate crisis would impact the oceans.
The Permian era
- The Permian era, a period spanning 298.9 million-252.2 million years ago, was a time before the dinosaurs ruled the planet. Global ocean temperatures were 10 degrees higher than today. Oxygen levels were 80 percent lower.
- During this period, land masses collided to form the supercontinent Pangaea. The super continent was arid; only a few parts received rainfall round the year.
- However, the large Panthalassic Ocean, which covered much of Earth, was home to many sponge and coral species, ammonites (tiny shelled organisms), brachiopods (invertebrate animals closely related to starfish) and fusulinid foraminifera (single-celled organisms closely associated with modern amoebas). Reptiles began to flourish. Sharks and bony fishes also thrived.
- Towards the end of the era, a series of volcanic eruptions occurred in central Siberia, injecting massive amounts of greenhouse gases (GHG) into the atmosphere. Then, as now, the uncontrolled GHG emissions triggered climatic changes.
What scientists found in the simulated scenario?
- The change in climate after the volcanic eruptions was a death knell for the flourishing and diverse life forms.
- Many long-lived lineages vanished. Roughly 96 per cent of marine species and 70 per cent of land species went extinct. They then warmed up the climate by 2-10 degrees Celsius to see how species responded.
- Some species will have to leave because it got too hot or the oxygen got too low. Some species from the tropics can move into polar waters because it is more welcoming
- The scientists refer to this period as the ‘Great Dying’
- The scientists had an affirmative answer to their query: Whether low oxygen and warm conditions drove the extinction of marine organisms 250 million years ago.
- This is important because climate change that happened at the end of the Permian era is similar to the one that is unfolding now.
- Deep oceans are warming up.
- Scientists look at ocean heat content as an indicator of climate change. Ocean heat content is the energy accumulated by the ocean.
- Continuous GHG emissions are preventing heat from going back into space. But the atmosphere has a low heat capacity compared to the ocean water, which can accommodate 1000 times more heat. So, most of it is moving into the ocean.
- If emissions continue to climb and temperatures reach around 4.9 degrees Celsius by the end of this century, close to about 40 percent of marine genera could perish by 2300 and 8 per cent by 2100.
Subject : Science and Technology
What is a Mayday call?
- Mayday is a distress call that is used to signal a life-threatening emergency, usually on a ship or a plane, although it may be used in a variety of other situations.
- A typical distress call will start with the word “Mayday” being said three times in a row so that it is not mistaken for another similar-sounding word or phrase.
- This is followed by relaying the information that rescuers would need, including the nature of the emergency, the location or last known location, current weather, type and identity of craft involved, fuel remaining and the number of people in danger. The distress call has absolute priority over all other transmissions.
How did it originate?
The Mayday call originated in the 1920s. A senior radio officer at London’s Croydon Airport in London, Frederick Stanley Mockford, was the first to use this signal to indicate emergency situations. Mockford was asked by his seniors to think of a word that would indicate distress and would easily be understood by all pilots and ground staff during an emergency. As much of the traffic at Croydon airport at that time was to and from Le Bourget Airport in Paris, Mockford proposed the expression “Mayday” derived from the French word “m’aider” that means “help me” and is a shortened form of “venezm’aider”, which means “come and help me”.
What was used earlier?
SOS, short for “save our souls” sent by Morse code, predates the use of Mayday. In 1927, the International Radiotelegraph Convention adopted Mayday as the radiotelephone distress call in place of SOS.
What is the other distress calls used?
One popular emergency call is the Pan-pan, derived from the French word “panne” that means “a breakdown”. It indicates an urgent situation such as a mechanical failure or a medical problem. A Pan-pan call is generally of a notch lower than a Mayday in terms of threat. Pan-pan is the international standard urgency signal that someone aboard a boat, ship, aircraft or other vehicle has an urgent situation, but which, for the time being, does not pose an immediate danger to anyone’s life or to the vessel itself.
What is the format for relaying a Mayday call?
The pilot or ship’s captain must call out “Mayday, Mayday, Mayday” loudly. Following this, the pilot has to read aloud the name of his station, aircraft/ship call sign and type, nature of emergency, weather, pilot’s intentions and/or requests, present position and heading, and if lost then the last known position and heading and time when aircraft was at that position, altitude or flight level, fuel remaining in minutes, the number of people on board, followed by any other useful information.
Section : Climate change
- Ecological service provided by Ocean
- Absorb 90% excess heat generated by GHG
- Produce upto 80% of world’s O2
- Absorb 30% of CO2 emissions
- Climate change impact on Ocean
- 2021 saw record heat absorbed by upper 2000 metres of ocean(epipelagic zone)
- 14% coral lost,30% ocean acidity increase and sea surface temperature
- 50% increase in marine heatwave
- 13% decline in arctic ice cover past decade
- Poleward shift of different marine species
- Most of the ocean species yet to be classified
- Only 20% of sea floors has been explored
- Despite 2021 being la Nina year ocean warming continued
- Deep sea mining will release sediments and other waste from sea floor.
- Ocean basin classification from coast to submarine floor
- Continental shelf, continental slope, continental rise, abyssal plain, trenches
- Special report on the ocean and cryosphere in achanging climate published by IPCC
The open ocean is an enormous place. In fact, more than 99% of the inhabitable space on earth is in the open ocean. In order to better study and understand this huge ecosystem, scientists divide it into different zones:
- The epipelagic zone (or upper open ocean) is the part of the ocean where there is enough sunlight for algae to utilize photosynthesis (the process by which organisms use sunlight to convert carbon dioxide into food). Generally speaking, this zone reaches from the sea surface down to approximately 200 m (650 feet). The epipelagic is home to all sorts of iconic animals, like whales and dolphins, billfishes, tunas, jellyfishes, sharks, and many other groups. Algae that live in the epipelagic zone are responsible for much of the original food production for the entire ocean and create at least 50% of the oxygen in the atmosphere (both through photosynthesis). Organisms that live in the epipelagic zone may come into contact with the sea surface.
- The mesopelagic zone (or middle open ocean) stretches from the bottom of the epipelagic down to the point where sunlight cannot reach. Generally speaking the deep end of the mesopelagic zone is approximately 1000 m (3300 feet) deep. The mesopelagic zone is much larger than the epipelagic, and the most numerous vertebrates on Earth (small bristlemouth fishes) live in this zone. Many of the species of fishes and invertebrates that live here migrate up into shallower, epipelagic depths to feed, but only under the cover of night.
- The next deepest zone is called the bathypelagic zone (or lower open ocean). This zone starts at the bottom of the mesopelagic and stretches down to 4000 m (13,000 feet). The bathypelagic is much larger than the mesopelagic and 15 times the size of the epipelagic. It is the largest ecosystem on earth. The upper bound of this zone is defined by a complete lack of sunlight. Organisms in the bathypelagic live in complete darkness, 24 hours per day. The darkness can be interrupted, however, by some light caused by the organisms themselves. This so called bioluminescence can be used to attract prey or to find a mate. Some species have lost their ability to see anything at all.
- Deeper still is the abyssopelagic zone, which stretches from the bottom of the bathypelagic to the seafloor. This zone is characterized by a relative lack of life. It truly is the abyss.
- A special zone that only exists in certain places around the world is called the hadopelagic zone. Where deep, wide trenches occur in the otherwise flat seafloor, the open water that fills them is the hadopelagic zone. By this definition, all of the deepest parts of the ocean conclude in the hadopelagic. The deepest known ocean depth is nearly 11,000 m (36,000 feet or almost 7 miles).
Finally, organisms that live on the ocean floor (regardless of depth) are part of the benthos. Benthic ecosystems include coral reefs, seagrass beds, and other systems in shallow coastal areas and deep hydrothermal vents, the abyssal plain, and other systems in the deep sea.