Essential Facts (Prelims) – May 13 , 2019


Orchid Link

Category: Environment

  • An Assam forest officer’s chance discovery has given India one of its smallest orchids in terms of size and duration of bloom to be recorded botanically.
  • Lecanorchistaiwanianais a mycoheterotroph, one of two types of parasitic plants that have abandoned photosynthesis.
  • Lecanorchistaiwaniana adds to the orchid wealth of northeast India, which has 800 of some 1,300 species in the country.
  • About 300 species are found in the Western Ghats and 200 in the northwestern Himalayas.
  • The orchid, discovered earlier in Japan, Taiwan, and Laos, was found to have a maximum height of 40 cm and a blossoming period of five-six days.
  • As it derives its energy and nutrients from fungus, it may be of herbal importance.

Russian Poplar

Category: Sc& tech

  • In May every year, hospitals and doctors in the Kashmir Valley find themselves treating a high number of patients, especially children, with respiratory diseases. The patients complain of sore throat, cold, cough and fever.
  • While a common cause is pollen shed by various plants, the spike in illness has often been attributed to a phenomenon during this season — the shedding of fluffy cotton-covered seeds by poplar trees, commonly known as “Russian poplars”.
  • Three years ago, this led to the Jammu & Kashmir High Court ordering chopping of all Russian poplars in the Valley.
  • Scientists, on the other hand, have concluded that the seeds from these trees do not cause allergy.
  • “Russian poplar” is a misnomer as the tree has nothing to do with Russia.
  • It was introduced in Kashmir in 1982 under a Word Bank-aided social forestry scheme.
  • The tree is a Western American species known as Eastern Cottonwood (Populusdeltoides) in the US.
  • Over the years, people in the Valley have started to prefer the “Russian poplar” over the native Kashmiri poplar for its quick growth — 10-15 years to reach full size compared to 30-40 years for the Kashmiri poplar.
  • The poplar trees are used to make wooden boxes for transportation of apples and other fruits from the Valley.The high-quality wood is also used in veneer and plywood.
  • With the onset of May, the “Russian poplars” shed their seeds covered in cotton-like material. The cotton-covered seeds can be seen in the air, on the ground and in water-bodies. Around the same time, patients complaining of respiratory diseases swell many times.
  • Health experts stress that the cotton-like material from the poplars is not an allergen. It is the pollen — not visible to the naked eye — shed by “Russian poplars” that causes allergy, and in a relatively small number of people.
  • A study found that the pollen of “Russian poplars” can cause allergic reactions in less than 20% of the population. Compared to this, pollen from common grass is likely to cause allergic reactions in 73.5%, pollen from pine in 62.7% of the population, and pollen from chinar trees in 60% of the population. The study found that the biggest causative agent for respiratory diseases, in fact, is dust that can affect 92.7% of the population.

Manav

Category: Sc& tech

  • The Department of Biotechnology (DBT) has launched ‘MANAV: Human Atlas Initiative’.
  • It is a project for mapping every tissue of the human body to help understand better the roles of tissues and cells linked to various diseases.
  • The programme will seek to provide better biological insights through physiological and molecular mapping, develop disease models through predictive computing, and allow for a holistic analysis and finally drug discovery.
  • The aim of the project is to understand and capture human physiology in two stages — normal stage and disease stage.

Blue Moon

Category: Sc& tech

  • Jeff Bezos has unveiled ‘Blue Moon’, A Lunar Spacecraft to Take Humans to the Moon’s Surface by 2024.
  • Blue Moon is essentially a robotic space cargo carrier that runs on Hydrogen and can make cargo deliveries to the Moon.
  • Built to deliver science payloads, moon rovers and even astronauts to the lunar surface, the spacecraft can also deploy small satellites into lunar orbit as a “bonus mission” on the way.
  • Blue Moon is planned to be capable of delivering 4,500 kg to the surface of the Moon and can also be used as cargo vehicle to support NASA’s outer space activities, or transport payloads of ice from Shackleton Crater, an impact crater that lies at the south pole of the Moon, to support space activities.

Deep Sea Fish

Category: Environment

  • The deep sea is home to fish species that can detect various wavelengths in near-total darkness.
  • The deep sea is the largest habitat on Earth and yet one of the least explored due to its inaccessibility.
  • Many organisms have adapted to life in the near-total darkness of this inhospitable environment. For example, many fish have developed highly sensitive telescope eyes that allow them to detect the tiny amount of residual light that makes it to the depths of the ocean.
  • Fish living in deep-sea habitat and discovered that certain deep-sea fish have expanded their rhodopsin genes.
  • The genes cover exactly the wavelength range of light “produced” by light-emitting organs of deep-sea organisms. This is known as bioluminescence, which is the ability of an organism to produce light on its own or with the help of other organisms.
  • Colour vision is only possible in daylight, however. In the darkness, vertebrates detect the few available light particles with their light-sensitive rod cells, which contain only a single type of the photopigment rhodopsin, explaining why nearly all vertebrates are colour-blind at night

Huntington’s Disease

Category: Sc& tech

  • Huntington’s disease attacks and destroys certain brain cells in human beings.
  • A toxic protein linked to Huntington’s disease can move from neuron to neuron through a nanotube tunnel whose construction is initiated by a protein called Rhes.
  • People with Huntington’s disease inherit a damaged protein that is somehow complicit in destroying brain cells.
  • Huntington’s disease brains are shrunken and degraded. As the neurons deteriorate, people lose motor control, they can have emotional problems and their thinking and memory suffer.
  • Symptoms usually begin around age 30 to 40 and last 15 to 20 years until death. A rarer and more aggressive form of the disease affects children, cutting their childhood and lives short.
  • About three to seven people out of 100,000 have the disease and it has mostly affected those with European ancestry.

Iterative Evolution

Category: Environment

  • A previously extinct species of bird has re-evolved back into existence.
  • The bird, Aldabra, rail first went extinct around 136,000 years ago. Now, it’s reclaimed its home island.
  • Aldabra is an island in Indian ocean.
  • The island has been completely submerged multiple times, wiping out all species inhabiting it.
  • Every time, every species on the island went extinct — but the Aldabra rail has returned, again and again.
  • The rail is an example of iterative evolution — when the same ancestral lineage leads to repeated evolution of a species at different points in time. The rare phenomenon means that species can re-emerge over and over, despite past iterations going extinct.
  • The Aldabra white-throated is a flightless bird — a descendant of a species of flying bird known as the white-throated rail.
  • It was completely wiped out when the island disappeared below sea level about 136,000 years ago.
  • Unlike the famous Dodo of Mauritius, the rails were able to re-emerge from Madagascar once sea levels lowered again.
  • Today, the flightless Aldabra rail has once again reclaimed its island — and it’s now the last surviving species of flightless bird in the Indian Ocean.
  • The study marks the first time iterative evolution has been observed in rails, and represents one of the “most significant” instances ever found in birds.

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