Science Horizon
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Science Horizon Volume 3 Issue 9 September, 2018 President, Odisha Bigyan Academy Editorial Board Prof. Sanghamitra Mohanty Prof. Rama Shankar Rath Chief Editor Er. Mayadhar Swain Prof. Niranjan Barik Prof. G. B. N. Chainy Editor Dr. Trinath Moharana Prof. Tarani Charan Kara Prof. Madhumita Das Managing Editor Prof. Bijay Kumar Parida Dr. Prafulla Kumar Bhanja Secretary, Odisha Bigyan Academy Dr. Shaileswar Nanda CONTENTS Subject Author Page 1. Editorial : Molecular Evolution - An Overview Prof. Tarini Charan Kara 2 2. How Blurred is our belief on a Blood Moon Sri Nikunja Bihari Sahu 4 3. Diamonds in the Night Sky Sri Mohan Kumar Sahu 6 4. Back-of-the-Envelope Calculation : What and How Dr. B. K. Parida 10 Dr. J. K. Mohapatra 5. Fields Medal in Mathematics Er. Mayadhar Swain 14 6. Linus Pauling - The Legend Prof. Suresh Mohapatra 18 7. Environmental Pollution : A Threat To Humanity Dr. Sundara Narayana Patro 21 8. The King of Poisons and the Poison of KingsDr. Choudhury Satyabrata Nanda 28 9. Artificial Intelligence Dr. Dwijesh Kumar Panda 30 10. Rabies - A Fatal Disease Dr. K.K. Sardar 33 Dr. B.C. Das 11. Stem Cell Therapy: a Promise for all Ills ! Dr. Guru Prasad Mohanta 36 12. Aquatic Weeds - Their Control and Uses Dr. Sanjeeb Kumar Das 38 13. Plant Tissue Culture and its Revolution Dr. Gouranga Charan Swain 42 14. Fish : The Global Super Food Sri Biswaranjan Paital 44 15. Quiz : Arsenic Pollution Sri Titaram Nanda Brahmachari, Prof. Surjenu Kumar Dey 47 The Cover Page depicts : Molecular Evolution Cover Design : Sanatan Rout neutron star EDITORIAL MOLECULAR EVOLUTION - AN OVERVIEW In 1958 Charles Darwin and Alfred Russel Darwin (1809-1882) and Mendel (1822- Wallace published a new evolutionary theory, 1884) achieved their insights without any help explained in detail in Darwin's book "The Origin from molecular biological tools and techniques of Species By Means of Natural Selection" (1859). available today. The present day biologists are Unlike Lamarck, Darwin proposed common quite familiar with such tools and techniques descent and a branching tree of life, indicating which help them to go into the molecular that two very different species could share a intricacies of the diverse array of life forms living common ancestor. Though Darwin was not aware on Earth. This facilitated a new field of of genes and DNA, and also not sure about the evolutionary study called - Molecular Evolution origin of variations, yet he described a mechanism which deals with evolution of genes, DNA and of evolution - the theory of natural selection - for proteins at the molecular level. The molecular how evolution shapes life on earth. In the analysis of changes in DNA, Proteins and genome structure throw much light on the dynamics introduction of his book 'The Origin of Species' behind evolutionary processes and allow to Darwin pointed out that, selection is not the only reconstruct the chronology of organic changes and evolutionary force at work, other forces do work construct a Universal tree of life. Molecular in evolution. More or less during the same time approaches are more reliable to establish hardly anyone noticed, when the foundation of evolutionary relationships and to understand how modern genetics was laid down by an Austrian life has evolved over time. monk Gregor John Mendel, whose experiments on the Pea plant was published in the Annual Scientists are learning how the forces of proceedings of the Brno Natural Science Society evolution work on DNA, the biochemical in 1865. repository of an organism's entire natural history. DNA records the mutations that helped some Eventhough, Mendel was aware of a animals to survive the adverse conditions and potential link between his "Units of heredity" and adopt the new environment while others may evolution - he had not made any explicit comment perish. Each organism has its own book of life, on the topic. While discussing the transmission in its genome which is constantly undergoing of hereditary information from generation to editing and revision. Each individual has its own generation, he had discovered the basic laws of edition of its species book, shaped by natural inheritance (genetics). The profound significance selection and other forces of evolution, such as of Mendel's work was not recognized until the genetic mutation, recombination, genetic drift turn of the 20th century. With the rediscovery of and isolation. his laws in 1900 by three different scientists, The studies of molecular evolution has Mendelism got back its lost glory and Mendel provided three kinds of information : Estimation was recognized as the father of modern genetics. of genetic structure of population and species, Then it took nearly half a century before James identification of genes and decoding genome of Watson and Francis Crick (1953) deciphered the different organisms, comparing the genetic structure of DNA, the molecule that contains the records from these genomes to find out how life manual for building an organism. evolved on Earth. It has been mentioned that the mechanism On the basis of nucleotide sequence of for evolution of noble genes and proteins are less 16SrRNA a phylogenetic tree, popularly known understood and the problem is a challenge to the as 'Universal tree of life' have been constructed molecular evolutionary biologists. Nevertheless, by molecular taxonomists in 1997. The root of we accept the fascinating idea that the great this tree of life represents a point where all the diversity of genes in modern organisms are forms of life inhabitating on Earth shared a descendants of a very few ancestral sequences - common origin, called as a Universal Common probably less than a few hundred. But that work Ancestor, or Progenote. The Universal Tree of life is yet to give a conclusive answer and many is well supported by molecular sequencing of questions still remain unanswered. One of the other genes coding for some fundamental proteins biggest unanswered question is whether life on and rRNAs; it reveals the evolutionary differences Earth has been destined to evolve the way it has. of prokaryotes at the level of nucleotide sequence Researchers are still debating the details of how and reveals the separate and independent origin the process(es) of natural selection works together of mitochondria and chloroplasts from eubacterial with other evolutionary forces to shape genes and lineages. Thus molecular approaches are more help organisms adapt to their environments, reliable to establish evolutionary relationships of the three domains of life forms existing on Earth. producing the abundance of species available today. It seems each and every process in the body Earlier, establishing a unified time scale for of living organisms is governed and regulated by the early evolution of Earth and the life is a specific network of genes working together in challenging and mired in controversy because of tune with its environment. paucity of fossil evidence, the difficulty of interpreting fossils and dispute over the deepest Initially, biologists divided all life forms branching relationships in the 'tree of life'. into two primary divisions - the plants and Recently Holly et al. (Aug. 2018) in one of their animals. But this simple dichotomy of the living articles published in the Nature Journal - Ecology world became inadequate. Then organisms were & Evolution, have discussed the derivation of a broadly divided into prokaryotes and eukaryotes time scale of life, using molecular clock analysis on the basis of nucleus. Following this framework, (a technique used in molecular evolution). They a five-kingdom classification was proposed by have reported that the last Universal Common Whittaker (1969). With the introduction of ancestor of cellular life which appeared on Earth molecular sequencing as a tool for finding was more than 3.9 billion years ago. The two relationship among organisms, a new grouping primary divisions of life, Eubacteria and of living world has started and that was not Archaebacteria, emerged much later ( 3.4 billion necessarily based on phenotypic relationship. years ago ). The modern eukaryotes do not Molecular Phylogeny has clearly revealed that constitute a primary lineage of life and emerged Cellular life on earth has evolved along three late in Earth's history, probably less than 1.8 major lineages - Eubacteria, Archea and Eukarya. billion years ago. With these recent findings, it is These three are now termed as domains of life - clear that the use of molecular tools and the highest biological taxon. The two domains techniques would help in the advancements in our are essentially Prokaryotes. Domain Eukarya knowledge and understanding about the origin of includes all eukaryotic kingdoms - Protista, life and to findout the relatedness among the life Plantae, Fungi and Animalia. forms existing on Earth. Prof. Tarani Charan Kara e-mail : [email protected] SEPTEMBER, 2018 HOW BLURRED IS OUR BELIEF ON A BLOOD MOON Sri Nikunja Bihari Sahu The Blood Moons of January 31 and July 27 this year (2018) have aroused much curiosity in the minds of our people. Different people interpreted the events in different ways as our belief on a Blood Moon is generally pass through the atmosphere and get refracted blurred. The imprint of the eclipse is clearly again towards the surface of the fully eclipsed reflected in the altered schedule of our daily Moon illuminating it with a copper red glow. life as it was marked by people indulging in This gives the name Blood Moon. The degree penance, fasting, abstinence from pleasure, of scattered and refracted light depends on the restrictions on the rituals of deities, ban amount of cloud cover and dust particles on embarking distant journeys and many present in the atmosphere. In general, the other such practices during eclipse. dustier the atmosphere, the more likely that However, a Blood Moon is a spectacular the blue wavelengths of light will be celestial event during the totality phase of a eliminated leaving the resulting light a deeper Total Lunar Eclipse when the colour of the red tint.