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1905 In Science
The year 1905 in science and technology involved some significant events, particularly in physics, listed below. Astronomy * January 2 – Charles Dillon Perrine at Lick Observatory discovers Elara, one of Jupiter's natural satellites. * The Dominion Observatory opens in Ottawa. * Various astronomers discover the minor planets 554 Peraga through 583 Klotilde (''see'' List of minor planets/501–600). * The nova V604 Aquilae appears in the constellation Aquila. * The Umov effect is noted by Nikolay Umov. Biology * April 18 – William Bateson coins the term "genetics" in a letter to Adam Sedgwick. * Reginald Punnett's ''Mendelism'' is published in Cambridge (U.K.), probably the first popular science book on genetics. * Frederick Blackman proposes his law of limiting factors in relation to photosynthesis. * Nettie Stevens and Edmund Beecher Wilson independently describe the XY sex-determination system. * Stamen Grigorov identifies the bacterium ''Lactobacillus bulgaricus'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Science
Science is a systematic endeavor that builds and organizes knowledge in the form of testable explanations and predictions about the universe. Science may be as old as the human species, and some of the earliest archeological evidence for scientific reasoning is tens of thousands of years old. The earliest written records in the history of science come from Ancient Egypt and Mesopotamia in around 3000 to 1200 BCE. Their contributions to mathematics, astronomy, and medicine entered and shaped Greek natural philosophy of classical antiquity, whereby formal attempts were made to provide explanations of events in the physical world based on natural causes. After the fall of the Western Roman Empire, knowledge of Greek conceptions of the world deteriorated in Western Europe during the early centuries (400 to 1000 CE) of the Middle Ages, but was preserved in the Muslim world during the Islamic Golden Age and later by the efforts of Byzantine Greek scholars who brought Greek ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Umov Effect
The Umov effect, also known as Umov's law, is a relationship between the albedo of an astronomical object, and the degree of polarization of light reflecting off it. The effect was discovered by the Russian physicist Nikolay Umov in 1905, and can be observed for celestial objects such as the surface of the Moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ... and the asteroids. The ''degree of linear polarization'' of light ''P'' is defined by : P = \frac\ , where I_\perp and I_\, are the intensities of light in the directions perpendicular and parallel to the plane of a polarizer aligned in the plane of reflection. Values of ''P'' are zero for unpolarized light, and ±1 for linearly polarized light. Umov's law states :P \propto \frac\ , where α is the albedo of the object. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacterium
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria are vital in many stages of the nutrient cycle by recycling nutrients such as the fixation of nitrogen from the atmosphere. The nutrient cycle includes the decomposition of dead bodies; bacteria are responsible for the putrefaction stage in this process. In the biological communities surrounding hydrothermal vents and cold seeps, extremophile bacteria provide the nutrients needed to sustain life by converting dissolved compounds, such as hydrogen sulphide and methane, to energy. Bacteria also live in symbiotic and parasitic relationshi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stamen Grigorov
Stamen Gigov Grigorov ( bg, Стамен Гигов Григоров; 27 October 1878 – 27 October 1945) was a prominent Bulgarian physician and microbiologist. He discovered the ''Lactobacillus bulgaricus'' bacillus, used in the making of yogurt. Life Stamen Grigorov was born in the village of (lit. "Cold Spring"), , Pernik Province, Bulgaria. He completed his secondary education in natural sciences in Montpellier, France and medical science in Geneva, Switzerland. In 1905, at the age of 27, Grigorov made the discovery for which he is best known. In the microbiological laboratory of Professor Léon Massol in Geneva, he discovered that a certain strain of bacillus is the basis of yogurt. In recognition the strain was called by the scientific community ''Lactobacillus bulgaricus''. In the 1950s, the state-owned yogurt company patented and promoted a specific blend of bacterial strains to create an "official Bulgarian yoghurt". This blend continues to be exported to yogurt produc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
XY Sex-determination System
The XY sex-determination system is a sex-determination system used to classify many mammals, including humans, some insects (''Drosophila''), some snakes, some fish (guppies), and some plants (''Ginkgo'' tree). In this system, the sex of an individual is determined by a pair of sex chromosomes. Females have two of the same kind of sex chromosome (XX), and are called the homogametic sex. Males have two different kinds of sex chromosomes (XY), and are called the heterogametic sex. In humans, the presence of the Y chromosome is responsible for triggering male development; in the absence of the Y chromosome, the fetus will undergo female development. There are various exceptions, such as individuals with Klinefelter syndrome (who have XXY chromosomes), Swyer syndrome (women with XY chromosomes), and XX male syndrome (men with XX chromosomes), however these exceptions are rare. In most species with XY sex determination, an organism must have at least one X chromosome in order to sur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Edmund Beecher Wilson
Edmund Beecher Wilson (October 19, 1856 – March 3, 1939) was a pioneering American zoologist and geneticist. He wrote one of the most influential textbooks in modern biology, ''The Cell''. Career Wilson was born in Geneva, Illinois, the son of Isaac G. Wilson, a judge, and his wife, Carioline Clark. He graduated from Yale University in 1878. He earned his Ph.D. at Johns Hopkins in 1881. He was a lecturer at Williams College in 1883–84 and at the Massachusetts Institute of Technology in 1884–85. He served as professor of biology at Bryn Mawr College from 1885 to 1891. In 1888, he was elected as a member to the American Philosophical Society. He spent the balance of his career at Columbia University where he was successively adjunct professor of biology (1891–94), professor of invertebrate zoology (1894–1897), and professor of zoology (from 1897). Wilson is credited as America's first cell biologist. In 1898 he used the similarity in embryos to describe phylogene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nettie Stevens
Nettie Maria Stevens (July 7, 1861 – May 4, 1912) was an American geneticist who discovered sex chromosomes. In 1905, soon after the rediscovery of Mendel's paper on genetics in 1900, she observed that male mealworms produced two kinds of sperm, one with a large chromosome and one with a small chromosome. When the sperm with the large chromosome fertilized eggs, they produced female offspring, and when the sperm with the small chromosome fertilized eggs, they produced male offspring. The pair of sex chromosomes that she studied later became known as the X and Y chromosomes. Early life Nettie Maria Stevens was born on July 7, 1861, in Cavendish, Vermont, to Julia (née Adams) and Ephraim Stevens. In 1863, after the death of her mother, her father remarried and the family moved to Westford, Massachusetts.MB Ogilvie, CJ Choquette (1981) "Nettie Maria Stevens (1861–1912): her life and contributions to cytogenetics. ''Proc Amer Phil Soc US'' 125(4):292–311. Her father worked a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Annals Of Botany
''Annals of Botany'' is a monthly peer-reviewed scientific journal publishing experimental, theoretical and applied papers on all aspects of plant biology. The current (2022) Chief Editor is Rowan Sage, replacing John Seymour (Pat) Heslop-Harrison (University of Leicester, UK and the South China Botanical Garden appointed in 2008). The journal is owned and managed by thAnnals of Botany Company a non-profit educational charity registered with the Charity Commission for England and Wales. It is published monthly through Oxford University Press in paper form and online, and is paid for primarily by institutional annual subscriptions. Regular extra issues, published free-of-charge, focus on topical themes. The journal does not levy page charges but authors may choose to pay a standard fee to secure open access status for their papers. According to ''Journal Citation Reports'', in 2019 (published 2020) ''Annals of Botany''’s impact factor was 4.005 and was ranked 27th out of 234 jou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photosynthesis
Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's activities. Some of this chemical energy is stored in carbohydrate molecules, such as sugars and starches, which are synthesized from carbon dioxide and water – hence the name ''photosynthesis'', from the Greek ''phōs'' (), "light", and ''synthesis'' (), "putting together". Most plants, algae, and cyanobacteria perform photosynthesis; such organisms are called photoautotrophs. Photosynthesis is largely responsible for producing and maintaining the oxygen content of the Earth's atmosphere, and supplies most of the energy necessary for life on Earth. Although photosynthesis is performed differently by different species, the process always begins when energy from light is absorbed by proteins called reaction centers that contain green chlorophyll (and other colored) pigments/chromoph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frederick Blackman
Frederick Frost Blackman FRS (25 July 1866 – 30 January 1947) was a British plant physiologist. Frederick Blackman was born in Lambeth, London to a doctor. He studied medicine at St. Bartholomew's Hospital, graduating MA. In the subsequent years, he studied natural sciences at the University of Cambridge and was awarded DSc. He conducted research on plant physiology, in particular photosynthesis, in Cambridge until his retirement in 1936. Gabrielle Matthaei was his assistant until 1905. He was elected in May 1906 a Fellow of the Royal Society, his candidature citation reading "Fellow of St John's College, Cambridge. Ex-Lecturer and now Reader in Botany in the University." He has made distinguished investigations in plant physiology. In 1921 he was awarded the Royal Medal and in 1923 delivered the Croonian lecture. He was buried at the Parish of the Ascension Burial Ground in Cambridge, with his wife Elsie (1882 - 1967). Blackman's law of limiting factors Blackman propose ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Popular Science
''Popular Science'' (also known as ''PopSci'') is an American digital magazine carrying popular science content, which refers to articles for the general reader on science and technology subjects. ''Popular Science'' has won over 58 awards, including the American Society of Magazine Editors awards for its journalistic excellence in 2003 (for General Excellence), 2004 (for Best Magazine Section), and 2019 (for Single-Topic Issue). With roots beginning in 1872, ''Popular Science'' has been translated into over 30 languages and is distributed to at least 45 countries. Early history ''The Popular Science Monthly'', as the publication was originally called, was founded in May 1872 by Edward L. Youmans to disseminate scientific knowledge to the educated layman. Youmans had previously worked as an editor for the weekly ''Appleton's Journal'' and persuaded them to publish his new journal. Early issues were mostly reprints of English periodicals. The journal became an outlet for writings ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reginald Punnett
Reginald Crundall Punnett FRS (; 20 June 1875 – 3 January 1967) was a British geneticist who co-founded, with William Bateson, the ''Journal of Genetics'' in 1910. Punnett is probably best remembered today as the creator of the Punnett square, a tool still used by biologists to predict the probability of possible genotypes of offspring. His ''Mendelism'' (1905) is sometimes said to have been the first textbook on genetics; it was probably the first popular science book to introduce genetics to the public. Life and work Reginald Punnett was born in 1875 in the town of Tonbridge in Kent, England. While recovering from a childhood bout of appendicitis, Punnett became acquainted with Jardine's Naturalist's Library and developed an interest in natural history. Punnett was educated at Clifton College. Attending Gonville and Caius College, Cambridge, Punnett earned a bachelor's degree in zoology in 1898 and a master's degree in 1901. Between these degrees he worked as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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