Meselson Effect
Matthew Stanley Meselson (born May 24, 1930) is a geneticist and molecular biologist currently at Harvard University, known for his demonstration, with Franklin Stahl, of semi-conservative DNA replication. After completing his Ph.D. under Linus Pauling at the California Institute of Technology, Meselson became a Professor at Harvard University in 1960, where he has remained, today, as Thomas Dudley Cabot Professor of the Natural Sciences. In the famous Meselson–Stahl experiment of 1958 he and Frank Stahl demonstrated through nitrogen isotope labeling that DNA is replicated semi-conservatively. In addition, Meselson, François Jacob, and Sydney Brenner discovered the existence of messenger RNA in 1961. Meselson has investigated DNA repair in cells and how cells recognize and destroy foreign DNA, and, with Werner Arber, was responsible for the discovery of restriction enzymes. Since 1963 he has been interested in chemical and biological defense and arms control, has served as ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Denver
Denver () is a consolidated city and county, the capital, and most populous city of the U.S. state of Colorado. Its population was 715,522 at the 2020 census, a 19.22% increase since 2010. It is the 19th-most populous city in the United States and the fifth most populous state capital. It is the principal city of the Denver–Aurora–Lakewood, CO Metropolitan Statistical Area and the first city of the Front Range Urban Corridor. Denver is located in the Western United States, in the South Platte River Valley on the western edge of the High Plains just east of the Front Range of the Rocky Mountains. Its downtown district is immediately east of the confluence of Cherry Creek and the South Platte River, approximately east of the foothills of the Rocky Mountains. It is named after James W. Denver, a governor of the Kansas Territory. It is nicknamed the ''Mile High City'' because its official elevation is exactly one mile () above sea level. The 105th meridian we ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Restriction Enzymes
A restriction enzyme, restriction endonuclease, REase, ENase or'' restrictase '' is an enzyme that cleaves DNA into fragments at or near specific recognition sites within molecules known as restriction sites. Restriction enzymes are one class of the broader endonuclease group of enzymes. Restriction enzymes are commonly classified into five types, which differ in their structure and whether they cut their DNA substrate at their recognition site, or if the recognition and cleavage sites are separate from one another. To cut DNA, all restriction enzymes make two incisions, once through each sugar-phosphate backbone (i.e. each strand) of the DNA double helix. These enzymes are found in bacteria and archaea and provide a defense mechanism against invading viruses. Inside a prokaryote, the restriction enzymes selectively cut up ''foreign'' DNA in a process called ''restriction digestion''; meanwhile, host DNA is protected by a modification enzyme (a methyltransferase) that modifi ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Isotope
Isotopes are two or more types of atoms that have the same atomic number (number of protons in their nuclei) and position in the periodic table (and hence belong to the same chemical element), and that differ in nucleon numbers (mass numbers) due to different numbers of neutrons in their nuclei. While all isotopes of a given element have almost the same chemical properties, they have different atomic masses and physical properties. The term isotope is formed from the Greek roots isos ( ἴσος "equal") and topos ( τόπος "place"), meaning "the same place"; thus, the meaning behind the name is that different isotopes of a single element occupy the same position on the periodic table. It was coined by Scottish doctor and writer Margaret Todd in 1913 in a suggestion to the British chemist Frederick Soddy. The number of protons within the atom's nucleus is called its atomic number and is equal to the number of electrons in the neutral (non-ionized) atom. Each atomic numbe ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Frank Stahl
Franklin (Frank) William Stahl (born October 8, 1929) is an American molecular biologist and geneticist. With Matthew Meselson, Stahl conducted the famous Meselson-Stahl experiment showing that DNA is replicated by a semiconservative mechanism, meaning that each strand of the DNA serves as a template for production of a new strand. He is Emeritus Professor of Biology at the University of Oregon's Institute of Molecular Biology in Eugene, Oregon. Career Stahl, like his two older sisters, graduated from the public schools of Needham, a Boston suburb. In 1951, he was awarded an AB degree in biology from Harvard College, and matriculated in the biology department of the University of Rochester. His interest in genetics was cemented in 1952 by his introduction to bacterial viruses (phages) in a course taught by A. H. (Gus) Doermann at the Cold Spring Harbor Biological Laboratory. In 1956, he received a PhD in biology for his work with Doermann on the genetics of T4 phage. In 1955, ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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DNA Replication
In molecular biology, DNA replication is the biological process of producing two identical replicas of DNA from one original DNA molecule. DNA replication occurs in all living organisms acting as the most essential part for biological inheritance. This is essential for cell division during growth and repair of damaged tissues, while it also ensures that each of the new cells receives its own copy of the DNA. The cell possesses the distinctive property of division, which makes replication of DNA essential. DNA is made up of a double helix of two complementary strands. The double helix describes the appearance of a double-stranded DNA which is thus composed of two linear strands that run opposite to each other and twist together to form. During replication, these strands are separated. Each strand of the original DNA molecule then serves as a template for the production of its counterpart, a process referred to as semiconservative replication. As a result of semi-conservative rep ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Semiconservative Replication
Semiconservative replication describe the mechanism of DNA replication in all known cells. DNA replication occurs on multiple origins of replication along the DNA template strand (antinsense strand). As the DNA double helix is unwound by helicase, replication occurs separately on each template strand (sense strand) in antiparallel directions. This process is known as semi-conservative replication because two copies of the original DNA molecule are produced, each copy conserving (replicating) the information from one half of the original DNA molecule. Each copy contains one original strand and one newly-synthesized strand. (Both copies should be identical, but this is not entirely assured.) The structure of DNA (as deciphered by James D. Watson and Francis Crick in 1953) suggested that each strand of the double helix would serve as a template for synthesis of a new strand. It was not known how newly synthesized strands combined with template strands to form two double helical DNA m ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Franklin Stahl
Franklin (Frank) William Stahl (born October 8, 1929) is an American molecular biologist and geneticist. With Matthew Meselson, Stahl conducted the famous Meselson-Stahl experiment showing that DNA is replicated by a semiconservative mechanism, meaning that each strand of the DNA serves as a template for production of a new strand. He is Emeritus Professor of Biology at the University of Oregon's Institute of Molecular Biology in Eugene, Oregon. Career Stahl, like his two older sisters, graduated from the public schools of Needham, a Boston suburb. In 1951, he was awarded an AB degree in biology from Harvard College, and matriculated in the biology department of the University of Rochester. His interest in genetics was cemented in 1952 by his introduction to bacterial viruses (phages) in a course taught by A. H. (Gus) Doermann at the Cold Spring Harbor Biological Laboratory. In 1956, he received a PhD in biology for his work with Doermann on the genetics of T4 phage. In 1955 ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Molecular Biologist
Molecular biology is the branch of biology that seeks to understand the molecular basis of biological activity in and between cells, including biomolecular synthesis, modification, mechanisms, and interactions. The study of chemical and physical structure of biological macromolecules is known as molecular biology. Molecular biology was first described as an approach focused on the underpinnings of biological phenomena - uncovering the structures of biological molecules as well as their interactions, and how these interactions explain observations of classical biology. In 1945 the term molecular biology was used by physicist William Astbury. In 1953 Francis Crick, James Watson, Rosalind Franklin, and colleagues, working at Medical Research Council unit, Cavendish laboratory, Cambridge (now the MRC Laboratory of Molecular Biology), made a double helix model of DNA which changed the entire research scenario. They proposed the DNA structure based on previous research done by Ro ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Geneticist
A geneticist is a biologist or physician who studies genetics, the science of genes, heredity, and variation of organisms. A geneticist can be employed as a scientist or a lecturer. Geneticists may perform general research on genetic processes or develop genetic technologies to aid in the pharmaceutical or and agriculture industries. Some geneticists perform experiments in model organisms such as ''Drosophila'', ''C. elegans'', zebrafish, rodents or humans and analyze data to interpret the inheritance of biological traits. A basic science geneticist is a scientist who usually has earned a PhD in genetics and undertakes research and/or lectures in the field. A medical geneticist is a physician who has been trained in medical genetics as a specialization and evaluates, diagnoses, and manages patients with hereditary conditions or congenital malformations; and provides genetic risk calculations and mutation analysis. Education Geneticists participate in courses from many are ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Lasker Award
The Lasker Awards have been awarded annually since 1945 to living persons who have made major contributions to medical science or who have performed public service on behalf of medicine. They are administered by the Lasker Foundation, which was founded by Albert Lasker and his wife Mary Woodard Lasker (later a medical research activist). The awards are sometimes referred to as "America's Nobels". The Lasker Awards have gained a reputation for identifying future winners of the Nobel Prize. Eighty-six Lasker laureates have received the Nobel Prize, including 32 in the last two decades. Claire Pomeroy is the current president of the Lasker Foundation. Award The award is given in four branches of medical science: # Albert Lasker Basic Medical Research Award # Lasker-DeBakey Clinical Medical Research Award # Lasker-Bloomberg Public Service Award (Renamed in 2011 from Mary Woodard Lasker Public Service Award. Renamed in 2000 from Albert Lasker Public Service Award.) # ''Lasker-Koshl ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Thomas Hunt Morgan Medal
The Thomas Hunt Morgan Medal is awarded by the Genetics Society of America (GSA) for lifetime contributions to the field of genetics. The medal is named after Thomas Hunt Morgan, the 1933 Nobel Prize winner, who received this award for his work with Drosophila and his "discoveries concerning the role played by the chromosome in heredity." Morgan recognized that Drosophila, which could be bred quickly and inexpensively, had large quantities of offspring and a short life cycle, would make an excellent organism for genetic studies. His studies of the white-eye mutation and discovery of sex-linked inheritance provided the first experimental evidence that chromosomes are the carriers of genetic information. Subsequent studies in his laboratory led to the discovery of recombination and the first genetic maps. In 1981 the GSA established the Thomas Hunt Morgan Medal for lifetime achievement to honor this classical geneticist who was among those who laid the foundation for modern genetic ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Genetics Society Of America
The Genetics Society of America (GSA) is a scholarly membership society of more than 5,500 genetics researchers and educators, established in 1931. The Society was formed from the reorganization of the Joint Genetics Sections of the American Society of Zoologists and the Botanical Society of America. An Abridged History of the Genetics Society of America GSA members conduct fundamental and applied research using a wide variety of s to enhance understanding of living systems. Some of the systems of study include '''' (fruit flies), '' [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |