Molecular biology

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Molecular biology is the scientific study of the molecular basis of life processes, including cellular respiration, excretion, and reproduction. This branch of biology deals with the nature of biological phenomena at the molecular level through the study of DNA and RNA, proteins, and other macromolecules involved in genetic information and cell function, characteristically making use of advanced tools and techniques of separation, manipulation, imaging, and analysis.

The term molecular biology was coined in 1938 by Warren Weaver, then director of the natural sciences program at the Rockefeller Foundation. In 1950 W. T. Astbury of the University of Leeds used the term in its now accepted sense, to describe the area of research, closely related to and often overlapping biochemistry, conducted by biologists whose approach to and interest in biology are principally at the molecular level of organization. The field of molecular biology has grown with the increasing sophistication of available techniques and has quickly built upon its own increases in the understanding of biological processes. In the 1930s, with the help of the technique of ultracentrifugation, the macromolecules were first studied in detail and their crystalline properties described. In the 1940s the process by which individual genes produce their unique products began to be understood as resulting from the different sequences of the base pairs that make up the genes.

In the 1950s Linus Pauling described the three-dimensional structure of proteins, and James Watson and Francis Crick described the double helix of the DNA molecule. Further advances were made in understanding DNA, protein, and virus synthesis and the regulation of genes, and by the 1970s, the techniques of genetic engineering were enabling molecular biologists to study higher plants and animals, opening up the possibility of manipulating plant and animal genes to achieve greater agricultural productivity. Such techniques also opened the way for the development of gene therapy.

And no, no matter what you've heard molecular biology doesn't prove Noah's ark, that evolution of new species is impossible or that Ken Ham has an exceptional brain.

Timeline of molecular biology discoveries[edit]

The chief discoveries of molecular biology took place in a period of only about twenty-five years.

Date Event
1940 George Beadle and Edward Tatum demonstrated the existence of a precise relationship between genes and proteins. In the course of their experiments connecting genetics with biochemistry, they switched from the genetics mainstay Drosophila melanogaster to a more appropriate model organism, the fungus Neurospora crassa; the construction and exploitation of new model organisms would become a recurring theme in the development of molecular biology.
1944 Oswald Avery, working at the Rockefeller Institute of New York, demonstrated that genes are made up of DNA.
1952 Alfred Hershey and Martha Chase confirmed that the genetic material of the bacteriophage, a virus which infects bacteria, is made up of DNA.
1953 James Watson and Francis Crick discovered the double helical structure of the DNA molecule.
1960 Rene Dubos works on antimicrobial agents and environmental protection. F. M. Burnet and Peter B. Medawar receive Nobel Prize for the discovery of acquired immunological tolerance.
1960 "Ames Test" to screen for mutagens developed by Bruce Ames.
1961 Francois Jacob and Jacques Monod hypothesized the existence of an intermediary between DNA and its protein products, which they called messenger RNA.
1961-1965 The relationship between the information contained in DNA and the structure of proteins was determined: there is a genetic code, which creates a correspondence between the succession of nucleotides in the DNA sequence and a series of amino acids in proteins. Monod and Jacob also demonstrated how certain specific proteins, called regulative proteins, latch onto DNA at the edges of the genes and control the transcription of these genes into messenger RNA; they direct the "expression" of the genes.
1973 Herbert Boyer and Stanley Cohen, using plasmids, are the first to clone DNA.
1976 Michael Bishop and Harold Varmus discover the cancer-causing genes, called oncogenes, and find that such genes are in normal tissues.
1978 Daniel Nathans, H.O. Smith and Werner Arber receive Nobel Prize for using restriction enzymes to map viral genomes.
1982 Stanley Prusiner isolates a protein from a slow disease infection and suggests that it might direct its own replication. He suggests the agent be termed a prion.
1983 Luc Montagnier of France and Robert Gallo of the United States independently isolate and characterize the human immunodeficiency virus (HIV) the cause of AIDS.
1983 Kary Mullis invents the polymerase chain reaction.
1983 Barbara McClintock receives the Nobel Prize for discovery of mobile genetic elements.
1994 The Food and Drug Administration approves the first genetically engineered food for human consumption, a slower ripening tomato.
1995 The Food and Drug Administration approves the first protease inhibitor, a major weapon against the progression of AIDS. Homophobes are disappointed.
1996 Peter C. Doherty and Rolf M. Zindernagel receives Nobel Prize for the discovery of how the immune system recognizes virus-infected cells.
1997 The first complete nucleotide sequence of all of the chromosomes of a eukaryote is reported (yeast).
1999 Ford Doolittle proposes that evolution proceeded with Horizontal gene transfer between the three domains. That doesn't mean humans are a bacteria, don't make that claim at a cocktail party.
2003 The Human Genome Project was declared completed. Though newer drafts and revisions have been published since then.
2006 Andrew Fire and Craig Mello win the Nobel Prize for their discovery of RNA interference.
2007 James Watson declares Europeans are more intelligent than Africans.[1] Most Europeans cringe while Africans have heard such garbage so many times they hardly blink.

See also[edit]