Word: molecular
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Perhaps it was simply a matter of chance, a random throw of the molecular dice. Perhaps some greater, transcendent force was at work in the earth's primeval seas. Yet from the moment of its miraculous genesis three billion years ago, life has been continually renewing and remaking itself, an evolutionary process that has led to the appearance of a unique creature quite unlike any of those before him. Thinking, feeling, striving, man is what Pierre Teilhard de Chardin called "the ascending arrow of the great biological synthesis...
...unraveling of the DNA double helix was one of the great events in science, comparable to the splitting of the atom or the publication of Darwin's Origin of Species. It also marked the maturation of a bold new science: molecular biology. Under this probing discipline, man could at last explore?and understand?living things at their most fundamental level: that of their atoms and molecules. Once molecular biology was sardonically defined as "the practice of biochemistry without a license." Now it has become one of science's most active, exciting and productive arenas, taking the limelight (and some...
...Molecular biology, in part, is rooted in the science of genetics. Ever since Cro-Magnon man, parents have probably wondered why their children resemble them. But not until an obscure Austrian monk named Gregor Mendel began planting peas in his monastery's garden in the mid-19th century were the universal laws of heredity worked out. By tallying up the variations in the offspring peas, Mendel determined that traits are passed from generation to generation with mathematical precision in small, separate packets, which subsequently became known as genes (from the Greek word for race...
...1940s, however, the molecular biologists had come on the scene, and they insisted that fundamental life processes could be fully understood only on the molecular level. In their investigations, some used the electron microscope, which revealed details of structure invisible to ordinary optical instruments. Others specialized in X-ray crystallography, a technique for deducing a crystallized molecule's structure by taking X-ray photographs of it from different angles. Physicist Max Delbrück turned to nature for his investigative tools: bacteriophages (literally, "bacteria eaters"), tiny parasitic viruses that invade their host bacteria and rob them of their genetic heritage...
...shape of a helix, or spiral. From the X-ray crystallography laboratory at King's College in London, where Biochemist Maurice Wilkins was also investigating the molecule's structure, they quietly obtained unpublished X-ray data on DNA. Relying as much on luck as logic, they constructed Tinkertoy-like molecular models out of wire and other metal parts. To everyone's astonishment, they suddenly produced a DNA model that not only satisfied the crystallographic evidence but also conformed to the chemical rules for fitting its many atoms together...