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History of science, the development of science over time. Humankind has long observed regularities in nature, from the movements of the Sun and Moon during day and night to the seasonal migrations of animals. Learn how science advanced from the observation of these natural phenomena to modern understanding.
Scientific Revolution is the name given to a period of drastic change in scientific thought that took place during the 16th and 17th centuries. It replaced the Greek view of nature that had dominated science for almost 2,000 years.
The chemical DNA was first discovered in 1869, but its role in genetic inheritance was not demonstrated until 1943. In 1953 James Watson and Francis Crick , aided by the work of biophysicists Rosalind Franklin and Maurice Wilkins , determined that the structure of DNA is a double-helix polymer , a spiral consisting of two DNA strands wound ...
Scientific understanding of viruses emerged in the 1890s, with the work of Russian microbiologist Dmitry I. Ivanovsky (1892) and Dutch microbiologist and botanist Martinus W. Beijerinck (1898). Both scientists were studying a disease of tobacco plants.
Cell theory, fundamental scientific theory of biology according to which cells are held to be the basic units of all living tissues. First proposed by German scientists Theodor Schwann and Matthias Jakob Schleiden in 1838, the theory that all plants and animals are made up of cells marked a great.
Most of the mechanisms of heredity, however, remained a mystery until the 19th century, when genetics as a systematic science began. Genetics arose out of the identification of genes, the fundamental units responsible for heredity.
Somewhere in the transition between the two, the hominid, the first humanlike species, emerges. By virtue of humanity’s nature as a toolmaker, humans have therefore been technologists from the beginning, and the history of technology encompasses the whole evolution of humankind.
Antonie van Leeuwenhoek, Dutch microscopist who was the first to observe bacteria and protozoa. His researches on lower animals refuted the doctrine of spontaneous generation, and his observations helped lay the foundations for the sciences of bacteriology and protozoology.
Dmitry Ivanovsky (born November 9 [October 28, Old Style], 1864, Nizy, Russia—died June 20, 1920, Rostov-na-Donu) was a Russian microbiologist who, from his study of mosaic disease in tobacco, first detailed many of the characteristics of the organisms that came to be known as viruses.
Amorphous elemental silicon was first isolated and described as an element in 1824 by Jöns Jacob Berzelius, a Swedish chemist. Impure silicon had already been obtained in 1811. Crystalline elemental silicon was not prepared until 1854, when it was obtained as a product of electrolysis.