Advanced Biology 11
History of Cell Theory
History of the Microscope
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First invented; 1590, Hans and Zacharias Janssen (originally 3X to 9X), Dutch eye glass makers
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Anton Van Leeuwenhoek, 1632-1723, designed the best simple microscopes of the time, first person to
describe bacteria and protozoans
Discovery of the Cell
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1665: Robert Hooke, English scientist, described the spaces in cork as cells. He first coined the term cell
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1674: Anton Van Leeuwenhoek, Holland, first describes protozoans
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1824: Henry Dutrochet, France, proposed that all living things were composed of cells and discovered that
plants grew by increasing their number of cells.
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1831, Robert Brown, Scotland, described the nucleus as a small-round-dense body common to all plant
cells.
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**1838, Matthais Schleiden, Germany, after a lengthy study concluded that all plants are made of cells.
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**1839, Theodor Schwann, Germany, concluded that all animals are made of cells.
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1839, Johannes Purkinje, Czech Republic, used the term ‘protoplasm’ in reference to the jelly-like material
with in a cell.
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1858, Rudolph Virchow, Germany, stated that all cells come from other living cells.
Cell Theory
1.
All organisms are made of cells or cell fragments
2.
The cell is the basic unit of structure and function in organisms.
3.
Cells are produced from other living cells
Continued Discoveries
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1857: Kolliker, described the mitochondria
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1869: Miescher isolated DNA for the first time.
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1879: Flemming described chromosome behavior during mitosis.
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1898: Golgi described the golgi apparatus.
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1953: Crick, Wilkins and Watson proposed structure of DNA double-helix.