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Robert Hooke designed his own microscope and discovered matter made up of what he called cells.
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Antony van Leeuwenhoek discovered bacteria, free-living and parasitic microscopic protists, sperm cells, blood cells and more. All of this from a very simple device that could magnify up to 300X.
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C.F. Wolff proposed a general cell theory.
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Achromatic lenses introduced now provide resolution of 1 micron or 1/1000 mm
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Robert Brown names the cell nucleus and suggests its importance in fertillization
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Matthias J. Schleiden published a cell theory as applied to plants.
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Theodor Schwann and Matthias Schleiden formally propose the "Cell Theory."
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Theador Schwann published a work that had the first statement of cell theory: All living things are made up of cells.
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Donne' publishes the first micrographs in France.
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Robert Remak develops a method to isolate the cell membrane and proves it divides a cell
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Rudolf Virchow proposed that living cells come from pre-existiong cells
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Ernst Abbe made clear the difference between magnification and resolution. His widely used formula to calculate resolution is based on his wave light theory.
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Ernst Leitz microscope is introduced with a revolving mount (turret) for 5 objectives.
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Introduced oil immersion lens (cedar oil) that resulted in a homogeneous optical path.
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Walther Flemming discovers mitosis.
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August Kohler- Microscope lamp with filters worked out light source and condenser position to obtain the best image projection.
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microtomes begin to appear for sample preparation. Up to the point specimens were prepared by sharp knives.
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Walther Fleming used dyes to stain cells; he discovered rods he called “chromosomes.”
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Ernst Abbe designs apochromatic objective that brings red, yellow and blue into one focus
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Edouard van Beneden discovered that all organisms of the same species have the same number of chromosomes.
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Sutton proved that sperm and egg cells have one of each pair of chromosomes.
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The first commercial UV microscope by Zeiss.
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Fritz Zernike discovered he could view unstained cells using the phase angle of rays.
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Max Knoll and Ernst Ruska construct the first electron microscope.
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Ruska builds the first electron microscope that exceeds the resolution of the light microscope.
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First scanning electron microscope is built.
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Siemens supplies the first commercially available electron microscope.
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George W. Beadle and Edward L. Tatum discovered that genes control the production of enzymes.
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The Genetic code was discovered; scientists are now able to predict characteristics by studying DNA.
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Scanning Probe Microscope is invented and works by measuring current.
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Scanning laser confocal microscope is commercially available
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Atomic Force Microscope is invented and measures force instead of current.
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Three generations of mice were cloned from the nuclei of an adult, eight identical calves were cloned, the rough draft of the human genome map was produced.
