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Invention of the Microscope Invention of the Microscope • The microscope was invented by a trio of Dutch eyeglass makers in the late 1500s and magnified objects up to 9x • The invention of the microscope allowed scientists to view cells for the first time. • In 1665, Robert Hooke published his drawings of cells, but these were the cell walls of cork cells; the cells were no longer living • In the early 1670s, Anton van Leeuwenhoek was the first person to examine living cells Types of Microscopes Types of Microscopes • There are two types of microscopes: – Light microscopes – Electron microscopes Light Microscope Light Microscope • Uses either sunlight or artificial light to view objects. • The object being viewed must be thin enough for light to pass through. • The advantage of a light microscope is that it can magnify many microscopic organisms while they are still alive. • The disadvantage of this microscope is that it can only magnify about 1000x. Electron Microscope Electron Microscope • These microscopes either: –pass electrons through a thin slice of an object (transmission electron microscope or TEM) –examine the outside of an object (scanning electron microscope or SEM) • The advantage of this microscope is that they can magnify objects up to one million times their actual size. Electron Microscope (cont.) Electron Microscope (cont.) • The biggest disadvantage of this microscope is that specimens must be fixed in position and placed in a vacuum so organisms can not be alive.
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