THE MICROSCOPE
Invention of the Microscope The microscope was invented by Zacharias Jansen and his father (a pair of 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.
Invention of the Microscope In 1665, Robert Hooke examined a thin piece of cork under the microscope and noticed that it seemed to be made of thousands of tiny empty chambers which Hooke called “cells” because they reminded him of the small rooms of a monastery called cells.
Invention of the Microscope At about the same time, the Dutchman Anton van Leeuwenhoek used a microscope to observe pond water. The microscope revealed a world of tiny living organsims.
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 There are 2 types of electron microscopes: Transmission Electron Microscopes (TEM) pass electrons through a thin slice of an object Scanning Electron Microscopes (SEM) examine the outside of an object by bouncing electrons off the surface TEM of mitochondria SEM of blood cells
Electron Microscope (cont.) The advantage of this microscope is that they can magnify objects up to one million times their actual size The disadvantage of this microscope is that specimens must be fixed in position and placed in a vacuum so organisms can not be alive
Resolution The ability to distinguish between two points The better the resolution, the sharper the image
Dyes Used to color a specimen and thus improve the contrast between different parts of a specimen Staining, however, usually kills the specimen
Magnification Makes the image look larger To find the magnification, multiply the magnification of the ocular lens by the magnification of the objective lens EX: 4x objective and a 10x ocular lens will give a magnification of 40x