1. Microscopes Microscopes

2. Importance One of the most widely used tools in Biology One of the most widely used tools in Biology Produces enlarged images of objects Produces enlarged images of objects Microscope animation Microscope animation Microscope animation Microscope animation

3. Microscopy Terms Magnification – the increase in an object’s apparent size Magnification – the increase in an object’s apparent size Resolution – the power of a microscope to clearly show detail Resolution – the power of a microscope to clearly show detail Clarity Clarity Focus Focus

4. TYPES OF MICROSCOPES Compound Light Microscope Compound Light Microscope Electron Microscopes Electron Microscopes

5. Compound Light Microscope Compound Light Microscope Thin sliced and sometimes stained specimen is mounted on a slide to be viewed Thin sliced and sometimes stained specimen is mounted on a slide to be viewed Uses a light source (a light bulb or mirror) Uses a light source (a light bulb or mirror) Light passes through the specimen and through the objective lens Light passes through the specimen and through the objective lens total magnification= power of magnification of objective lens x the power of magnification of the ocular lens total magnification= power of magnification of objective lens x the power of magnification of the ocular lens Ex. 40 X 10 = 400X total magnification Ex. 40 X 10 = 400X total magnification

6. Limitations of Compound Light Microscopes The Resolution decreases as Magnification increases The Resolution decreases as Magnification increases

7. Electron Microscopes Electron Microscopes Able to view extremely small objects Able to view extremely small objects Uses a Beam of Electrons, rather than light to produce an enlarged image Uses a Beam of Electrons, rather than light to produce an enlarged image Electron microscopes are more powerful than LM's Electron microscopes are more powerful than LM's There are several types of electron microscopes There are several types of electron microscopes

8. Transmission Electron Microscope (TEM) Can magnify objects up to 200,000 X Can magnify objects up to 200,000 X Projects image onto a screen or photographic plate Projects image onto a screen or photographic plate Greatly magnifies internal details of a specimen Greatly magnifies internal details of a specimen Cannot be used to view living specimens Cannot be used to view living specimens

9. (TEM)

10. Scanning Electron Microscope (SEM) Produces a 3-D image Produces a 3-D image Produce magnified image of surface details Produce magnified image of surface details Can magnify up to 100,000 times Can magnify up to 100,000 times Can not be used to view living specimens Can not be used to view living specimens A beam of electrons is passed over the surface of a metal coating A beam of electrons is passed over the surface of a metal coating Showered electrons are projected onto a fluorescent screen or photographic plate Showered electrons are projected onto a fluorescent screen or photographic plate

11. (SEM)