1. Microscopes Section 2.2

2. History and use of the microscope http://www.youtube.com/watch?v=ZYNThPzh03c

3. History of the Microscope Antoine van Leeuwenhoek 1 st to see single-celled organisms in pond water

4. History of the Microscope 1655 – Robert Hooke used a compound microscope to observe pores in cork He called them “cells”

5. History of the Microscope 1590 –first compound microscope

7. Microscope Vocabulary Magnification: increase of an object’s apparent size Resolution: power to show details clearly Both are needed to see a clear image

8. Types of Microscopes 1. Compound Light Microscope 1 st type of microscope, most widely used light passes through 2 lenses Can magnify up to 2000x

9. Ocular lens Objective lenses

10. Types of Microscopes 2. Electron Microscope Used to observe VERY small objects: viruses, DNA, parts of cells Uses beams of electrons rather than light Much more powerful

11. Types of Microscopes Transmission Electron Microscope (TEM) Can magnify up to 250,000x

14. Types of Microscopes Scanning Electron Microscope (SEM) Can magnify up to 100,000x

17. Parts of a Microscope http://www.youtube.com/watch?v=KzNsu iqW1LQ

19. How to use a microscope http://www.youtube.com/watch?v=X-w98KA8UqU