The document discusses the history and types of microscopes. It notes that the first compound microscope was invented in 1590 and that Robert Hooke used one in 1655 to observe and name plant cells. Later, Antoine van Leeuwenhoek used a microscope to observe single-celled organisms. The document defines magnification and resolution as important factors for microscopes and describes the two main types - compound light microscopes, the most widely used, and electron microscopes, which use beams of electrons and can provide much higher magnification for very small objects like viruses.

1. Microscopes
Section 3-1

2. History of the Microscope
• 1590 –first compound
microscope

3. 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
• Antoine van Leeuwenhoek
–1st
to see single-celled
organisms in pond water

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

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

8. Ocular lens
Objective
lenses

9. 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

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

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