1. Microscopes

2. Simple Light Microscopes Contains one lens Uses light Used by Anton van Leeuwenhoek in the 1600s.

3. Compound Light Microscopes Use a series of lenses to magnify objects in steps. Can magnify objects up to 1500 times. Used by Robert Hooke to study cork cells.

4. Electron Microscopes Developed in the 1930s and 1940s. Uses a beam of electrons. Can magnify structures up to 500,000 times their original size. Because electrons can be scattered by air particles, objects must be viewed in a vacuum.

5. Electron Microscopes Scanning Electron Microscope (SEM) Scans the surface of cells to learn the 3D shape. Transmission Electron Microscope (TEM) Allows scientists to study the structures within a cell. Scanning Tunneling Microscope (STM) Creates computer images of atoms on the surface of a molecule.