1. Microscopes

2. History Invented in the late 1500s – Compound microscope (2+ lenses) – Used natural light, magnified 20-30x

3. Robert Hooke (1665) Compound light microscope  viewed cork (dead oak cells) Viewed shapes  coined them “cells”

4. Antony van Leeuwenhoek (1600s) Father of microscopy and microbiology Built simple light microscope (one lens) – Improvement: 275x magnification Viewed water – Noticed Protists, worms, etc. Observed blood and sperm

6. Matthias Schleiden & Theodore Schwann Schleiden (1830s) – concluded all plants made of cells Schwann (1830s) – concluded all animals made of cells

7. Cell Theory All organisms composed of cells Cell = basic unit of organization in organisms All cells come from pre-existing cells

8. Electron Microscope (1940s) Beam of electrons instead of light Magnifies up to 500,000x 2 types – Scanning electron microscope (SEM) Surfaces in 3D – Transmission electron microscope (TEM) Structure inside cells

9. Scanning Tunneling Microscope (STM) See atoms on surface of molecules – 100,000,000x

10. Compound Light Microscope Lamp light 1500x Calculate Magnification: eyepiece x objective (always 10x) (varies) Example: Objective lens set to 4x, what is total magnification of microscope?