Microscopes History, Parts, and Usage

History of the Microscope Anton van Leeuwenhoek (mid 1600s) –“father of microscopy” –looked at water through a simple light microscope (one lens, natural light)

History of Microscopes Robert Hooke (1665) –Used a compound light microscope (series of lenses, up to 1500x magnification) –Looked at cork (dead oak cells) –Saw geometric shapes  named them “cells”

History of Microscopes Matthias Schleiden (1830s) –Concluded that all plants are made of cells Theodore Schwann (1830s) –Concluded that all animals are made of cells

History of Microscopes Cell Theory –All organisms are composed of one or more cells. –The cell is the basic unit of organization in organisms. –All cells come from pre-existing cells.

History of Microscopes Electron Microscope (1940s) –Uses beam of electrons instead of light –Magnifies up to 500,000x –Two types: Scanning electron microscope (SEM) –See surfaces in 3D Transmission electron microscope (TEM) –See structures inside cells

History of Microscopes

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

Compound Microscope Parts

Microscope Usage To calculate total magnification of microscope: eyepiece x objective (Eyepiece always 10x.) Example: If objective lens is set on 4x, what is the total magnification of the microscope?

Microscope Usage Always carry microscope with one hand on the arm and one hand on the base. Always look to the SIDE when LOWERING the objectives. Always begin viewing specimen on the LOWEST power, then work up. The coarse adjustment must only be used on the LOWEST power. Use fine adjustment on higher powers.