Introduction

In laboratory 1 you examined eukaryotic cells with the light microscope. The invention of the electron microscope with its subsequent application to biological materials in the 1930's gave new impetus to the study of cellular structure. An electron microscope utilizes an electron beam instead of a light beam, while the lenses are electromagnets instead of glass. The main advantage of the electron microscope is in its greater resolution, with objects in the order of 50 or 60 nanometers being visualized compared with one micrometer maximum resolution with the light microscope. The electron microscope has allowed us to visualize subcellular structure and in conjunction with biochemical studies we are now able to ascribe functions to these structures.