Electron microscopy of organelles

Abstract 1. Introduction The electron microscope has made major contributions to our understanding of tissues, cells, and organelles and how they function. Electron microscopes have become widespread in their use and are a reliable means of examining biological structures. The process of producing sections using a microtome (microtomy) is also reliable provided that the samples are adequately prepared and embedded. Electron microscopy enables these samples to be examined with a high degree of resolution of approx. 1 nm which is much greater than that of optical microscopy which is limited by the intrinsic properties of light. A further fundamental difference between optical and all forms of electron microscopy is that optical microscopical techniques for examining large quantities of potentially living specimens exist whilst the electron microscope is capable of examining only relatively small quantities of exclusively dead and artefactually transformed specimens.