GT

I. A Tour of the Cell A. All living organism have cell. B. Microscopes provide windows to the world of the cell. 1. A light microscope is the first microscope and it works by passing visible light through a specimen. 2. Then Electron microscope came that uses beam of light. It’s much powerful then the light microscope about small as 1nm can be seen. Then scanning electron microscope came out to study the detailed architecture of cell surface. It also uses electron beam to scan the surface of a cell or group of cells that have been coated with metal. 3. Transmission electron microscope is used to study the details of internal cell structure. With the cut specimens the electromagnets bend the electron beams to magnify and focus an image onto a viewing screen or photo.