Can a 20 μm diameter bacteria be seen with an electron microscope?

20 micrometers is not a very small size. It’s only 0.02 millimeters. Even in an ordinary optical microscope, you can see such a bacterium quite clearly and in detail. An electron microscope uses a beam of electrons instead of a light beam to examine a drug. Electron microscopes have a magnifying capacity of 1000 – 10000 times more than in a conventional microscope. But they are quite expensive and are used in the study of the structures of various substances or for the detailed study of viruses and bacteria by biologists, physicians and other specialists.