Electron microscopes have certain advantages over optical microscopes: The biggest advantage is that they have a higher resolution and are therefore also able of a higher magnification (up to 2 million times). Light microscopes can show a useful magnification only up to 1000-2000 times. This is a physical limit imposed by the wavelength of the light. Electron microscopes therefore allow for the visualization of structures that would normally be not visible by optical microscopy.
berm (plural berms) A narrow ledge or shelf, as along the top or bottom of a slope. A raised bank or path, especially the bank of a canal opposite the towpath. A terrace formed by wave action along a beach. A mound or bank of earth, used especially as a barrier or to provide insulation.
Princeton's WordNet(0.00 / 0 votes)Rate this definition: 1  berm(noun) a narrow ledge or shelf typically at the top or bottom of a slope. 2  shoulder, berm(noun) a narrow edge of land (usually unpaved) along the side of a road. the car pulled off onto the shoulder.