BIOL 2124 Lecture Notes - Lecture 2: Picometre, Crystallography, Drug Design
Document Summary
Optics for biologists: what we want from a microscope: resolution - the ability to see detail (can you distinguish two points as separate from one another, contrast - the ability to distinguish an object from its background. Resolution: magnification without resolution = bigger, just as blurry picture, the more resolution, the more you can discern about the objects (the separate rings of saturn) Contrast: the ability to differentiate what you"re looking at from the background. Independent of magnification and resolution: both pictures on the right have high contrast. Light microscopes tend to be best for cells and bacteria: electron microscopes for viruses, details on organelles, and anything smaller, a good rule of thumb is micrometers for light microscopes and nanometers for electron microscopes. Electron microscopy preparation: scanning electron microscopy (sem, dehydrate sample, coat in a thin layer of metal, sample goes in a vacuum, transmission electron microscopy (tem, dehydrate sample, embed in plastic, thinly sliced, sample goes in a vacuum.
