BIOL 3200 Lecture Notes - Microscopy, Desulfovibrio, Flagellin
Document Summary
Chapter 3 microscopy and cell structure: microscopes, most important tool for studying microorganisms, use visable light to observe objects, magnify images approx. 1,000x: electron microscope (1931) can magnify images in excess of. 100,000x: atomic-force microscope (1981) can view individual atoms, light microscopy, light passes through specimen, then through series of magnifying lenses, most common and easiest to use is the bright-field, magnification, microscope has two magnifying lenses. Lens include ocular lens and objective lens: lenses combine to enlarge objects. Magnification iis equal to the factor of the ocular x the objective: brightfield microscope. Uses light condenser to concentrate light on sample: usefulness of microscope depends on its ability to resolve two objects that are very close together. Resolving power is defined by the minimum distance between two objects: resolution, contrast, darkfield microscope. Reverse image: reflects the number of visible shades in a specimen, higher contrast achieve for microscopy through specimen staining, examples of light microscopes that increase contrast, phase-contrast microscope.