BIO SCI 93 Chapter Notes - Chapter 6: Electron Microscope, Cytoskeleton, Antibody

• School: UC-Irvine
• Department: Biological Sciences
• Course: BIO SCI 93
• Professor: Justin Shaffer

Document Summary

Magnification: ratio of an object"s image size to its real size. Resolution: measure of clarity of the image; minimum distance 2 points can be separated & still be distinguished as separate points. Contrast: difference in brightness between the light and dark areas of an image. Rather than focusing light, electron microscope focuses beam of electrons through the specimen or onto its surface. Light passes directly through specimen; unless stained, has very little contrast. Variations in density within specimen amplified to enhance contrast in unstained cells. Light molecules in cell revealed by labeling molecules with fluorescent dyes or antibodies. Uses a laser/ optical sectioning technique that eliminates materials in a cell (nuclear material, mitochondri a, organelles, etc. ) D reconstructi on can be created through image of different planes. Can see 3-d details of a plane of a cell out-of-focus light from a thick sample, creating single plane of fluorescence in the image.