Biology 2382B Study Guide - Midterm Guide: Differential Interference Contrast Microscopy, Phase-Contrast Microscopy, Immunofluorescence

• School: Western University
• Department: Biology
• Course: Biology 2382B
• Professor: Robert Cumming

Document Summary

40-1000x magnification: total magnification is a product of the ocular and objective lens. Can"t resolve between objects that are less than 0. 2 micrometer apart (cid:523)200 nm(cid:524) To achieve contrast: cells themselves will slow light down = dim spot, artificially slow down this light down even further by superimposing waves. Crest + trough = neutralize = dimmer spot = lower intensity of light. Refracted light passes through phase plate (filter) slowing it down of a wavelength. Small differences in refractive index and thickness within the cell are exploited and converted to visible contrast to the eye. Get more dark spots to reveal intracellular constituents. Makes contrast based on combining polar wave forms of light using polarizers: creates contrasts by interfering with the polarity of light. Small differences in refractive index and thickness within the cell are converted into contrast visible to the eye using polarized light.