BIOL 111 Chapter Notes - Chapter 3: Stereo Microscope, Electron Microscope, Photographic Film
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Magnified as it passes through glass lenses. Uses and electron beam passed through magnetic lenses. Uses two lenses: objective and ocular lenses. Contrast - differential absorption of light by different parts of the object being viewed. It can increase or decrease with proper adjustment or by staining the specimen. Staining can also increase the ability to identify specific structures within the specimen. (diameter of scanning lens)*(magnification of scanning lens)= (diameter of higher power lens)*(magnification of higher power lens) Under the microscope, specimen are upside down and reversed. Cytology - the study of cellular structure and function. Organelles - specialize in such functions as energy production, synthesis, and internal digestion. Photoautotrophic - blue-green algae, releasing oxygen as by-product of their photosynthesis. Nitrogen fixation - capturing of nitrogen gas (n2) from the air and its conversion/reduction to ammonia (nh3) Heterocyst - specialized cell, containing the necessary enzymes for these reactions.
