Microscopes

• What is the eyepiece graticule on a microscope?

  A fine scale that fits inside the eyepiece lense. Its units are arbitary.
• What is the stage micrometer on a microscope?

  A scale fitted on the coverslip. The size of the divisions are known.
• How are images produced on a scanning electron microscope?

  Electrons are reflected off the surface of the specimen
• Why are some structures darker than others through the transmission microscope?

  They're a denser material so appear darker
• What conditions are solutions under when being prepped to be viewed under a microscope?

  Tissue is chopped into an ice-cold, isotonic, buffered solution
• Why is the solution buffered during microscope preperation?

  Provides a constant pH to prevent enzymes/proteins from denaturing
• Why is the solution isotonic during microscope prep? [2]

  Solution and organelles will have the same water potential to prevent osmosis and the lysis (bursting) of organelles.