Microscopy

• Common calculations in microscopy:

  • Magnification of a light microscope: magnification of the eyepiece lens x magnification of the objective lens
  • Size of an object: size of image/magnification = size of object (this formula can be rearranged to obtain the other values, make sure you are in the same units)
• Electron microscopes have a higher magnification and resolving power than light microscopes
• Microscopes like light microscopes and electron microscopes are used to view cells and sub-cellular structures
• Standard form can be useful when working with very large or small numbers, allowing for easier comparison of numbers by multiplying a certain number by a power of 10
• Common calculations in microscopy include the magnification of the eyepiece lens and the objective lens
• Orders of magnitude are used to understand the relative sizes of cells and organelles, where a difference of 10 times indicates a difference of 10^1 times bigger or 10^-1 times smaller
• Prefixes go before units of measurement to show the multiple of the unit, for example:

  • Centi: 0.01
  • Milli: 0.001
  • Micro: 0.000,001
  • Nano: 0.000,000,001
• Parts of a light microscope:

  • Eyepiece: where specimens are viewed
  • Barrel: moved up or down to focus the image
  • Turret: rotated to change the magnification lens
  • Lens: increases the magnification of the specimen
  • Stage: flat surface where the specimen is placed
• Steps to prepare a slide for a light microscope:

  1. Take a thin layer of cells from the sample

  2. Add the correct chemical stain to make parts of the specimen more visible

  3. Apply the cells to a glass slide

  4. Carefully lower a coverslip onto the slide to avoid air bubbles