Microscopy

• Preparing a microscope slide


  • Specimens must be prepared carefully to avoid damaging them
  • The most common specimens used are cheek cells (animals) and onion cells (plants)
  • Stains are used to highlight structures in cells
  • methelene blue - cheek cells
  • iodine - onion cells
• Using a microscope


  • clip the slie carefully onto the stage
  • ensure the lowest-powered objective lens is over the slide
  • ise tje cparse adjustment knob to bring the stage up to just below the lens
  • look dow the eyepiece and gradually move the stage downwards until the image is in focus
  • to focus the image, adjust the fine-adjustment knobS
• Increasing magnification


  Change the objective lens to a higher power
• Biological drawings 


  • always draw with a sharp pencil
  • draw structures in proportion
  • label all features
• Magnification = image / real