Required Practicals

• Preparing a slide:

  • add a drop of water to a clean slide
  • cut a thin slice of tissue
  • place tissue onto water on the slide
  • add iodine to stain the sample
  • place a coverslip
  • upright and lower to avoid air bubbles
• Microscopes

  • clip slide onto stage
  • switch light on and adjust mirror
  • select lowest power objective lens
  • use coarse adjustment knob to move stage as close to lens as possible
  • look down eyepiece lens and move stage down
  • adjust fine focus for clear image
  • greater magnification - use higher powered objective lens
• Osmosis

  • 5 different concentrations of sugar solution
  • cut identical cylinders
  • measure initial mass
  • place into each sugar solution and leave for 24 hrs
  • remove cylinders and dry
  • measure final mass
  • repeat and calculate a mean percentage change in mass
  • plot a graph