Stages Of Mitosis

• Mitosis


  The process of cell division in plant cells, occurring at shoot and root tips in areas called meristems
• Meristems


  • Plant cells in the meristems are totipotent and retain the ability to differentiate
  • The mitotic index of a sample is the ratio of cells undergoing mitosis to the total number of cells in the sample. To find the mitotic index, cells from the meristems must be viewed under an optical microscope
• Mitotic index = number of cells with visible chromosomes / total number of cells in sample
• Equipment

  • Garlic Root tip
  • Toluene blue stain
  • Watch glasses
  • Microscope slides and covers lips
  • 1M hydrochloric acid
  • Distilled water
  • Sample tube
  • Filter paper
  • Forceps
  • Scissors
  • Pipettes
  • Optical microscope
• Practical 5


  1. Cut a 5mm sample of the root tip using a scalpel

  2. Place the root tips in tubes containing HCl and leave for 5 minutes

  3. Place the root tips on a watch glass containing cold distilled water and leave for 5 minutes

  4. Dry the root tips on filter paper

  5. Place the root tip on a microscope slide and macerate with a needle to spread the cells out

  6. Add a drop of toluidine blue stain and leave for 2 minute

  7. Lower the coverslip carefully onto the slide, ensuring no air bubbles that would distort the image

  8. Wrap in a paper towel and squash the slide gently

  9. Observe using a microscope with objective lens set to lowest magnification

  10. Use coarse adjustment knob to re-adjust focus till image is clear
• This makes the chromosomes visible and shows cells undergoing mitosis