Microscopy Required Practical 1

• What is the aim of the microscopy investigation described?

  To use a light microscope to investigate a selection of plant and animal cells.
• What equipment is needed for the microscopy investigation?

  • Light microscope
  • Microscope slide
  • Cover slip
  • Onion
  • Forceps
  • Iodine solution
  • White tile
  • Scalpel
  • Any other prepared plant and animal cell slides
• What is the first step in the microscopy method?

  Peel off an epidermal layer on the onion using forceps.
• How should the onion tissue be prepared on the microscope slide?

  Mount onto the microscope slide with a drop of water, ensuring the tissue lies flat.
• Why is iodine solution added to the cells on the slide?

  To stain the cells for better visibility under the microscope.
• What is the correct way to place the cover slip on the slide?

  Place one edge down on the slide and slowly lower the other side using forceps.
• What should be done if there is excess stain on the slide?

  Remove any excess stain by soaking it with paper towels.
• What is the first step to set up the microscope after placing the slide on the stage?

  Turn the nosepiece to select a low power objective.
• What should you do before looking into the eyepiece of the microscope?

  Use the coarse adjustment knob to raise the stage until the cover slip just touches the objective.
• What is the next step after looking into the eyepiece?

  Turn the coarse adjustment knob to move the stage away until the image comes into focus.
• What should be done after focusing with the low power objective?

  Turn the nosepiece to select a high power objective.
• What is the final step in focusing the image after switching to high power objective?

  Turn the fine adjustment knob until the image comes into focus.
• What should be included in the labelled drawing of the cells?

  • Features such as cell wall and nucleus
  • The magnification used for the observation
• What should be done after making the drawing of the cells?

  Repeat the steps using a prepared slide.
• What safety precautions should be taken when handling iodine solution?

  • Wear safety goggles
• What is the first step in the microscopy required practical?

  Peel off an epidermal layer on the onion using forceps.
• How should the onion tissue be prepared on the microscope slide?

  Mount onto the microscope slide with a drop of water, ensuring the tissue lies flat.
• Why is iodine solution added to the cells on the slide?

  To stain the cells for better visibility under the microscope.
• How should the cover slip be placed on the slide?

  Place one edge down on the slide and slowly lower the other side using forceps.
• What should be avoided when placing the cover slip on the slide?

  Trapping air bubbles.
• What should be done with excess stain on the slide?

  Remove it by soaking it with paper towels.
• Where should the slide be placed for observation?

  On the stage of the microscope.
• What is the first adjustment to make when setting up the microscope?

  Turn the nosepiece to select a low power objective.
• What should you do before looking into the eyepiece of the microscope?

  Use the coarse adjustment knob to raise the stage until the cover slip just touches the objective.
• What is the next step after raising the stage to touch the cover slip?

  Look into the eyepiece and turn the coarse adjustment knob to focus the image.
• What should be done after focusing with the low power objective?

  Turn the nosepiece to select a high power objective.
• What should you do after selecting the high power objective?

  Repeat the focusing process using the fine adjustment knob.
• What should you do after observing the cells under the microscope?

  Make a labelled drawing of the cells, including features like the cell wall and nucleus.
• What should be noted down when drawing the cells?

  The magnification used during observation.
• What should you do after completing the observation with the first slide?

  Repeat the steps using a prepared slide.