microscopy

• What should you be able to do by the end of the video?

  Describe using an optical microscope
• Why is it important to learn the details of using an optical microscope?

  It could appear in a six mark essay question
• What is the main part of the optical microscope where the slide is placed?

  The stage
• What is the function of the clips on the stage?

  To hold the slide in place
• What is located below the stage of an optical microscope?

  A lamp or mirror
• How does a mirror function in some optical microscopes?

  It reflects light up through the slide
• What are the lenses above the stage called?

  Objective lenses
• How many objective lenses do most microscopes have?

  Three different objective lenses
• What are the typical magnifications of objective lenses?

  Four times, ten times, forty times
• What is the magnification of the eyepiece lens?

  Ten times
• What are the two focusing dials on the microscope?

  Coarse and fine focusing dials
• What is the first step to view a prepared slide using an optical microscope?

  Place the slide onto the stage
• Which objective lens should be selected first?

  The lowest power objective lens
• How do you position the objective lens when starting to view a slide?

  Almost touch the microscope slide
• Why should you look at the microscope from the side while adjusting the lens?

  To avoid damaging the slide
• What should you do after positioning the objective lens?

  Look down through the eyepiece
• What is the purpose of the coarse focusing dial?

  To increase distance between lens and slide
• How do you achieve a clear focus on the cells?

  Use the fine focusing dial
• How do you calculate total magnification?

  Multiply eyepiece magnification by objective magnification
• What is the total magnification when using a ten times eyepiece and a four times objective lens?

  $40 \text{ times}$
• What should you do after selecting a higher power objective lens?

  Adjust the fine focusing dial again
• What can you see when looking at animal cells under an optical microscope?

  Nucleus, cytoplasm, and cell membrane
• What might you see when looking at plant cells under an optical microscope?

  Cell wall, cytoplasm, and nucleus
• What additional structures may be visible in plant cells?

  Vacuole and chloroplasts
• What should be included in your drawing of cells observed under a microscope?

  • Clear labeled drawing of cells
  • Magnification scale
  • Diameter of field of view in mm
  • Magnification written (e.g., 100 times)
• How do you create a magnification scale for your drawing?

  Measure diameter of field of view in mm