Required Practical 1: Microscopes

• What is the main part of the optical microscope where the slide is placed?

  The stage
• What is the function of the lamp in an optical microscope?

  To illuminate the microscope slide
• What is used in some optical microscopes instead of a lamp?

  A mirror
• What are the lenses above the stage called?

  Objective lenses
• What are the typical magnifications of the objective lenses?

  Four times, ten times, or 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
• What should you do after placing the slide on the stage?

  Use clips to hold the slide in place
• Which objective lens should you select first for viewing?

  The lowest power objective lens
• Why is it important to look at the microscope from the side while adjusting the objective lens?

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

  Look through the eyepiece and adjust focus
• What is the purpose of the fine focusing dial?

  To bring the cells into clear focus
• How do you calculate the total magnification of the microscope?

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

  Forty 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 the microscope?

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

  Cell wall, cytoplasm, and nucleus
• How do you create a magnification scale for your drawing?

  Measure the diameter of the field of view