microscopy

• What should you be able to describe by the end of the video on using an optical microscope?

  How to use an optical microscope to look at cells on a prepared microscope slide
• Why is it important to learn the details of using an optical microscope?

  It could come up in the exam as a six mark essay question
• What is the main part of the optical microscope where the slide is placed called?

  The stage
• What is the purpose of the clips on the stage of the microscope?

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

  A lamp or a mirror
• How does the lamp function in an optical microscope?

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

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

  Three
• 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 called?

  The coarse focusing dial and the fine focusing dial
• What is the first step in using an optical microscope to view a prepared slide?

  Place the slide onto the stage and use the clips to hold it in place
• Which objective lens should be selected first when viewing a slide?

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

  Position it so it almost touches the microscope slide
• 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 down through the eyepiece and slowly turn the coarse focusing dial
• What is the purpose of the fine focusing dial?

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

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

  $40 \text{ times}$
• What should you do after achieving focus with the lowest power objective lens?

  Select a higher power objective lens, such as ten times
• What can you typically see when looking at animal cells under an optical microscope?

  The nucleons, cytoplasm, and cell membrane
• What additional structures might be visible in plant cells under an optical microscope?

  The cell wall, cytoplasm, nucleus, vacuole, and chloroplasts
• How do you include a magnification scale in your drawing of cells?

  Place a clear plastic ruler over the stage and measure the diameter of the field of view
• What should you write on your drawing besides the magnification scale?

  The magnification, for example, 100 times
• Where can you find questions related to the required practical on using an optical microscope?

  In the vision workbook
• Why is it important to learn the details of using an optical microscope?

  It is crucial for understanding practical applications in biology.
• What are some differences between various optical microscopes?

  Some use a lamp while others use a mirror to reflect light.
• What is the function of the coarse focusing dial?

  To adjust the distance between the objective lens and the slide.
• What is the function of the fine focusing dial?

  To bring the cells into a clearer focus.
• What types of cells can be observed under an optical microscope?

  Both animal and plant cells.
• What is the process for making a labeled drawing of cells?

  Use a pencil to draw and label the observed cells.
• Why is a scale bar significant in drawings of cells?

  It provides a reference for the size of the cells observed.
• Where can students find questions related to the required practical?

  In the vision workbook.