Microscopy

• What is the definition of a compound in microscopy?

  Composed of two or more parts
• What does magnification refer to in microscopy?

  The act of increasing the apparent size of an object
• What is the definition of resolution in microscopy?

  The ability to distinguish between two separate points.
• What does the term 'condense' mean?

  To make more dense or compact; reduce the volume or extent of something
• What does immersion mean in the context of microscopy?

  Placing under a liquid
• What does the term 'stain' refer to in microscopy?

  To color something
• What is the significance of the year 1674-1683 in microscopy?

  Anton van Leeuwenhoek developed powerful glass lenses and observed pond water
• What major contribution did Barthelemy Dumortier make to cell theory?

  He was the first to observe cell division in plants
• Who coined the term 'cells' and in what year?

  Robert Hooke in 1665
• What did Matthias Schleiden propose about plant tissues?

  All plant tissues were composed of cells
• What was Theodor Schwann's contribution to cell theory?

  He declared that all living things are composed of cells and cell products
• What did Robert Brown discover in 1833?


  The nucleus of a plant cell
• What did Luis Pasteur demonstrate in 1860 regarding spontaneous generation?


  He disproved the theory by showing bacteria only grow in sterile nutrient broth after exposure to air
• What are the major breakthroughs in the history of cell theory?


  • Anton van Leeuwenhoek: Observed microorganisms
  • Robert Hooke: Coined the term 'cells'
  • Matthias Schleiden: Proposed all plant tissues are composed of cells
  • Theodor Schwann: Declared all living things are composed of cells
  • Robert Brown: Discovered the nucleus
  • Luis Pasteur: Disproved spontaneous generation
• Why is it important to stain and section specimens in microscopy?


  Staining increases contrast and sectioning prevents distortion of the structure
• What is a wet mount slide?


  A slide where specimens are suspended in a liquid
• What is a squash slide?


  A wet mount that is gently pressed down to avoid damage
• What is a smear slide?


  A slide where the edge is used to create a thin, even coating of a sample
• How does staining work in microscopy?


  Stains increase contrast as different components within a cell take up stains to different degrees
• What is the purpose of differential staining?


  To distinguish between two types of organisms or different organelles within a tissue sample
• What happens to Gram-positive bacteria during the Gram staining technique?


  They retain the crystal violet stain and appear blue/purple
• What is the acid-fast technique used for?


  To distinguish between mycobacterium and other bacteria
• Why must specimens be thin when preparing a slide?


  To allow light to pass through for better visibility
• Why is the cover slip placed at an angle in a wet mount?


  To avoid trapping air bubbles under the cover slip
• What is the first step in using a microscope?


  Lower the stage and mount the slide using the clips
• How do you focus on a specimen using a microscope?


  Use the coarse focusing knob to bring the stage up and then the fine focusing knob for sharp focus
• What are the steps to prepare a wet mount slide?

  1. Place specimen in a liquid (e.g., water)
  2. Angle the cover slip to avoid air bubbles
  3. Observe under the microscope
• What are the steps to prepare a squash slide?

  1. Prepare a wet mount
  2. Use lens tissue to gently press down the cover slip
  3. Avoid damage by squashing between two slides
• What are the guidelines for making a good biological drawing?

  • Take up at least half a page
  • Use clear, continuous lines
  • No shading or coloring
  • Label lines must not cross
  • Use a ruler for label lines
  • Draw only what you see
• What equipment is needed to observe cheek cells?

  Microscope, slide, coverslip, cotton bud, methylene blue
• What is the total magnification of a light microscope with a 10x eyepiece and a 100x objective lens?

  $1000$
• What should you do after observing cheek cells under the microscope?


  Immerse the slide and coverslip in laboratory disinfectant
• What is the first step in observing onion cells?

  Place a drop of methylene blue stain onto the center of your slide
• What should you do after observing onion cells under the microscope?


  Immerse the slide and coverslip in laboratory disinfectant
• What is the purpose of using methylene blue in microscopy?


  To stain the cytoplasm and nucleus of cells
• What is the maximum light microscope magnification?


  $1500$
• Why is it important to use a sharp pencil for biological drawings?


  To ensure clear and precise lines
• Why should label lines not cross in a biological drawing?


  To avoid confusion and maintain clarity
• What is the significance of using a ruler for label lines in biological drawings?


  To ensure straight and neat label lines
• What is the purpose of using a continuous line in biological drawings?


  To create a clear representation of the specimen