Microscopes

• What does light microscopy use to magnify objects?

  Light and lenses
• What is the main advantage of electron microscopy over light microscopy?

  Higher resolution and detail
• What is the magnification of the eyepiece lens in a light microscope?

  10x
• What are the objective lenses used for in a light microscope?

  Provide different levels of magnification
• What is the function of the stage in a light microscope?

  Holds the slide in place
• Why is the light source important in a light microscope?

  It illuminates the sample for visibility
• What are the focus knobs used for in a light microscope?

  To sharpen the image
• What are the steps involved in sample preparation for light microscopy?

  1. Mounting: Place sample on a glass slide
  2. Fixation: Preserve structure to prevent decay
  3. Staining: Add dyes to enhance contrast
• How does the resolution of light microscopy compare to electron microscopy?

  Light microscopy has a lower resolution
• What is the maximum magnification of a light microscope?

  Up to 2000x
• What is the maximum magnification of an electron microscope?

  Up to 1,000,000x
• What are the advantages of light microscopy?

  Simple preparation and can view live samples
• What are the disadvantages of light microscopy?

  Limited resolution and requires stains
• What structures can be seen with light microscopes?

  Cell nuclei, cell walls, chloroplasts
• What structures can be seen with electron microscopes?

  Ribosomes, mitochondria, endoplasmic reticulum
• How do you prepare a sample for light microscopy?

  1. Mount the sample on a slide
  2. Optionally stain for contrast
  3. Observe under different magnifications
• What is magnification in microscopy?

  It makes small objects appear larger.
• What is the purpose of magnification?

  Enlarges the size of an object

  To view small detail that are otherwise invisible
• What is the formula for magnification?​

  $Magnification=$$\frac{Image\ Size}{Real\ Size}$
• If a cell's image size is 20mm and its actual size is 0.01mm, what is the magnification?

  2000x
• What does a high magnification with low resolving power result in?

  A blurry image despite the size increase
• What does λ represent in the resolving power formula?


  $\lambda=$$wavelength$
• What does 'image size' refer to in the magnification formula?

  The size of the image seen through the microscope.
• What does 'actual size' refer to in the magnification formula?

  The real size of the object.
• Why must image size and actual size be in the same units?

  To accurately calculate magnification.
• Calculate the magnification of an object if the image size is 10mm and the actual size is 1mm?

  $Magnification\ =$$\ 10$
• What is resolving power in microscopy?

  It shows the difference between closely spaced objects.
• What does a magnification of 5x mean?

  The image is 5 times bigger than the object.
• How is magnification typically expressed?


  x followed by a number
• If a microscope magnifies a cell to 200x, how much larger does it appear?

  200 times larger than its actual size
• What does resolving power determine in microscopy?

  The level of detail visible in an image
• How do magnification and resolving power differ?

  Magnification enlarges, resolving power clarifies