Light microscopy

• What are the main parts of a light microscope?

  • Eyepiece
  • Objective lenses (e.g., x4, x10, x40)
  • Stage
  • Light source
  • Coarse and fine focus knobs
• How does the eyepiece of a light microscope function?

  The eyepiece is looked through to magnify the image.
• What is the purpose of the objective lenses in a light microscope?

  The objective lenses magnify the image at different levels.
• Why is it important to prepare specimens before viewing them under a microscope?

  Specimens need to be prepared to ensure clarity and visibility of details.
• What are the steps to prepare a slide for microscopy?

  1. Place a drop of water on the slide.
  2. Add the specimen to the water.
  3. Use a cover slip to avoid air bubbles.
  4. Press down gently to flatten the specimen.
• What should you do if you want to view a specimen at a higher magnification?

  You should switch to a higher objective lens and refocus.
• What is the formula for total magnification in microscopy?

  Total magnification = eyepiece magnification × objective lens magnification.
• If the eyepiece magnification is 10x and the objective lens magnification is 40x, what is the total magnification?

  Total magnification = $10 \times 40 =$$400$.
• How would you calculate the width of an image if the real size is 50 µm and the magnification is 100?

  Image size = magnification × real size = $100 \times 50 =$$5000 \text{ µm}$.
• What is standard form and why is it useful in scientific measurements?

  • Standard form expresses large or small numbers conveniently.
  • It simplifies calculations and comparisons.
  • It is useful for representing measurements in biology and other sciences.
• How would you express 0.0025 mm in standard form?

  0.0025 mm = $2.5 \times 10^{-3} \text{ mm}$.
• What are the key concepts related to magnification and image size in microscopy?

  • Magnification is how many times larger the image is than its real size.
  • Total magnification is calculated by multiplying the eyepiece and objective lens magnifications.
  • Image size can be calculated using the formula: $\text{Image size} =$$\text{Magnification} \times \text{Real size}$.