Microscopes

• What is the most common type of microscope used in early microbiology ventures?

  Light or optic microscope
• The light microscope uses light to visualize specimens.
• The light microscope focuses light onto the specimen using a lens
• What is the magnification range of the objective lens in a light microscope?

  4 to100 times
• What is the magnification factor of the eyepiece in a light microscope?

  10 or 15 times
• Some light microscopes can magnify an image up to 1,200 times its original size.
• Match the light microscope components with their functions:

  Stage ↔️ Supports the specimen

  Stage clips ↔️ Hold the specimen in place

  Diaphragm ↔️ Controls image contrast

  Slide adjustment knobs ↔️ Move the specimen
• What part of the light microscope holds the objectives?

  Nosepiece
• The coarse focus knob is used for large adjustments in focus.
• When using the slide adjustment knobs, the image in the microscope moves in the opposite direction
• What is the purpose of the fine focus knob?

  Refines the image
• Steps for focusing a light microscope

  1️⃣ Turn on the light source

  2️⃣ Secure the specimen on the stage

  3️⃣ Rotate the nosepiece to the smallest objective

  4️⃣ Use the coarse focus knob

  5️⃣ Use the fine focus knob
• After using the 100x objective, you should wipe the lens with lens paper.
• What are some common specimens studied with light microscopes?

  Bacteria, tissue slices, liquid samples
• What is the key difference between a standard and an inverted light microscope?

  Light source position
• Inverted light microscopes are often used to study tissue cultures
• Light microscopes are relatively inexpensive and easy to use.
• What is a limitation of light microscopes in terms of visualization?

  Limited resolution