Bio 15 Ch 3 Observing Microorganisms Through a Microscope
Key Terms:
Micrometer
Nanometer
objective lens
ocular lens
staining
fixed differential stain mordant: a chemical that fixes a dye in or
on a substance by combining with the dye to form an insoluble
compound
counterstain gram-positive gram-negative endospore
1. List the metric units of length in order, from meter to
nanometer. Be able to convert between units of length.
Meter m - Decimeter dm - Centimeter cm - Millimeter mm -
micrometer um
1 m = 10 dm, 1 dm = 10 cm, 1 cm = 10 mm, 1 mm = 1000 um
2. Discuss the relationship between contrast and staining in
microscopy
When preparing colorless specimen, the staining process by
adding color to the specimen, adds contrast between the
background and the organism.
3. What type of microscope do we use in the lab?
Light microscope uses visible light to observe the specimen.
Compound light microscope: uses a series of lens and visible light
to observe
