If you wish to change an immunofluorescence stain so

28.If you wish to change an immunofluorescence stain so it stains a different type of
microorganism than it did before, what would you do?
A. Use a different type of microscope.
B. Switch from epifluorescence to transmitted fluorescence.
C.Change the dye from a fluorescent to a non-fluorescent dye.
D.Change to a different type of fluorescent dye.
E.Use a different type of antibody.
29. Scanning electron microscopy is most often used to reveal __________.
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30. If you were given a specimen of an active, motile microorganism, which of the
following types of microscopy would be the most effective in visualizing the live
microbe?
31. The instrument that produces a bright image of the specimen against a dark
background is called a(n) __________ microscope.
32. A microscope that exposes specimens to ultraviolet and forms an image with the
resulting light emitted at a different wavelength is called a __________ microscope.
A. phase-contrast
B. dark-field
C. scanning electron
D. transmission electron
E. fluorescence
33. Which of the microscopes below form images in visible light?
34. What do phase-contrast and dark-field microscopes have in common?
35. Which of the microscopes below is usually good for use on unstained specimens?
36. Why do oil immersion objectives have higher numerical apertures than dry (non-oil)
lenses?
A. They are used closer to the specimen, therefore their lenses intercept light at
angles dray lenses would miss.
B. The oil used with the lenses prevents light from being refracted away from the
objectives as does occur with the dry lenses.
C. The oil used with the lenses increases the difference between the refractive
indices of the slide and the medium between the slide and the objective lens.
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D. A and B
E. B and C