Discuss the ways in which light rays can be manipulated to increase resolution and/or contrast
What will be an ideal response?
Light rays can be manipulated to increase the resolution and contrast of a specimen in a variety of ways. In bright-field microscopes, immersion oil is used to capture light rays that would otherwise be refracted and lost; the result is an increase in the resolution of the image. Dark-field microscopes purposely scatter light rays in such a way as to improve the contrast of the specimen. Phase-contrast microscopes alter the wavelengths of light rays by splitting them into different paths then rejoining them, thereby increasing contrast. Finally, fluorescent microscopes use UV light, which produces increased resolution because of its shorter wavelength, and the fluorescent dyes that are used emit a variety of colors, increasing contrast.
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The _____ is associated with seasonal affective disorder (SAD)
a. pineal b. pituitary c. thyroid d. parathyroid e. thymus
Mutations in genes that affect __________ may cause morphological shifts in a lineage. Fill in the blank(s) with the appropriate word(s)
Cutaneous anthrax is
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