front 1 The _______ of a compound light microscope focuses light from the light source on the specimen. | back 1 Condenser lens OR condenser |
front 2 Which of the following is the most convenient and appropriate unit for expressing the size of an average bacterial cell? | back 2 Micrometer |
front 3 All of the following are visible through a compound light microscope except____. | back 3 0.02-AUM ribosome |
front 4 Bacterial motility and flagellar movement can readily be viewed using transmission electron microscopy. | back 4 False |
front 5 A____________ is equal to 0.000001m. | back 5 micrometer |
front 6 Acid-fast Mycobacteria differ from non-acid-fast bacteria by the presence of ____. In the decolorizing step of the acid -fast stain, which reagent is used? | back 6 carbol fuchsin waxy material in their cell wall |
front 7 When stained, bacteria in the genus Mycobacterium are ____. When using a 10x ocular lens and a 40x objective, the total magnification achieved is | back 7 acid-fast 400x |
front 8 Which of the following is not a modification of a compound microscope? | back 8 electron microscope |
front 9 Flagella are too ________ to be seen with the light microscope without adding a mordant. | back 9 small or thin |
front 10 Immersion oil acts to decrease refraction of light rays and thus increase resolution. | back 10 True |
front 11 In the Gram stain, if the decolorizing step is deleted, gram-negative cells will appear _______ at the completion of the staining procedure. | back 11 Purple |
front 12 Magnification is the quality of the microscope that allows on to distinguish between two points that are very close together. | back 12 False |
front 13 Place these structures of the compound light microscope in order that light passes through them on the way to the observer's eyes: (1) condenser,(2)ocular lens, (3) illuminator, (4)specimen, (5) objective lens. | back 13 3-1-4-5-2
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front 14 Bacterial smears must be heat-fixed before all staining procedures. | back 14 False |
front 15 The ______ charge of a basic dye adheres to the ______ charge of bacterial cell surfaces. | back 15 positive;negative |
front 16 The _____ is the part of the microscope that controls the amount of the light entering the condenser. | back 16 diaphragm |
front 17 The Gram stain is important in medical microbiology because the results help physicians select appropriate antibiotics for treatment. | back 17 True |
front 18 Which of the following kinds of microscopy would be most appropriate for viewing the shape and arrangement of pili or fimbriae on the surface of the bacterial cell? | back 18 scanning electron microscopy |
front 19 Which of the following types of microscopy is most useful for viewing the internal structures of unstained specimens? | back 19 Phase-contrast |
front 20 You are viewing a sputum smear that has been stained with an acid-fast stain. On this smear you see 5-Aum-long red cells. You can conclude that _______. | back 20 there are acid-fast bacteria in the specimen |