Microbiology Chapter 3 Test Bank

Which of the following is NOT equal to 1 mm? A) 0.001 m B) 10 6 nm C) 0.1 cm D) 100 μm E) 10-3 m - Answer: D 2) What structure does light pass through after leaving the condenser in a compound light microscope? A) Ocular lens B) Objective lens C) Specimen D) Illuminator - Answer: C 3) Which of the following pairs is mismatched? A) nigrosin — negative stain B) Methylene blue — simple stain C) Acidic dye — capsule stain D) Basic dye — negative stain E) Crystal violet — simple stain - Answer: D 4) Which of the following places the steps of the Gram stain in the correct order? 1-Alcohol-acetone 2-Crystal violet 3-Safranin 4-Iodine A) 1-2-3-4 B) 2-1-4-3 C) 2-4-1-3 D) 4-3-2-1 E) 1-3-2-4 - Answer: C 5) Which of the following pairs is mismatched? A) alcohol-acetone — decolorizer B) crystal violet — basic dye C) Safranin — acid dye D) Iodine — mordant E) Carbol fuchsin — basic dye - Answer: C 6) Which of the following is NOT true regarding the acid-fast stain? A) It is used to identify members of the genus Mycobacterium. B) Acid-fast cells retain the primary dye after treatment with acid-alcohol. C) If cells are acid-fast, they are gram-negative. D) Acid-fast cells appear red in a completed acid-fast stain. E) Non-acid-fast microbes appear blue in a completed acid-fast stain. - Answer: C 7) The purpose of a mordant in the Gram stain is to A) Remove the simple stain. B) Make the bacterial cells larger. C) Make the flagella visible. D) Prevent the crystal violet from leaving the cells. E) Make gram-negative cells visible. - Answer: D 8) Which of the following places the steps in the correct sequence? 1-Staining 2-Making a smear 3-Fixing A) 1-2-3 B) 3-2-1 C) 2-3-1 D) 1-3-2 E) The order is unimportant. - Answer: C