NUR 1022C Lab Quiz 1 (already solved and graded) Latest Fall 2021

NUR 1022C Lab Quiz 1 Question 1 The of the microscope holds and allows selection of the objective lenses. ocular stage nosepiec e condens er Question 2 Humans can see objects as small as 0.1 mm. Leeuwenhoek's best microscope could magnify objects to 300X. Which of the following would be invisible using Leeuwenhoek's microscope? Poliovirus, 30 nm Pandora virus, 0.5 mm X 1 mm Red blood cell, 8 μm Escherichia coli, 1 μm X 4 μm Question 3 Which of the following parts of the microscope magnifies the specimen to produce the virtual image of the specimen? Body Condenser Objective lens Ocular lens Question 4 A microbiology student with a visual disability is viewing a sample of Bacillus endospores in a phase contrast microscope that is linked to an iPad. By "stretching" the image on the iPad screen, the student can increase the apparent size of the endospores. How does this manipulation affect resolution and contrast? (No software is being used to alter the image!) Both magnification and resolution increase; contrast is unchanged. Resolution and magnification will decrease because the screen is not as good as the human eye. Contrast will improve because the microscope is phase-contrast. Only the magnification can be increased; resolution and contrast are unchanged. Question 5Which of the following parts of a microscope magnifies the specimen to produce a real image of the specimen? Ocular lens Objective lens Nosepiece Condenser Body Question 6 The bending of light rays as they pass from one medium to another is called refraction. True False Question 7 Which type of microscope achieves the greatest resolution and highest magnification? Dark-field Electron Bright-field Fluorescenc e Phasecontrast Question 8 The type of microscopy in which you would observe brightly illuminated specimens against a black background is . fluorescence phasecontrast dark-field electron confocal Question 9 A differential interference contrast microscope uses dyes to give colored, threedimensional images. True False Question 10 Which type of microscope shows cells against a white background?Confocal Fluorescenc e Phasecontrast Bright-field Electron Question 11 All of the following pertain to the fluorescence microscope except it is used to diagnose certain infections. it uses electrons to produce a specimen image. it is a type of compound microscope. it requires the use of dyes like acridine or fluorescein. it requires an ultraviolet radiation source. Question 12 Which type of microscope bombards a whole, metal-coated specimen with electrons moving back and forth over it? Fluorescence Transmission electron Phase-contrast Scanning electron Differential interference contrast Question 13 Which term is not used to describe bacterial cell shape? Bacillus Spiroche te Vibrio Tetrad Coccus Question 14 The term diplococcus refers to an irregular cluster of spherical bacterial cells. True FalseQuestion 15 An irregular cluster of spherical bacterial cells is termed . streptococcus staphylospirill um staphylobacillu s staphylococcu s streptobacillus Question 16 When bacilli in a chain fold back upon each other like a hinge, this cellular arrangement is termed a . staph palisa de tetrad strep sarcin a Question 17 A chain of rod-shaped cells would be called a . streptococcu s Staphylobacil lus streptobacillu s staphylococc us palisade Question 18 Following a properly-performed Gram stain, gram-positive bacteria will appear as pink or red cells. True False Question 19 A microbiologist makes a fixed smear of bacterial cells and stains it with methylene blue. All cells appear blue under the oil immersion lens. This is an example of . capsulestaining the acid-fast stain simple staining negative staining using an acidic dye Question 20 The purpose of staining cells on a microscope slide is to . secure them to the slide observe motility enlarge the cells kill them add contrast to see them better Question 21 The cell envelope of gram-positive bacteria has two layers: a thick cell wall and the cell membrane. True False Question 22 Basic dyes are dyes such as India ink and nigrosin. repelled by cells. anionic. used in negative staining. attracted to the acidic surface of bacterial cells. Question 23 If the bacterial cells were viewed immediately after crystal violet was applied during the Gram stain procedure, gram-positive cells would be purple but gram-negative cells would be colorless. True False Question 24 Which is the correct order for the application of reagents in the Gram stain? Crystal violet, safranin, iodine,alcohol/acetone Crystal violet, alcohol/acetone, iodine, safranin Safranin, crystal violet, alcohol/acetone, iodine Iodine, safranin, crystal violet, alcohol/acetone Crystal violet, iodine, alcohol/acetone, safranin Question 25 The Gram staining procedure is best described as a staining technique. differenti al selective simple negative