5What is meant by light rays being divergent? It is heading upwards It is coming together to a focused beam It is spreading out C. it is spreading out

66All of the following are common to both the Gram stain and the acid-fast stain EXCEPT A) primary stain.B) counterstain.C) a decolorizing agent and a counterstain.D) a decolorizing agent.E) a chemical mordant.E) a chemical mordant.

Cationic chromophores such as methylene blue ionically bond to __________________ charged chemicals such as DNA and proteins.

47The primary goal of modern taxonomists is to A) establish unique identifiers for each species.B) understand the phylogenetic relationships between organisms.C) have a complete inventory of all living things.D) determine what defines a species.E) There is no consensus among taxonomists regarding their primary goal.B) understand the phylogenetic relationships between organisms.

The Sekonic L-398A Studio Deluxe III 70th Anniverary Edition comes with: Burgundy with Rose Gold in color, Special Display Box, "70th Anniversary" on front panel, Special Leather Case and Strap. Small compact and easy to use the Sekonic L-398A incorporates a battery-less amorphous photocell which enables you to take accurate ambient light readings anywhere anytime.

A) the refraction of radiation as it passes through a lensB) the wavelength of a radiation sourceC) the numerical aperture of a lensD) the length of an objective lensE) the thickness of a microscopic specimen

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178Negative stains such as eosin are also called __________________. a. capsule stains b. endospore stains c. simple stains d. acid-fast stainsa. capsule stains

23All of the following are types of light microscopes EXCEPT A) confocal.B) bright-field.C) scanning tunneling.D) phase-contrast.E) fluorescent.C) scanning tunneling.

Light rays that pass through the edge of a curved lens will be refracted more than those that pass through the center. T/F

68A virologist wants to observe the surface features of virus particles she is studying. Which of the following microscopes would NOT be useful for her observations? A) transmission electronB) scanning electronC) atomic forceD) differential interference contrastE) scanning tunnelingD) differential interference contrast

76The process of immobilizing organisms on a glass slide through the application of eitherheat or chemicals is _______.fixation

4What is the role of the ocular lens? To adjust the wavelength of light To do the bulk of the magnification To focus the light to a high intensity in a small area To recreate the image in the viewer’s eye D. To recreate the image in the viewer’s eye

24Which of the following microscopes produces the highest resolution images? A) scanning electronB) fluorescentC) differential interferenceD) atomic forceE) dark-fieldD) atomic force

39Heat is used to drive the stain into cells in the ________ staining procedure(s). A) capsule stainB) acid-fast stainC) Gram stainD) endospore stainE) both acid-fast and endospore stainsE) both acid-fast and endospore stains

107Place the following steps in the correct sequence: 1. staining 2. making a smear 3. fixing 1-2-3 3-2-1 2-3-1 2-1-3 1-3-2 C) 2-3-1

87Light rays that pass through the edge of a curved lens will be refracted more than those that pass through the center. T/FTrue

You volunteer to help the student with his fixation technique and in choosing a proper stain for the project he is working on. After watching and helping the student correct any problems with his fixation technique, you now need to determine which stains to use. The single criterion for the project is to be able to determine cell shape and size in a pure broth culture after some treatments. No differentiation between cell types is required (i.e., Gram-positive or Gram-negative), so you want to convince the student that a simple stain would be his best option. The charged dyes used in simple staining will penetrate the bacterial cell and will be retained after rinsing the slide with water to remove surplus dye. Which staining procedure would be best to use to stain the slides required for this student’s project? Why?

8How are negative stains different from other types of stains? They stain more than one type of specimen. They stain the desired structure or specimen black. They stain the background, leaving the cells colorless. C. They stain the background, leaving the cells colorless.

37Which of the following is NOT associated with an electron microscope? A) a vacuumB) a fluorescent screenC) an electron beamD) magnetic fieldsE) a prismE) a prism

163The fluorescent stain is used to reveal the presence of negatively charged capsules. T/FFalse (the negative stain is used)

17Viruses are not included in the taxonomic scheme proposed by Carl Woese because they lack _____. A) proteins.B) ribosomal RNA.C) cytoplasm.D) genetic material.E) lipid membranes.B) ribosomal RNA.

172Resolution is best described as the __________________. a. ability to view something that is small b. ability to magnify a specimen c. ability to distinguish between two adjacent objects d. difference between two waves of electromagnetic radiationc. ability to distinguish between two adjacent objects

161Gomori methenamine silver stain is used to screen for the presence of fungi and the location of carbohydrates in tissues. T/FTrue

You are shown a micrograph from a light microscope in which the specimens appear bright compared to the background. The micrograph is probably from a(n) ________ microscope.

159Which of the following is NOT a characteristic of a genus name? A) It is one of two names used to identify an organism.B) It is written before the specific epithet.C) It is always capitalized.D) It is usually an adjective.E) It is either underlined or in italics.D) It is usually an adjective (it's a noun)

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1. Cell wall of Gram-negative cells is broken down; Gram-positive cells remain intact 2. All cells are stained purple 3. Dye molecules are rendered insoluble in presence of mordant; dye is rinsed away 4. Clear cells are stained a red or pink whereas the color of other cells remains unchanged

32Which of the following is NOT a characteristic of a genus name? A) It is one of two names used to identify an organism.B) It is written before the specific epithet.C) It is always capitalized.D) It is usually an adjective.E) It is either underlined or in italics.D) It is usually an adjective (it is a noun)

A) Animalia and Plantae.B) Fungi and Protista.C) Prokaryotae and Protista.D) Animalia and Prokaryotae.E) Protista and Plantae.

58Viruses are generally measured in _______. A) millimeters.B) centimeters.C) nanometers.D) micrometers.E) decimeters.C) nanometers.

65Carbolfuchsin is the ________ in the acid-fast stain. A) fixing reagentB) primary stainC) counterstainD) decolorizerE) mordantB) primary stain

Endospores cannot be stained by normal staining procedures because their cell walls are practically impermeable to all chemicals. T/F

A) establish unique identifiers for each species.B) understand the phylogenetic relationships between organisms.C) have a complete inventory of all living things.D) determine what defines a species.E) There is no consensus among taxonomists regarding their primary goal.

153What kind of dyes are used in negative staining, and why?Acidic dyes, because they are repulsed by the negatively charged cell

21Which of the following is NOT equal to 50 millimeters? 0.05 meters 5,000,000 nanometers 5 centimeters 50,000 micrometers 5,000,000 nanometers

The positively charged methylene blue will be attracted to the negatively charged components of the cell wall and will be retained.

46Bacteria and many other microbes do not ________ and therefore do not fit Linneaus' definition species. A) have cytoplasmic membranesB) have nucleiC) exchange genetic materialD) reproduce sexuallyE) reproduce asexuallyreproduce sexually

106The purpose of mordant in Gram staining is: to remove the simple stain to make the bacterial cell larger to make the flagella visible to prevent the crystal violet from leaving the cell none of the above D) to prevent the crystal violet from leaving the cell

A) changes the pH and therefore the structure of DNA.B) is an effective fixing agent for nucleic acids.C) forms ionic bonds with DNA.D) makes DNA electron dense.E) covalently bonds with DNA.

64Which of the following phenomena produces magnification? A) the refraction of radiation as it passes through a lensB) the wavelength of a radiation sourceC) the numerical aperture of a lensD) the length of an objective lensE) the thickness of a microscopic specimenA) the refraction of radiation as it passes through a lens

20If a microbiologist omitted the decolorizer from a Gram-stained smear, which of the following would happen? All cells in the smear would be purple. Gram-positive cells would be pink and Gram-negative cells would be purple. All cells in the smear would be pink. All cells in the smear would be colorless. All cells in the smear would be purple

14Put the following descriptions in order for the staining reactions in the cells of a bacterial smear during the Gram staining procedure: 1. Cell wall of Gram-negative cells is broken down; Gram-positive cells remain intact 2. All cells are stained purple 3. Dye molecules are rendered insoluble in presence of mordant; dye is rinsed away 4. Clear cells are stained a red or pink whereas the color of other cells remains unchanged1. All cells are stained purple 2. Dye molecules are rendered insoluble in presence of mordant; dye is rinsed away 3. Cell wall of Gram-negative cells is broken down; Gram-positive cells remain intact 4. Clear cells are stained a red or pink whereas the color of other cells remains unchanged

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25A thin film of microbes on a slide is a _______. A) agglutination.B) fixation.C) a Gram reaction.D) a smear.E) a biopsy.D) a smear.

160Endospores cannot be stained by normal staining procedures because their cell walls are practically impermeable to all chemicals. T/FTrue

55A sample from a patient is prepared using the Gomori methenamine silver stain. What type of microbe is suspected of being present? A) parasitic worm larvaB) virusC) bacteriaD) protozoal parasiteE) fungusE) fungus

184Which of the following is NOT a characteristic of viruses? They are acellular. They are composed of genetic material and protein. They are visible with a light microscope. They are smaller than prokaryotic cells. They are obligatory parasites. C. They are visible with a light microscope (they are visible with an electron microscope)

A) The sample is placed in a vacuum.B) Stains can be applied to improve contrast.C) Electrons are the source of visualization.D) Thin segments must be used.E) Glass lenses are used.

110The appearance of Gram negative bacteria after completing the Gram stain is: purple red colorless brown blue B) red

2Why is a specimen smaller than 200 nm not visible with a light microscope? The lenses only go to 100 X magnification power. Visible light is only good at wavelengths below 390 nm. Anything smaller than 200 nm cannot interact with visible light. It is too easy to lose on the stage. C. Anything smaller than 200 nm cannot interact with visible light.

141Which electron microscope generates a beam of electrons that produce an image on a fluorescent screen?Transmission electron microscope

31A cell's G + C ratio is associated with which of the following classification methods? A) physical characteristicsB) biochemical testsC) analysis of nucleic acidsD) phage typingE) serological testsC) analysis of nucleic acids

183Cationic chromophores such as methylene blue ionically bond to __________________ charged chemicals such as DNA and proteins.negatively

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Immersion oil __________________ (increases/decreases) the numerical aperture, which __________________ (increases/ decreases) resolution because __________________ (more/fewer) light rays are involved.

7Which phenomena produces magnification? the wavelength of a radiation source the numerical aperture of a lens the length of an objective lens the refraction of radiation as it passes through a lens the thickness of a microscopic specimen D. the refraction of radiation as it passes through a lens

90Acid-fast cells such as Mycobacterium lose the color of the primary stain in the presence of hydrochloric acid. T/FFalse (hydrochloric acid removes color from non-acid fast cells and the background, but not the acid fast cells)

A) It is one of two names used to identify an organism.B) It is written before the specific epithet.C) It is always capitalized.D) It is usually an adjective.E) It is either underlined or in italics.

62The limits of resolution of atomic force microscopes is in the range of _______. A) millimeters (mm).B) centimeters (cm).C) meters (m).D) nanometers (nm).E) micrometers (μm).D) nanometers (nm).

A student from one of the research labs is having trouble preparing a slide for examination and photographing. The bacterial slide that he has brought to you was prepared using a commercially purchased stain. He has asked for your help in determining what he is doing wrong so that he can change the lab protocols and continue on with his project. After examining the slide under oil immersion, you determine that no bacteria are present even though the student is able to show you the culture he used to make that slide that has visible growth in the liquid medium.Which of the following statements does NOT explain the fact that there are no bacteria present on the student’s slide?

A) It is one of two names used to identify an organism.B) It is written before the specific epithet.C) It is always capitalized.D) It is usually an adjective.E) It is either underlined or in italics.

A) It allows light to travel at a uniform speed on its way to the lens.B) It decreases the working distance.C) It increases the angle of refraction of the light.D) It increases numerical aperture and maintains a uniform light speed.E) It increases the numerical aperture.

30The ability of a lens to gather light is referred to as its _______. A) refraction.B) contrast.C) magnification.D) resolution.E) numerical aperture.E) numerical aperture.

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86Gram staining of bacteria provides all the physical characterization necessary to identify bacterial species. T/FFalse (differentiates based on cell walls only)

44The ________ stain is one in which eosin is used. A) electron microscopyB) flagellarC) endosporeD) acid-fastE) negativeE) negative

143Which microscopes use a magnetic field within a vacuum tube to manipulate a beam of electrons called primary electrons?Electron microscopes

50The most appropriate unit of measurement for intact archaea is the _______. A) nanometer (nm).B) centimeter (cm).C) meter (m).D) millimeter (mm).E) micrometer (μm).E) micrometer (μm).

43Methylene blue can be used to stain DNA because it A) changes the pH and therefore the structure of DNA.B) is an effective fixing agent for nucleic acids.C) forms ionic bonds with DNA.D) makes DNA electron dense.E) covalently bonds with DNA.C) forms ionic bonds with DNA.

40Which of the following classification methods relies on the morphology of organisms? A) analysis of nucleic acidsB) physical (phenotypic) characteristicsC) biochemical testsD) serological testsE) phage typingB) physical (phenotypic) characteristics

15Nigrosin staining-not safranin staining-of Klebsiella pneumoniae will allow for the visualization of the cell shape and the determination of the presence of a capsule. T/FTrue

10Following an endospore stain, how does one distinguish endospores from vegetative cells? Vegetative cells are pink, endospores are green. Vegetative cells are pink, endospores are purple. Vegetative cells are green, endospores are pink. Vegetative cells are purple, endospores are pink. A. Vegetative cells are pink, endospores are green.

A sample from a patient is prepared using the Gomori methenamine silver stain. What type of microbe is suspected of being present?

A) work best in low pH environments.B) are negatively charged and work best at low pH.C) are lipid soluble.D) are used for staining negatively charged molecular structures.E) are negatively charged.

175Which of the following is different between light microscopy and transmission electron microscopy? a. magnification b. resolution c. wavelengths d. all of the aboved. all of the above

22The Gram stain works because of differences in the ________ of bacteria. A) antigensB) capsulesC) cell wallsD) genetic characteristicsE) cell membranesC) cell walls

False (pararosaniline and carbolfuchsin are used in flagella stains, heavy metals are used for electron microscope stains)

56In the Gram stain procedure, iodine serves as a _______. A) mordant.B) primary stain.C) fixative.D) counterstain.E) decolorizing agent.A) mordant.

Which microscope rapidly focuses the electrons back and forth across a specimen’s surface, which has previously been coated with a metal such as platinum or gold?

A) transmission electronB) scanning electronC) atomic forceD) differential interference contrastE) scanning tunneling

116In negative staining the negatively charged dye molecules bind to the negatively charged part of the bacteria. T/FFalse (they repel the bacteria)

If a microbiology lab student left the safranin out of the Gram stain procedure, what would be the result? A) All cells would be pink.B) Gram-positive cells would be pink and Gram-negative cells would be purple.C) All cells would be purple.D) Gram-positive cells would be colorless and Gram-negative cells would be pink.E) Gram-positive cells would be purple and Gram-negative cells would be colorless.

27One-thousandth of a meter is a _______. A) nanometer (nm).B) yard.C) millimeter (mm).D) micrometer (μm).E) centimeter (cm).C) millimeter (mm)

35If a microbiology lab student left the safranin out of the Gram stain procedure, what would be the result? A) All cells would be pink.B) Gram-positive cells would be pink and Gram-negative cells would be purple.C) All cells would be purple.D) Gram-positive cells would be colorless and Gram-negative cells would be pink.E) Gram-positive cells would be purple and Gram-negative cells would be colorless.E) Gram-positive cells would be purple and Gram-negative cells would be colorless.

108This microscope is used to observe a specien that emits light when illuminated with a UV light. compound light microscope phase contrast microscope dark field microscope fluorescence microscope electron microscope D) fluorescence microscope

Molecules that absorb energy from invisible radiation (such as ultraviolet light) and then radiate the energy back as a longer, visible wavelength are said to be _______.

42The ________ stain makes use of malachite green. A) negativeB) acid-fastC) endosporeD) electron microscopyE) flagellarC) endospore

174Which of the following factors is important in making an image appear larger? a. thickness of the lens b. curvature of the lens c. speed of the light passing through the lens d. all of the aboved. all of the above

A structure that appears in a transmission electron micrograph but is NOT actually present in the specimen is known as a(n) _______.

49Which of the following are magnifying lenses? A) dark-field stopsB) objectivesC) condensersD) ocularsE) both objectives and the ocularsE) both objectives and the oculars

137Molecules that absorb energy from invisible radiation (such as ultraviolet light) and then radiate the energy back as a longer, visible wavelength are said to be _______.Fluorescent

53A structure that appears in a transmission electron micrograph but is NOT actually present in the specimen is known as a(n) _______. A) artifact. B) antigen. C) mordant. D) biofilm. E) refraction.A) artifact.

67The size of a pork tapeworm is generally described in terms of _______. A) millimeters (mm.)B) nanometers (nm).C) meters (m).D) micrometers (μm).E) decimeters (dc).C) meters (m).

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51A sample is prepared using osmium tetroxide as a stain. This sample has been prepared for a(n) ________ microscope. A) electronB) fluorescenceC) differential interference contrastD) atomic forceE) phase-contrastA) electron

12A student from one of the research labs is having trouble preparing a slide for examination and photographing. The bacterial slide that he has brought to you was prepared using a commercially purchased stain. He has asked for your help in determining what he is doing wrong so that he can change the lab protocols and continue on with his project. After examining the slide under oil immersion, you determine that no bacteria are present even though the student is able to show you the culture he used to make that slide that has visible growth in the liquid medium.Which of the following statements does NOT explain the fact that there are no bacteria present on the student’s slide? By not allowing a glass slide to completely air dry before heat fixation, the flame will cause the surrounding water to boil and this will damage the bacterial cell. Overheating during the fixation step boiled the water within the bacterial cells and resulted in the cells bursting. Insufficient heating of the slide did not drive out the thin layer of water and this resulted in minimal bonding between the bacteria and the glass slide. Rinsing with alcohol during the washing step stripped the bacteria off the glass slide. Rinsing with alcohol during the washing step stripped the bacteria off the glass slide.

63Acidic dyes A) work best in low pH environments.B) are negatively charged and work best at low pH.C) are lipid soluble.D) are used for staining negatively charged molecular structures.E) are negatively charged.B) are negatively charged and work best at low pH.

164The stains used for electron microscopes include pararosaniline and carbolfuchsin. T/FFalse (pararosaniline and carbolfuchsin are used in flagella stains, heavy metals are used for electron microscope stains)

Which microscopes use a magnetic field within a vacuum tube to manipulate a beam of electrons called primary electrons?

60You are shown a micrograph from a light microscope in which the specimens appear bright compared to the background. The micrograph is probably from a(n) ________ microscope. A) bright-fieldB) dark-fieldC) NomarskiD) atomic forceE) phase-contrastB) dark-field

114Acid fast bacteria have mycolic acid in their cell wall that makes them more permeable to stains and chemicals. T/FFalse (makes them less permeable)

167The organization of organisms on the basis of mutual similarities into non-overlapping groups is called taxa. T/FTrue

What is it called if a scientist were to use multiple lens to magnify an image millions of time, but the image is blurry and faint?

Gomori methenamine silver stain is used to screen for the presence of fungi and the location of carbohydrates in tissues. T/F

1. All cells are stained purple 2. Dye molecules are rendered insoluble in presence of mordant; dye is rinsed away 3. Cell wall of Gram-negative cells is broken down; Gram-positive cells remain intact 4. Clear cells are stained a red or pink whereas the color of other cells remains unchanged

18Plaques are associated with which of the following methods of laboratory identification of microorganisms? biochemical tests phage typing serological tests nucleic acid analysis B). phage typing (bacteriophage is a virus that inserts its DNA into a bacterium)

The rules of naming organisms are called A) classification.B) taxonomy.C) binomials.D) nomenclature.E) identification.

61Which of the following statements about transmission electron microscopy is FALSE? A) The sample is placed in a vacuum.B) Stains can be applied to improve contrast.C) Electrons are the source of visualization.D) Thin segments must be used.E) Glass lenses are used.E) Glass lenses are used.

181Immersion oil __________________ (increases/decreases) the numerical aperture, which __________________ (increases/ decreases) resolution because __________________ (more/fewer) light rays are involved.increase; increase; more

144Which microscope rapidly focuses the electrons back and forth across a specimen’s surface, which has previously been coated with a metal such as platinum or gold?Scanning electron microscope

34In Gram staining, ethanol-acetone is used as a: A) mordant.B) counterstain.C) drying agent.D) decolorizing agent.E) primary stain.D) decolorizing agent.

11What is the fundamental purpose of staining in light microscopy? To see the specimen without the aid of a microscope To make the specimen appear larger in the microscope To kill the specimen To increase the contrast and visibility of the specimen D. To increase the contrast and visibility of the specimen

171A nanometer is __________________ than a micrometer. a. 10 times larger b. 10 times smaller c. 1000 times larger d. 1000 times smallerd. 1000 times smaller

45Which of the following is an INCORRECT pairing? A) magnification; refraction of radiationB) simple microscope; LeeuwenhoekC) contrast; staining techniquesD) electron beams; shorter wavelengthE) numerical aperture; curved glassE) numerical aperture; curved glass

52Carl Woese proposed the concept of the domain based on differences of which cellular molecule? A) membrane lipidsB) transfer RNAC) DNAD) proteinsE) ribosomal RNAE) ribosomal RNA

122What is it called if a scientist were to use multiple lens to magnify an image millions of time, but the image is blurry and faint?Empty magnification

109The appearance of Gram positive bacteria after adding the counter stain in the Gram stain: violet red colorless brown none of the above A) violet

13You volunteer to help the student with his fixation technique and in choosing a proper stain for the project he is working on. After watching and helping the student correct any problems with his fixation technique, you now need to determine which stains to use. The single criterion for the project is to be able to determine cell shape and size in a pure broth culture after some treatments. No differentiation between cell types is required (i.e., Gram-positive or Gram-negative), so you want to convince the student that a simple stain would be his best option. The charged dyes used in simple staining will penetrate the bacterial cell and will be retained after rinsing the slide with water to remove surplus dye. Which staining procedure would be best to use to stain the slides required for this student’s project? Why? Malachite green and heat will colorize the cell for easier visualization and is a simple process. Using crystal violet followed by a rinse and Gram’s iodine will stain the cells a dark blue with large crystals. The positively charged methylene blue will be attracted to the negatively charged components of the cell wall and will be retained. An acidic stain such as nigrosin will stain the cells a dark black coloration for easier viewing under the microscope. The positively charged methylene blue will be attracted to the negatively charged components of the cell wall and will be retained.

82The three domains proposed by Carl Woese are the Archaea, the Eukarya, and the Protista. T/FFalse (he proposed eukarya, bacteria, and archaea)

Which of the following is NOT associated with an electron microscope? A) a vacuumB) a fluorescent screenC) an electron beamD) magnetic fieldsE) a prism

28Tannic acid is a mordant (chemical fixative) used in the ________ stain. A) endosporeB) acid-fastC) flagellarD) electron microscopyE) negativeC) flagellar

Put the following descriptions in order for the staining reactions in the cells of a bacterial smear during the Gram staining procedure:

105Which of the following pairs are mismatched? Gram-negative bacteria; negative stain iodine; mordant alcohol; decolorizer methylene blue; simple stain A) Gram-negative bacteria; negative stain

1What is the role of lenses in microscopy? Lenses increase the contrast to determine structural differences in stained specimens. Lenses are only used to magnify specimens that are smaller than whole red blood cells. Lenses focus either light or electrons to create a magnified image of a specimen. C. Lenses focus either light or electrons to create a magnified image of a specimen.

All of the following are types of light microscopes EXCEPT A) confocal.B) bright-field.C) scanning tunneling.D) phase-contrast.E) fluorescent.

142Can transmission electron microscopes be used to examine living things?No (because of the vacuum and slicing of specimens)

All of the following are types of light microscopes EXCEPT A) confocal.B) bright-field.C) scanning tunneling.D) phase-contrast.E) fluorescent.

A) Modern microscopes have lenses with smaller numerical apertures.B) Modern microscopes are compound and have fivefold better resolution.C) Modern microscopes have a fivefold better resolution.D) Modern lenses are made of prisms.E) Modern microscopes are compound instead of simple.

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29Species and strains of microbes can be distinguished from one another phenotypically using _______. A) serological tests.B) G + C content.C) electron microscopy.D) Gram-stain reactions.E) ribosomal RNA analysisA) serological tests.

A) primary stain.B) counterstain.C) a decolorizing agent and a counterstain.D) a decolorizing agent.E) a chemical mordant.

3What happens to the light rays when they hit the specimen? They are reflected, refracted, or absorbed by the specimen. They are diverted to the ocular lens. They are absorbed by the stage. They are focused into a small area towards the objective lens. A. They are reflected, refracted, or absorbed by the specimen.

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38All of the following are types of light microscopes EXCEPT A) confocal.B) bright-field.C) scanning tunneling.D) phase-contrast.E) fluorescent.C) scanning tunneling (probe microscope)

48Tungsten is a reagent used in the _______. A) acid-fast stain.B) negative stain.C) electron microscopy stain.D) flagellar stain.E) endospore stain.C) electron microscopy stain.

176Which of the following types of microscopes produces a three-dimensional image with a shadowed appearance? a. simple microscope b. differential interference contrast microscope c. fluorescence microscope d. transmission electron microscopeb. differential interference contrast microscope

41The kingdoms included in the Linnaeus system of classification are _______ and _______. A) Animalia and Plantae.B) Fungi and Protista.C) Prokaryotae and Protista.D) Animalia and Prokaryotae.E) Protista and Plantae.A) Animalia and Plantae.

179In the binomial system of nomenclature, which term is always written in lowercase letters? a. kingdom b. domain c. genus d. specific epithetd. specific epithet

85Scanning tunneling microscopes map the topography of a specimen by detecting the deflection of the probe tip. T/FFalse (an atomic force microscope maps the topography of a specimen by detecting the deflection of the probe tip)

158Why must air be evacuated from the column of an electron microscope?Air would absorb electrons so there would be no radiation to produce an image

57Why are modern light microscopes better than the ones Leeuwenhoek used? A) Modern microscopes have lenses with smaller numerical apertures.B) Modern microscopes are compound and have fivefold better resolution.C) Modern microscopes have a fivefold better resolution.D) Modern lenses are made of prisms.E) Modern microscopes are compound instead of simple.B) Modern microscopes are compound and have fivefold better resolution.

113Bacterial smears are heat fixed before staining to make their cell wall more permeable. T/FFalse (it kills the specimen and makes them stick to the slide)

A virologist wants to observe the surface features of virus particles she is studying. Which of the following microscopes would NOT be useful for her observations?

26The rules of naming organisms are called A) classification.B) taxonomy.C) binomials.D) nomenclature.E) identification.D) nomenclature.

16Methylene blue can be used to stain DNA because it changes the pH and therefore the structure of DNA. makes DNA electron dense. is an effective fixing agent for nucleic acids. forms ionic bonds with DNA. covalently bonds with DNA. D. forms ionic bonds with DNA.

19The reagents crystal violet, iodine, and safranin are all associated with which of the following staining procedures? the endospore stain the flagella stain the acid-fast stain the Gram stain D. The Gram stain

166Biologists classify organisms for the following reasons EXCEPT to bring a sense of order and organization to the variety and diversity of living things to enhance communication to further the field of microbiology to make predictions about the structure and function of similar organisms to uncover and understand potential evolutionary connections. C) to further the field of microbiology

6In a typical bright-field microscope, at which point does magnification begin? The objective lens The lamp The ocular lens The stage The condenser lens The objective lens (magnification begins from bottom to top)

36Safranin dye is used as the counterstain in ________ stain(s). A) the flagellarB) the acid-fastC) the GramD) the endosporeE) both the Gram and the endosporeE) both the Gram and the endospore

A) analysis of nucleic acidsB) physical (phenotypic) characteristicsC) biochemical testsD) serological testsE) phage typing

33The microscope preferred for viewing living specimens is the ________ microscope. A) scanning tunnelingB) bright-fieldC) scanning electronD) phase-contrastE) transmission electronD) phase-contrast

54If you were trying to visualize flagella without staining, which microscope would you use? A) fluorescentB) phase-contrastC) confocalD) bright-fieldE) dark-fieldB) phase-contrast

Nigrosin staining-not safranin staining-of Klebsiella pneumoniae will allow for the visualization of the cell shape and the determination of the presence of a capsule. T/F

Which of the following microscopes produces the highest resolution images? A) scanning electronB) fluorescentC) differential interferenceD) atomic forceE) dark-field

93List and explain five types of techniques that can be used to identify unknown microorganisms. Oobservation and classification of the physical characteristics of an organism, which includes both cellular morphology and colony morphology Use of biochemical tests, such as fermentation of carbohydrates or production of metabolic by-products, to place microbes in different groups serological testing, in which antibodies are used todetect particular antigens on the surfaces of different microbes in an effort to distinguish closely related species or strains of microbes Phage typing is the fourth technique, which is the use of bacteriophages to infect bacterial cells Analyzing the genetic material of microbes, such as the percentage of G and C bases in a cell's DNA, to demonstrate possible relationships between species.

59Why does immersion oil improve resolution? A) It allows light to travel at a uniform speed on its way to the lens.B) It decreases the working distance.C) It increases the angle of refraction of the light.D) It increases numerical aperture and maintains a uniform light speed.E) It increases the numerical aperture.D) It increases numerical aperture and maintains a uniform light speed.

177Which of the following microscopes combines the greatest magnification with the best resolution? a. confocal microscope b. phase-contrast microscope c. dark-field microscope d. bright-field microscopea. confocal microscope

111Cells are differentiated after which step in Gram staining? crystal violet safranin alcohol decolization iodine none of the above C) alcohol decolorization

Which of the following is an INCORRECT pairing? A) magnification; refraction of radiationB) simple microscope; LeeuwenhoekC) contrast; staining techniquesD) electron beams; shorter wavelengthE) numerical aperture; curved glass