Deck 2: Tools of the Laboratory: Methods for the Culturing and Microscopic Analysis

Question 1

Which of the following is not a benefit of agar as a solid medium?

A)has flexibility
B)holds moisture
C)can be inoculated and poured at a temperature that is not harmful
D)is solid at room temperature
E)is digested by most microbes

Answer 1

E

Question 2

The three physical forms of laboratory media are

A)solid,liquid,and gas.
B)solid,semisolid,and liquid.
C)streak plate,pour plate,and broth.
D)aerobic,anaerobic,and micro aerobic.
E)None of the choices is correct.

Answer 2

B

Question 3

The correct microbiological term for the tiny sample of specimen that is put into a nutrient medium in order to produce a culture is the

A)colony.
B)inoculum.
C)streak.
D)loop.
E)None of the choices is correct.

Answer 3

B

Question 4

A nutrient medium that contains at least one ingredient that is NOT chemically definable would be termed

A)complex.
B)reducing.
C)enriched.
D)synthetic.
E)None of the choices is correct.

Question 5

A reducing medium contains

A)sugars that can be fermented.
B)extra oxygen.
C)hemoglobin,vitamins,or other growth factors.
D)substances that remove oxygen.
E)inhibiting agents.

Question 6

The term that refers to the purposeful addition of microorganisms into a laboratory nutrient medium is

A)isolation.
B)inoculation.
C)immunization.
D)infection.
E)contamination.

Question 7

Which type of media would be the best choice when shipping a sample of bacteria to a laboratory to be tested from a satellite office site?

A)transport
B)EMB
C)blood
D)thioglycollate
E)general purpose

Question 8

Agar is an important component of media because

A)bacteria require agar to grow.
B)agar inhibits mold growth.
C)agar provides a solid surface for bacterial growth.
D)agar prevents contamination.
E)All of the choices are correct.

Question 9

A pure culture contains

A)only one species of microorganism.
B)only bacteria.
C)a variety of microbes from one source.
D)a variety of species from the same genus.
E)None of the choices is correct.

Question 10

Which of the following is not an inoculating tool?

A)petri dish
B)loop
C)needle
D)pipette
E)swab

Question 11

Which of the following will result when 1% to 5% agar is added to nutrient broth,boiled,and cooled?

A)a pure culture
B)a mixed culture
C)a solid medium
D)a liquid medium
E)a contaminated medium

Question 12

Which method often results in colonies developing down throughout the agar along with some colonies on the surface?

A)streak plate
B)spread plate
C)pour plate
D)All of the choices are correct.
E)None of the choices is correct.

Question 13

Agar is a complex polysaccharide that comes from a(n)

A)green plant.
B)fungus.
C)mold.
D)algae.
E)euglena.

Question 14

A nutrient medium that has all of its chemical components identified,and their precise concentrations known and reproducible,would be termed

A)complex.
B)reducing.
C)enriched.
D)chemically defined.
E)None of the choices is correct.

Question 15

The Five I's of studying microorganisms include all of the following except

A)inoculation.
B)incubation.
C)infection.
D)isolation.
E)identification.

Question 16

What type of isolation technique is most effective for the majority of applications?

A)pour plate
B)streak plate
C)spread plate
D)loop dilution
E)culture plate

Question 17

Which of the following is essential for development of discrete,isolated colonies?

A)broth medium
B)differential medium
C)selective medium
D)solid medium
E)assay medium

Question 18

A common medium used for growing fastidious bacteria is

A)blood agar.
B)trypticase soy agar.
C)mannitol salt agar.
D)MacConkey medium.
E)a reducing medium.

Question 19

All of the following are examples of different types of microbiological media except

A)broth.
B)enriched.
C)agar.
D)petri dish.
E)selective.

Question 20

Which type of medium is able to distinguish different species or types of microorganisms based on an observable change in the colonies or in the medium?

A)differential
B)selective
C)enumeration
D)enriched
E)reducing

Question 21

Which of the following magnifies the specimen to produce its real image?

A)condenser
B)objective lens
C)ocular lens
D)body
E)nosepiece

Question 22

Which type of microscope is the most widely used and shows cells against a bright background?

A)bright field
B)dark field
C)phase contrast
D)fluorescence
E)electron

Question 23

Magnification is achieved in a compound microscope through the initial magnification of the specimen by the _____ lens.This image is then projected to the _____ lens that will further magnify the specimen to form a virtual image received by the eye.

A)ocular,objective
B)scanning,objective
C)objective,ocular
D)ocular,oil
E)None of the choices is correct.

Question 24

Which of the following characteristics refers to the microscope's ability to show two separate entities as separate and distinct?

A)resolving power
B)magnification
C)refraction
D)All of the choices are correct.
E)None of the choices is correct.

Question 25

A rod-shaped bacterium is measured as 0.3 micrometers ( $\mu$ m)in length using an ocular micrometer.Your instructor wants you to report the length in millimeters (mm)to test your understanding of metric conversions.What is the length of the organism in millimeters?

A)300 mm
B)0.0003 mm
C)0.03 mm
D)3 mm

Question 26

Which of the following magnifies the specimen to produce its virtual image?

A)objective lens
B)ocular lens
C)condenser
D)body
E)iris diaphragm

Question 27

The _____ of the microscope holds and allows selection of the objective lenses.

A)stage
B)condenser
C)objective
D)ocular
E)nosepiece

Question 28

Which type of microscope shows cells against a bright background but also differentiates intracellular structures of unstained cells based on their varying densities?

A)bright field
B)dark field
C)phase contrast
D)differential interference
E)electron

Question 29

Differential media results in which of the following growth characteristics?

A)different color colonies
B)different media color post incubation
C)precipitates
D)gas bubbles
E)All of the choices are correct.

Question 30

Bacteria that require special growth factors and complex nutrients are termed

A)aerobic.
B)anaerobic.
C)fastidious.
D)microaerophilic.
E)autotrophic.

Question 31

A microbiologist must culture a patient's feces for intestinal pathogens.Which of the following would likely be present in selective media for analyzing this fecal specimen?

A)NaCl
B)sheep red blood cells
C)bile salts
D)thioglycollic acid
E)peptone

Question 32

An enveloped virus measures 0.02 micrometers ( $\mu$ m)in diameter.What is the diameter of this virus in nanometers (nm)?

A)2 nm
B)20 nm
C)0.00002 nm
D)0.2 nm

Question 33

All of the following are diameters of cells that would be resolved in a microscope with a 0.2 µm limit of resolution except

A)0.2 µm.
B)0.2 mm.
C)0.1 µm.
D)0.3 µm.
E)2.0 µm.

Question 34

A reducing media is used to culture

A)fastidious organisms.
B)aerobic organisms.
C)anaerobic organisms.
D)any pathogenic organisms.
E)None of the choices is correct.

Question 35

A microbiologist inoculates Staphylococcus aureus into a culture medium.Following incubation,both Staphylococcus aureus and Staphylococcus epidermidis are determined to be growing in this culture.What is the most likely explanation?

A)The microbiologist used too much inoculum.
B)The culture is contaminated.
C)The incubation temperature was incorrect.
D)The culture medium must be selective.
E)The culture medium must be differential.

Question 36

Newly inoculated cultures must be _____ at a specific temperature to encourage growth.

A)streaked
B)poured
C)incubated
D)contaminated
E)All of the choices are correct.

Question 37

The type of microscope in which you would see brightly illuminated specimens against a black background is

A)bright field.
B)dark field.
C)phase contrast.
D)fluorescence.
E)electron.

Question 38

For which bacterial genus does mannitol salt agar differentiate between species?

A)Salmonella
B)Streptococcus
C)Neisseria
D)Staphylococcus
E)Escherichia

Question 39

If a microbiologist is studying a specimen at a total magnification of 950x,what is the magnifying power of the objective lens if the ocular lens is 10x?

A)100x
B)950x
C)85x
D)850x
E)95x

Question 40

Which of the following controls the amount of light entering the specimen?

A)objective lens
B)ocular lens
C)condenser
D)body
E)iris diaphragm

Question 41

Normal incubation temperatures range from 30 ^$\circ$ C to 60 ^$\circ$ C.

Question 42

One colony typically develops from the growth of several parent bacterial cells.

Question 43

The real image is the reverse of the actual specimen.

Question 44

The Gram staining procedure is best described as a(n)__ staining technique.

A)acid-fast or Ziehl-Neelson
B)differential
C)capsule
D)Schaefer-Fulton
E)simple

Question 45

Which type of microscope bombards a whole,metal-coated specimen with electrons moving back and forth over it?

A)fluorescence
B)differential interference contrast
C)scanning electron
D)transmission electron
E)phase contrast

Question 46

Bacterial cultures are easily identified from their microscopic appearance.

Question 47

The specimen preparation that is best for viewing cell motility is

A)hanging drop.
B)fixed stained smear.
C)Gram stain.
D)negative stain.
E)flagellar stain.

Question 48

All of the following pertain to the fluorescence microscope except it

A)uses electrons to produce a specimen image.
B)is a type of compound microscope.
C)requires the use of dyes like acridine and fluorescein.
D)is commonly used to diagnose certain infections.
E)requires an ultraviolet radiation source.

Question 49

What do the Gram stain,acid-fast stain,and endospore stain have in common?

A)They are used on a wet mount of the specimen.
B)They use heat to force the dye into cell structures.
C)The outcome is based on cell differences.
D)They use a negative stain technique.
E)They are simple stains.

Question 50

The purpose of staining cells on a microscope slide is to

A)kill them.
B)secure them to the slide.
C)enlarge the cells.
D)add contrast in order to see them better.
E)see motility.

Question 51

A microbiologist makes a fixed smear of bacterial cells and stains them with Loeffler's methylene blue.All the cells appear blue under the oil lens.This is an example of

A)negative staining.
B)using an acidic dye.
C)simple staining.
D)using the acid-fast stain.
E)capsule staining.

Question 52

A confocal scanning microscope

A)uses visible light to form a specimen image.
B)shows three-dimensional cell images from the cell surface to the middle of the cell.
C)produces specimen images on electron micrographs.
D)uses dyes that emit visible light when bombarded by electrons.
E)requires specimens to be stained.

Question 53

Basic dyes are

A)attracted to the negatively charged acidic substances of bacterial cells.
B)anionic.
C)used in negative staining.
D)repelled by cells.
E)dyes such as India ink and nigrosin.

Question 54

Which type of microscope achieves the greatest resolution and highest magnification?

A)bright field
B)dark field
C)phase contrast
D)fluorescence
E)electron

Question 55

A selective medium contains one or more substances that inhibit growth of certain microbes in order to facilitate the growth of other microbes.

Question 56

The bending of light rays as they pass from one medium to another is called refraction.

Question 57

Which type of microscope does not use light in forming the specimen image?

A)bright field
B)dark field
C)phase contrast
D)fluorescence
E)electron

Question 58

Mixed cultures are also referred to as contaminated cultures.

Question 59

The procedures for culturing a microorganism require the use of a microscope.

Question 60

Some microbes are not capable of growing on artificial media.

Question 61

A differential interference contrast microscope uses dyes to give colored three-dimensional images.

Question 62

When utilizing a light microscope,the specimen on the glass slide must be in proper position to ensure illumination of the specimen for visualization.This is done by placing the glass slide

A)between the condenser lens and the objective lens.
B)directly on top of the light source.
C)between the ocular lens and the objective lens.
D)between the light source and the condenser lens.

Question 63

You understand that a microscopic view is needed to visualize microbes that fall within the 1-10 µm micrometer size range but also to detect characteristic ferning of amniotic fluid.Which type of microscope will be used by the laboratory technicians to make these observations of the patient sample?

A)electron microscope
B)light microscope
C)confocal microscope
D)fluorescent microscope

Question 64

Although microscopic analysis revealed the presence of grapelike clusters of gram-positive cocci,you know that the species identification of the organism will require biochemical testing.Biochemical tests aid in microbial identification by providing information on

A)cell morphology.
B)asexual reproduction.
C)cellular metabolism.
D)DNA sequences.

Question 65

No ferning of the vaginal fluid is detected,and you reassure your patient that her membranes have not ruptured.You explain that the laboratory technicians will use which five basic techniques (in order)to manipulate,grow,examine,and characterize any microorganisms present in the collected specimens?

A)isolation,incubation,inspection,identification,and inoculation
B)inspection,identification,isolation,incubation,and inoculation
C)identification,isolation,incubation,inspection,and inoculation
D)inoculation,incubation,isolation,inspection,and identification

Question 66

Ms.Hungh's acid-fast stain results returned inconclusive for the presence of AFBs (acid-fast bacilli).Therefore,culturing of the sputum is performed in order to isolate microbial growth for further analysis.Which medium would be utilized to select for the growth of Mycobacterium species if present in the sample?

A)blood agar
B)Lowenstein-Jensen
C)MacConkey agar
D)Sabouraud's agar

Question 67

Culturing of the sputum resulted in the growth of distinct colonies on the medium,and the technician informs you that further isolation by subculturing is now needed.You understand that this is accomplished by taking a bit of growth from an isolated colony and inoculating a separate medium,resulting in the production of a

A)diagnosis.
B)pure culture.
C)broth.
D)mixed culture.

Question 68

Fixed smears of specimens are required in order to perform the Gram stain and endospore stain on the specimens.

Question 69

The patient asks how microbes from her body can be grown in the lab.You explain that specimens are introduced to nutrient medium and that any growth of the microbe that appears after incubating the specimen is called the

A)colony.
B)culture.
C)microorganism.
D)infectious agent.

Question 70

Cultures and specimens pose a potential employee and public health hazard,and require proper handling and disposal via specific medical waste policies.Some facilities,such as the ATCC,are regulated to maintain living catalogs of specimens for research and educational purposes.Such collections are referred to as

A)live microbes.
B)stock cultures.
C)dangerous microbes.
D)bacteriological reserve.

Question 71

Mr.Nowak's lab results return positive for Staphylococcus.You understand that the culture most likely required growth on a complex medium,consisting of

A)an exact chemical formula.
B)a simple pure compound.
C)at least one ingredient that is not chemically defined.
D)chemical inhibitors.

Question 72

A sputum sample is ordered for microbial analysis in order to rule out the diagnosis of tuberculosis.Suspecting Mycobacterium tuberculosis may be the pathogen,you know that the laboratory technicians will perform which stain on the sample?

A)endospore stain
B)negative stain
C)flagellar stain
D)acid-fast stain

Question 73

At the end of the Gram stain,gram-positive bacteria will be seen as red/pink cells.

Question 74

Gram stain results from the patient specimen indicate a bacterial infection.From your microbiology course,you remember that this staining procedure involves

A)forcing a dye into resistant bodies with heat to distinguish between spores and cells.
B)timed,sequential applications of crystal violet dye,iodine,an alcohol rinse,and a contrasting counterstain to the sample.
C)application of the dye,carbol fuchsin,followed by an acid alcohol rinse.
D)application of India ink to detect the presence of bacterial capsules.