LAB UNIT TWO TEST BANK

CH. 25 Questions

Pasteur and others observed that infecting an animal with ________ protected the animal against_______.a. Pseudomonas aeruginosa; Bacillus anthracisb. Bacillus anthracis; Pseudomonas aeruginosac. Staphylococcus aureus; Bacillus anthracisd. Bacillus anthracis; Pseudomonas aeruginosae. Bacillus anthracis; Bacillus anthracis

In 1928, Alexander Fleming found that culture filtrates of Penicillium inhibited the growth of many _______ of staphylococci.

a. gram-negativeb. gram-positive

Actinomycetes remain an important source of antibiotics. a. Trueb. False

Chemicals absorbed or used internally to fight infection are called what?a. Antibiotic drugsb. Synthetic drugsc. Antimicrobial drugsd. Natural drugs

A pathogen is a disease-inhibiting organism.a. Trueb. False

What is a Petri plate containing nutrient agar with antibiotic discs, inoculated uniformly over its entire surface called?

a. Agar-diffusion methodb. Complete-diffusion methodc. Disk-diffusion methodd. Petri-diffusion method

An effective antimicrobial agent will inhibit bacterial growth, and measurements can be made of the size of the zones of inhibition around the disks.

a. Trueb. False

The size of inhibition is affected by what factors?a. diffusion rate of the antimicrobial agent b. growth rate of organismc. diffusion rate of bacteriad. All of the abovee. A and B

What standardized test for agar diffusion is performed in clinical laboratories with strict quality controls?a. Fleming-Kirby testb. James-Kirby testc. Kirby-David testd. Kirby- Bauer test

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The minimum inhibitory concentration (MIC) of an antibiotic is determined by testing for bacterial growth in dilutions of the ______ in ______.

a. pathogen in nutrient agarb. pathogen in blood agarc. antibiotic in blood agard. antibiotic in nutrient agar

Who observed antibiosis around a Penicillium mold growth on a culture of staphylococci?A. Louis PasteurB. Alexander FlemingC. Paul EhrlichD. Robert Hook

In 1940, ___________ isolated the antibiotic streptomycin, produced by Actinomycetes.A. Alexander FlemingB. Louis PasteurC. Selman A. WaksmanD. Paul Ehrlich

Kirby-Bauer test uses Mueller-Hinton agar. TMueller-Hinton agar allows the antimicrobial agent to diffuse freely. T

The observation that some microbes inhibited the growth of others was made as early as A. 1800B. 1940C. 1874D. 1600

Chapter 45

What is secreted by the skin’s oil glands that inhibit bacterial growth?A. waterB. sebumC. saltD. sugar

What contributes to creating the skin’s hypertonic environment?A. waterB. sebumC. saltD. sugar

What are the normal microbes of the skin resistant to?a. Dryingb. High salt concentrationsc. waterd. A and B

Where are transient microbes generally most present on the body?A. ToesB. HandsC. ArmsD. All of the aboveE. B and C only

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What does Propionibacterium produce that maintains the pH of the skin?A. ammoniumB. propionic acidC. waterD. weak acids and bases

What pH level does the skin generally stay between?a. 1 and 2b. 3 and 4c. 3 and 5d. 4 and 6

What is the most common type of bacteria found on the skin?a. Gram negativeb. Gram positivec. Salt tolerantd. B and C

True or False. Staphylococcus aureus is normally found on the skin and is considered an opportunistic pathogen. TrueThe skin is generally an inhospitable environment for most microorganisms. TRUESalts in perspiration create a hypotonic environment. FALSE (hypertonic)Perspiration and sebum from the skin contribute to the environment of the normal microbiota of the skin. TRUEPropionibacterium live in hair follicles. True

The epidermis is composed of what type of cells?A) KeratinB) CollagenC) ElasticD) A and B

Choose from the following microbes that are part of the normal microbiota of the skin.A) StreptococcusB) Staph. aureusC) PropionibacteriumD) All of the aboveE) A and B onlyF) B and C only

Which agar is selective for salt-tolerant organisms?A) Nutrient agarB) EMB agarC) Mannitol salt agar

How is mannitol salt agar differential?A) Organisms that ferment mannitol will produce acidB) Indicator will turn medium yellow.C) Indicator will turn purple.D) A and BE) A and C

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What enzyme(s) does S. aureus produce?A) CatalaseB) CoagulaseC) Collagenase D) OxidaseE) All of the aboveF) A and B onlyG) A, B, and C only

What is the purpose of testing for the presence of coagulase?A) Distinguish S. aureus from other species of Staphylococcus.B) Distinguish S. aureus from proprionibacterium.C) Distinguish Gram positive from Gram negative organisms.D) All of the above.

What is an indicator of the presence of coagulase?A) ClumpingB) No clumping

CHAPTER 46

Alpha-hemolysis is ____________________________________________.A. No hemolysis, and no change in the blood agar around the colonyB. Green, cloudy zone around the colony. Partial destruction of RBC'sC. Complete hemolysis, giving a clear zone with a clean edge around the colonyD. All of the above

Beta-hemolysis is complete hemolysis, giving a clear zone with a clean edge around the colony.True False

Gamma-hemolysis is no hemolysis and no change in the blood agar around the colony.True False

The upper respiratory tract consists of the larynx and trachea.True False

The lower respiratory tract consists of the nose and throat. True False

Over 90% of streptococcal infections are caused by _________________.A. StreptococcusB. NeisseriaC. Beta-hemolytic group A streptococciD. Haemophilus

What does the lower respiratory tract consist of?A. bronchial tubes and alveoliB. trachea, bronchial tubes, and alveoliC. larynx, trachea, bronchial tubes, and alveoliB. throat, larynx, trachea, bronchial tubes, and alveoli C. nose, throat, larynx, trachea, bronchial tubes, and alveoli

Is the upper respiratory tract normally sterile?A. Yes

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B. NoIs the lower respiratory tract normally sterile?

A. YesB. NoC. Depends on how polluted the air is

Is it normal to find Staphylococcus, Streptococcus, Neisseria, and Haemophilus living in the throat?A. YesB. No

What are the predominant organisms in the throat cultures?A. Staphylococcus B. Streptococcus

What are hemolysins produced by?A. Staphylococcus B. StreptococcusC. Both A and B

CHAPTER 51

What does IMViC stand for?I indole production from breaking down tryptophanM methyl red test for acid production from breaking down glucoseV Voges-Proskauer test for production of acetoin from breaking down glucose in the butanediol pathwayC for the use of citrate as a sole carbon source

What method(s) have been developed that provide a large number of results from one inoculation?A: Rapid identification methods.

Why are systems developed to identify Enterobacteriaceae?A: To differentiate among the species contained within the two major groups of gram-negative organisms, known as the enterics (lactose fermenters) and the non-fermenters of lactose. Both groups are common causes of bacterial infections in humans.

Why is an oxidase test performed on a culture before using either an API 20E test strip or an Enterotube to identify the culture?

A: API 20E and Enterotube II are for the identification of oxidase- negative bacteria. If the oxidase test is positive, these two methods of identification would be useless.

Which of the following is TRUE regarding the BENEFITS of using the Enterotube? a. You find out everything you need to know about your unknownb. It provides quick results for a large number of tests from one inoculationc. Motility results are provided and are visible with the tube

Which of the following results are NOT provided from the Enterotube? a. Indoleb. Methyl redc. Voges-Proskauer (VP)d. Motilitye. citrate

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The IMViC tests were developed as a means of ________ members of the Enterobacteriaceae, particularly the _______, to determine if drinking water is contaminated with sewage.

a. Separating, coliformsb. Combining; coliformsc. Separating, pathogensd. Combining; pathogens

Comparisons between rapid identification methods and conventional culture methods show that they are as accurate as ________________.

a. Conventional beaker methodsb. Conventional test-tube methodsc. Conventional agar methodsd. Conventional petri-dish methods

ANTIMICROBIALS

True or False. The antibiotic with the largest zone of inhibition is the most effective one.False

Just because one zone is the largest, does NOT mean that is the most effective antibioticTrue

What types of organisms do narrow spectrum antibiotics kill?1. Either Gram positive or Gram negative, but not both2. Always Gram negative only3. Always Gram positive only4. Both gram positive and gram negative5. Neither Gram positive or Gram negative

What types of organisms do broad spectrum antibiotics kill?a. Either Gram positive or Gram negative, but not bothb. Always Gram negative onlyc. Always Gram positive onlyd. Both gram positive and gram negativee. Neither Gram positive or Gram negative

Why is it always good to be careful with broad spectrum antimicrobials?a. if there are a lot of gram negative bacteria, and you kill them, their endotoxins will be released in to the bloodstream and it could be fatal for the patientb. if there are a lot of gram positive bacteria, and you kill them, their endotoxins will be released in to the bloodstream and it could be fatal for the patientc. Both A and B are true

What is intermediate sensitivity of an antimicrobial drug?A. it implies clinical efficacy only in body sites where the drugs are physiologically concentratedB. it implies clinical efficacy only when higher than normal dose is usedC. it implies clinical efficacy if given two drugs at a lower dosage D. it implies clinical efficacy if the patient is given drugs they are only slightly allergic toE. Both A and B

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If a patient is allergic to the medication that needs to be prescribed for them, what is the next best option for their care?

A. choosing two antibiotics in the intermediate sensitivity categoryB. choosing two antibiotics in the sensitive categoryC. choosing two antibiotics in the resistant categoryD. choosing one antibiotic in the intermediate category

What is the zone of inhibition?A. the zone on the inner part of the disc with little bacterial growthB. the zone that is clear around the disc, with no bacterial growth.C. the zone that is covered with bacterial growth

What does the zone of inhibition measure?a. the effectiveness of the antimicrobials only when checked against the Kirby-Bauer chartb. the effectiveness of the antimicrobials only pertaining to intermediate level antibioticsc. the effectiveness of the antimicrobials only pertaining to sensitive level antibioticsd. the effectiveness of the antimicrobials only pertaining to resistant level antibiotics

ENTERIC UNKNOWNS

The goal when dealing with enteric unknown is to determine the genus of the organism you haveA. TrueB. False

Characteristics of all Enterobacteriaceae includeA. Gram negative rodsB. Oxidase negativeC. Catalase positiveD. Facultative anaerobesE. If they are motile, they have peritrichous flagella, so they can run and tumble.F. Only A, B, and CG. All of the above

Coliforms are found inA. The soilB. Warm blooded animalsC. Gastrointestinal tractD. Both B and C

Methyl Red (MR) is a pH indicator that starts out yellow and becomes red if acid is presentA. TrueB. False

If an organism has the ability to ferment sugars, the end products of the fermentation process areA. AcidsB. Oxidase negativeC. Catalase positive

If the MR tube turns red, the organism was able to ferment sugarsA. FalseB. True

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What is an enzyme that breaks down milk sugar (lactose) into glucose and galactose?A. LactaseB. HydrolaseC. Arginine dehydrogenaseD. None of the above

Arginine, lysine & ornithine are all examples of what?A. EnzymesB. ProteinsC. SugarsD. Amino Acids

When Arginine dehydrogenase breaks down argentine (an amino acid), it becomes ornithine (another amino acid), which is more basic.

A. TrueB. False

If an organism has the enzyme ornithine decarboxylase, what is ornithine broken down into?A. CadaverineB. PutrescineC. LysineD. Ornithine dioxide

Phenol red, in the presence of ornithine, gets less red, although in the first 48 hours it may still be just orange. A. TrueB. False

When an animal dies, the smell of “death” is usually attributed to what?A. PutrefactionB. There is breakdown of a lot of proteinC. If an organism has the enzyme lysine decarboxylase; it will take lysine and break off a carboxyl group to create cadaverine, which produces the cadaver smell.D. All of the Above

Ornithine decarboxylase turns the media more _____1____, so phenol red turns ____2___.A. 1-Basic, 2-PinkB. 1-Acidic, 2-RedC. 1-Basic, 2-RedD. 1-Acidic, 2-Pink

If an organism can use citrate as its only carbon source, the medium will become ________ because acid is breaking down.

A. Acidic (blue)B. Acidic (green)C. Basic (blue)D. Basic (green)

What is citrate?A. A salt of citric acidB. A part of the Krebs’s cycleC. Orange food coloringD. All of the aboveE. Both A and B

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When a medium contains iron and it turns black after inoculation with an organismA. Hydrogen sulfide has formed.B. Thiosulfate (the substrate) is reduced.C. The organism must be using sulfur as its terminal electron acceptor in the electron transport chain.D. All of the above

Urease is an enzyme that breaks downA. Particular sugarsB. Particular proteins

Urease breaks urea down into A. AmmoniaB. CO2C. UrineD. All of the aboveE. Both A and B only

Which of the following are true in terms of Urea test?A. The indicator is phenol red. B. Positive is pink, negative is yellow.C. Urea is made when proteins are broken down.D. The smell of OLD urine is from ammonia.E. All of the above

Tryptophan deaminase (TDA) tests for the presence of ___________.A. fatB. turkeyC. pyruvic acidD. blood

In an Indole test, a red ring is positive. TRUE: To test for indole, add Kovac’s reagent. TRUE: A positive Voges-Proskauer test means the organism uses the butanediol fermentation pathway. TRUE:

Voges-Proskauer test checks for the production ofA. acetoin B. acetoneC. acid

The gel test is to determine the presence of an enzyme that breaks down gelatinA. FalseB. True

What happens if the gelatinase enzyme is present?A. Makes the gelatin solidB. it breaks the gelatin down and liquefies it

If a sugar tubes turn yellow, what does this indicate?A. The tube has acid, so the sugars were used (broken down) by the bacteriaB. The tube has no acid, so the sugars were used (broken down) by the bacteriaC. The tube has acid, so the sugars were not used (broken down) by the bacteriaD. The tube has no acid, so the sugars were not used (broken down) by the bacteria

What is fermentation?A. Aerobic respiration

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B. Anaerobic respiration

TSI medium contains . A. Three sugarsB. Iron (Fe ++)C. Thiosulfate (oxidized sulfur)D. Phenol red (indicator where acids is yellow and basic is red)E. All of the above

When protein is digested, the pH becomes .A. AcidB. BaseC. Amino acidsD. Glucose

When sugar is fermented, the pH becomes .A. AcidicB. BasicC. Amino acidD. Glucose

A TSI slant that is all yellow is recorded as A/A. TRUE

A TSI slant that is red at the top and yellow at the butt is recorded as K/A. TRUE

A positive MRVP broth will be what color?a. Redb. Yellowc. Blued. Green

A negative MRVP broth will be what color?a. Redb. Yellowc. Blued. Green

True or false. In a litmus milk test, one must shake the tubes to mix the contents.False

When does litmus change color?a. When oxidizedb. It doesn’tc. When deoxidizedd. All the time

What will be the color of litmus milk if the solution is acidic?a. Pinkb. Purplec. Blued. White

What will be the color of litmus milk if the solution is basic?a. Bluishb. Reddishc. Yellowishd. white

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What color is a positive nitrate test?a. After adding the first two reagents, it turns redb. If there is no color change after adding the first two reagents, add zinc powder and it still does not turn redc. If there is no color change after adding the first two reagents, add zinc powder and it turns redd. Both A and Be. Both A and C

What is the enzyme that breaks down H2O2 into H20 and O2?a. Coagulaseb. Oxidasec. Catalased. Both A and Be. Both B and C

True or False. If hydrogen peroxide is added and it bubbles the test is negative for catalase. FalseMethyl Red starts out yellow and becomes red when acid is present TruePhenol Red starts out red and becomes yellow when acid is present TruePhenol Red is used for media with a lower pH than Methyl Red True

What color would urea broth be if it produced ammonia (positive test)?A. PinkB. ClearC. Black

What color would urea broth be if it produced acid (negative test)?A. YellowB. ClearC. Black

GRAM NEGATIVE ORGANISMS

When the color white is present in the Litmus milk test, what does it mean?A. Curds formedB. It fermented lactose and is acidicC. Litmus was reduced and became clearD. The casein protein in the milk was broken down.

When the color pink is present in the Litmus milk test, what does it mean?A. Curds formedB. It fermented lactose and is acidicC. Litmus was reduced and became clearD. the casein protein in the milk was broken down.

When the color blue is present in the Litmus milk test, what does it mean?A. Curds formedB. it fermented lactose and is acidicC. Litmus was reduced and became clearD. The pH is basic, so lactose was not fermented

What does the brown ring around the tube in the Litmus milk test mean?A. Gas in the curdB. Curds formed

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C. the pH is basic, so lactose was not fermentedD. the casein protein in the milk was broken down(proteolysis)

Match the letter designations to their color results in the litmus milk testWhite RPink ABluish KCurds formed CGas formed GBrown ring P

Motility Test: Which one is positive?A. Tube 1B. Tube 2C. Tube 3D. None of them

In Triple Sugar Iron (TSI) Slants, what does the A=?A. negative resultB. gas formationC. AcidD. None of the above

In Triple Sugar Iron (TSI) Slants, what does the K=?A. AcidB. Sulfide C. Gas formationD. negative result

In Triple Sugar Iron (TSI) Slants, what does the G=?A. AcidB. gas formationC. negative resultD. None of the above

In Triple Sugar Iron (TSI) Slants, what does the H2S=?A. Gas B. Positive resultC. Negative resultD. sulfur was used, iron was reduced to black color

What does Citrobacter freundii use as the source of carbon?(A) Citrate

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C RPKAG

(B) Sodium phosphate(C) Hydrogen

Where is Citrobacter freundii bacteria found?A) FomiteB) SoilC) WaterD) Human intestineE) SandfliesF) B, C, DG) B, C, D, EH) All of the above

What infections do Citrobacter freundii cause?A) Urinary TractB) Infant meningitisC) PneumoniaD) All of the aboveE) A and B only

What is Escherichia Coli (E. coli)?A) Gram negative, rod shaped bacteria living in gut flora.B) Gram positive, rod shaped bacteria living in gut flora.C) Gram negative, spiral shaped bacteria living in gut flora.D) Gram, positive, spiral shaped bacteria living in gut flora.

E. coli are able to sporulate (produce spores). FALSE

The best method to kill all E. coli bacteria is sterilization. FALSE (Pasteurization or simple boiling are effective for their eradication).

Females can help prevent urinary tract infections (UTI) by wiping front to back and avoiding rough vaginal sexual intercourse. TRUE

What infection(s) are caused by E.coli?(A) Pneumonia(B) Septicemia(C) Meningitis(D) Peritonitis(E) All of the above(F) A and B only

What antibiotic(s) is/are E. coli sensitive to?(A) Streptomycin(B) Gentamycin(C) amoxicillin (D) cephalosporin (E) aminoglycosides (F) All of the above(G) A and B only

What do certain strains of E. coli, such as Escherichia coli O157:H7 produce?

A. a toxin and can cause food poisoning B. produces nothingC. a toxin causing cancerD. None of the above

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What is E. Coli Escherichia O157:H7 usually associated with?A. eating raw eggsB. drinking spoiled milkC. eating cheese and contaminated milkD. All of the above

Contaminated cheese and meat, associated with Escherichia coli O157:H7 are usually contaminated during or shortly after slaughter or during storage or display.

A. TRUEB. FALSE

What is the usual countermeasure for cooking suspect meat?A. Microwave it firstB. don’t buy meatC. cook it “well done” D. None of the above

What is involved in careful inspection of slaughtering and butchering methods?A. to make sure that the animal’s colon is removed and not puncturedB. buy organicC. don’t buy meat

What is the strain of E. coli believed to be associated with the 2006 United States E. coli outbreak linked to fresh spinach?

A. there was not an outbreak B. Escherichia coli O157:H7C. E. ColitisD. None of the above

Escherichia coli O157:H7 can be fatal particularly to young children, the elderly or the immunocompromised.A. TRUEB. FALSE

What contributes to antibiotic resistance?A. Some of this is due to overuse of antibiotics in humansB. some of it is due to the use of antibiotics as growth promoters in food animals C. Patients stop taking their antibiotics before their bottle is emptyD. All of the aboveE. A and B only

Enterobacter aerogenes isA) A primary pathogen, causing illness in people with strong immune systemsB) An opportunistic pathogen, generally only causing disease in the immunocompromised

The most common site of infection from Enterobacter aerogenes isA) Respiratory tractB) Urinary tractC) GI tractD) All of the aboveE) Both A and B only

Enterobacter, E. coli, and Klebsiella can be distinguished from other Gram negative rods byA) Not being able to ferment lactose

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B) Being a fast fermenter of lactose

Which all of the following describe Klebsiella pneumoniae?A. non-motileB. encapsulatedC. lactose- fermentingD. facultative anaerobic E. All of the above

Klebsiella pneumoniae is a normal flora of what areas?A. mouthB. skinC. intestinesD. All of the above

Klebsiella pneumoniae naturally occurs in the soil?A. TrueB. false

Klebsiella pneumoniae can cause bacterial pneumonia, typically due to what?A. Aspiration by alcoholicsB. being coughed onC. inhalation of flatulenceD. None of the above

Klebsiella pneumoniae is most commonly implicated in what conditions?A. Hospital-acquired urinary tract and wound infections, particularly in immunocompromised individualsB. gardeningC. patient care nursesD. schools, particularly in children

Klebsiella pneumoniae ranks second to what bacteria for urinary tract infections in older persons?A. salmonella typhiB. helicobacter pyloriC. Escherichia coliD. vibrio cholerae

What is the most significant source of patient infection of Klebsiella pneumoniae?A. soilB. FecesC. contaminated instrumentsD. water/ food

Klebsiella pneumoniae is resistant to ampicillin but susceptible to what?A. aminoglycosidesB. cephalosporinsC. Both aminoglycosides & cephalosporins

Which organism is responsible for many human urinary tract infections?A. Klebsiella pneumoniaeB. EnterobacterC. Citrobacter freundiiD. Proteus vulgaris

All Proteus vulgaris are motileTrue False

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Proteus species do not ferment _________, are oxidase _________, and urease _________.A. Fructose, positive, negativeB. Lactose, positive, negativeC. Fructose, negative, positiveD. Lactose, negative, positive

Providencia stuartii is a non-motileTrue False

Providencia stuartii is a __________ pathogen.A. OpportunisticB. ObligateC. Non-motileD. All of the above

Strains of Providencia stuartii are sensitive to ampicillin. True False

Providencia stuartii can cause urinary tract infections in patients with______________________. A. Long term indwelling urinary cathetersB. Extensive severe burnsC. Both A & B are correctD. None of the above is true

What do the Salmonella organisms cause? Choose all that applyA. Rash C. foodborne illnessB. Typhoid fever D. diarrhea

Salmonella species are _________________ and produce _________________.A. Non-motile, oxygen C. motile, gasB. Motile, hydrogen sulfide D. non-motile, hydrogen sulfide

True or false. Salmonella ferment lactose.

True or False. Food poisoning from Salmonella is usually from poultry and raw eggs and from food that has been cooked or frozen, and not eaten straight away.

True or False. The overuse of antibiotics in both the poultry and beef industries has stopped the spread of salmonella.

Which organism is NOT likely to transmit Salmonella to humans?A. Snake C. gopherB. Turtle D. iguana

True or False. The prevention of Salmonella as a food illness involves effective sanitizing of food contact surfaces.

What is an effective topical sanitizer against Salmonella?A. Alcohol B. Bleach C. Soap and waterD. Antimicrobial soapE. Hydrogen peroxideF. Both A and B

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Shigella Somnei is .A. Non motileB. Non spore formingC. H2SD. All of the above

The causative agent of human shigellosis is .A. Salmonella entericaB. Shigella somneiC. Providencia stuartiiD. All of the above

Shigella infection is typically via fecal oral contamination. T

Ten bacterial cells can be enough to cause an infection. T

The stool of Shigella infections containA. BloodB. Mucus or PusC. A and B

Shigella causes dysentery that result in the destruction of the epithelial cells of the intestine. TSome strains of Shigella produce an enterotoxin similar to E.coli O157: H7. TSerratia marcescens is a motile organism. TrueS. marcescens is involved in nosocomial infections, particularly urinary tract and wound infections. True

S. marcescens prefers:A. Damp conditionsB. Dry ConditionsC. Hot Conditions

What can cause complete eradication of the S. marcescens organism?A. AlcoholB. Bleach –based disinfectantC. Lysol

Where is S. marcescens commonly found?A. Respiratory and urinary tracts of adults B. The gastrointestinal system of children. C. All of the above

S. marcescens can causeA. ConjunctivitisB. Tear duct infections.C. All of the above

Where is S. marcescens usually found in the restroom?A. In the grout of the tileB. On the sinkC. In the trash

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