LAB 5 TEST BANK
ENTERIC UNKNOWNS
The goal when dealing with enteric unknown is to determine the genus of the organism you have
A. True
B. False
Characteristics of all enterobacteraceae include
A. Gram negative rods
B. Oxidase negative
C. Catalase positive
D. Facultatiave anaerobes
E. If they are motile, they have peritrichous flagella, so the can run and tumble.
F. Only A, B, and C
G. All of the above
Coliforms are found in
A. The soil
B. Warm blooded animanls
C. Gastrointestinal tract
D. Both B and C
Methyl Red (MR) is a pH indicator that starts out yellow and becomes red if acid is present
A. True
B. False
If an organism has the ability to ferment sugars, the end products of the fermentation process are
A. Acids
B. Oxidase negative
C. Catalase positive
If the MR tube turns red, the organism was able to ferment sugars
A. False
B. True
What makes ENTEROBACTERACEAE motile?
A. Monotrichous flagella
B. peritrichous flagella
C. Neither, as they are not motile
What is an enzyme that breaks down milk sugar (lactose) into glucose and galactose?
A. Lactase
B. Hydrolase
C. Arginine dehydrogenase
D. None of the above
If an organism’s ADH test is red (positive) or yellow (negative), it is testing for the presence of which particular
enzyme?
A. Lactase
B. Hydrolase
C. Arginine dehydrogenase
D. None of the above
True or False?
When ADH breaks down argentine, it becomes ornithine, which is more basic
True
1
False
Phenol red, in the presence of ornithine, gets less red, although in the first 48 hours it may still be just orange.
True
False
When an animal dies, the smell of “death” is usually attributed to what?
A. Putrefaction
B. There is breakdown of a lot of protein
C. If an organism has the enzyme lysine decarboxylase, it will take lysine and break it down into cadaverine. A
decarboxylase breaks off a carboxyl group resulting in cadaverine.
D. All of the Above
True or False
ODC tests for decarboxylation of ornithine into putricine?
True
False
Fill in the blank:
ODC (Ornithine decarboxylase) is more _____1____, so phenol red turns ____2___.
A. 1-Basic, 2-Pink
B. 1-Acidic, 2-Red
C. 1-Basic, 2-Red
D. 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
B. Basic.
What is citric acid?
A. Contains citrate which is a salt of citric acid
B. A part of the Kreb’s cycle
C. Both of the above
D. Orange food coloring.
Arginine, argentine, lysine & ornithine are all examples of what?
A. Enzymes
B. Proteins
C. Sugars
D. Amino Acids
What qualities are present for Hydrogen sulfide gas?
A. Tests for sulfide production
B. Iron is added and turns black, means positive for presence of H 2S
C. Reduction of Thiosulfate (the substrate).
D. All of the above
Thiosulfate breaks down into ________ gas.
A. Carbon dioxide
B. Methane
C. Propane
D. Hydrogen Sulfide
This tests checks for the production of certain proteases (urease), which is an enzyme that breaks it down into
ammonia and carbon dioxide.
A. Urea
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B. Myrea
C. Uranus
D. None of the above
Which of the following are true in terms of Urea test?
A. The indicator is phenol red. Positive is red, negative is yellow.
B. Urea is made when proteins are broken down.
C. The smell of OLD urine is from ammonia.
D. Urea broth can also be used.
E. All of the above
Tryptophan deaminase (TDA) tests for the presence of ___________.
A. fat
B. turkey
C. pyruvic acid
D. blood
TRUE:
TRUE:
TRUE:
TRUE:
The same people who had a positive urea test will have a positive TDA test.
In an Indole test, it will form a red ring if positive, and be yellow if negative.
To test for indole, add Kovac’s reagent, which has alcohol in it.
In a Voges-Proskauer test, a positive test means the organism uses a fermentation pathway.
Voges-Proskauer test checks for the production of
A. acetoin
B. acetone
C. acid
The gel test is to determine the presence of an enzyme that breaks down gelatin
A. False
B. True
What happens if the gelatinase enzyme is present?
A. Makes the gelatin solid
B. it breaks the gelatin down and liquefies it
If the sugar tubes turn yellow, what does this indicate?
A. The tube has acid, so the sugars were used (broken down) by the bacteria
B. The tube has no acid, so the sugars were used (broken down) by the bacteria
C. The tube has acid, so the sugars were not used (broken down) by the bacteria
D. The tube has no acid, so the sugars were not used (broken down) by the bacteria
What is fermentation?
A. Aerobic respiration
B. Anaerobic respiration
What should all Enterobacteraceae be for glucose tests?
A. Negative
B. Positive
C. Neutral
TSI medium contains
.
A. Three sugars
B. Iron (Fe ++)
C. Thiosulfate (oxidized sulfur)
D. Phenol red (indicator where acids is yellow and basic is red)
E. All of the above
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When protein is digested, the pH becomes basic because of
A. Ammonic acids
B. Acids
C. Base
D. Glucose
.
Amino acid breaks down in to Co2 and ammonia. T
When protein is digested, the pH becomes
A. Acid
B. Base
C. Amino acids
D. Glucose
.
When sugar is fermented, the pH becomes
A. Acidic
B. Basic
C. Amino acid
D. Glucose
.
When sugars are fermented, the pH turns acidic because the byproducts are acids. T
A TSI slant that is yellow is recorded as A/A. T
A TSI slant that is red at the slant and yellow at the butt is recorded as K/A. T
If a sucrose or lactose is fermented, slant will be A/A because there is so much acid present, it overwhelms the little
bit of ammonia that was there. T
If glucose is fermented, more protein is degraded, so the ammonia will be stronger and show up as
A. Basic, K/A
B. Acidic, K/A
C. Iron (Fe ++)
D. A and B
.
What color will the MRVP broth turn by adding methyl red in a positive test?
a. Red
b. Blue
c. Green
d. white
What color will the MRVP broth turn in a negative methyl red test?
a. Yellow
b. Orange
c. Green
d. Both a and b
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 oxidized
b. It doesn’t
c. When deoxidized
d. All the time
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What will the litmus color be if the solution is acidic?
a. Pink
b. Purple
c. Blue
d. White
What will the litmus color be if the solution is basic?
a. Bluish
b. Reddish
c. Yellowish
d. white
True or False. The color will change in a Nitrate Reduction test if the test is positive.
True
What color will the solution turn if the test for is poisitive for nitrate?
a. Blue
b. Red
c. White
d. Green
What does one do if the solution does not turn red after adding the two regeants?
a. Add milk to detect lactase
b. Add zinc powder to detect for nitrogen
c. Add folic acid to test for iron
d. Nothing, the test failed, move on
What is the enzyme that breaks down H2O2 into H20 and O2?
a. Polymerase
b. Sucrase
c. Protease
d. Hey DrCatalase
True or False. If hydrogen peroxide is added to one of the wells and it bubbles the test is negative.False
True or false:
Methyl Red starts out yellow and becomes orange or red when acid is present True
Phenol Red starts out red and becomes yellow when acid is present True
Phenol Red is used for media with a lower pH than Methyl Red
In H2S gas, FeS gas is also present True
Bubbles due to nitrate reduction has Nitrogen gas present True
Bubbles after the addition of hydrogen peroxide means Oxygen is present True
The glucose broth after fermentation has Helium gas present False
What color would urea broth be if it produced ammonia?
A. Pink
B. Clear
C. Black
What color would urea broth be if it produced acid?
A. Yellow
B. Clear
C. Black
When testing for nitrate reduction, the presence of nitrite causes the tube to turn:
A. Red
B. White
C. Blue
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GRAM NEGATIVE ORGANISMS
When the color white is present in the Litmus milk test, what does it mean?
a. Curds formed
b. It fermented lactose and is acidic
c. Litmus was reduced and became clear
d. 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 formed
b. It fermented lactose and is acidic
c. Litmus was reduced and became clear
d. 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 formed
b. it fermented lactose and is acidic
c. Litmus was reduced and became clear
d. 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 curd
b. Curds formed
c. the pH is basic, so lactose was not fermented
d. the casein protein in the milk was broken down(proteolysis)
Match the letter designations to their color results in the litmus milk test
White R
Pink A
C
Bluish
K
R
Curds formed C
P
Gas formed
G
K
Brown ring
P
Motility Test: Which one is positive?
A. Tube 1
B. Tube 2
C. Tube 3
D. None of them
A
G
In Triple Sugar Iron (TSI) Slants, what does the A=?
A.
negative result
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B.
C.
D.
gas formation
Acid
None of the above
In Triple Sugar Iron (TSI) Slants, what does the K=?
A. Acid
B. Sulfide
C. Gas formation
D. negative result
In Triple Sugar Iron (TSI) Slants, what does the G=?
A. Acid
B. gas formation
C. negative result
D. None of the abobe
In Triple Sugar Iron (TSI) Slants, what does the H2S=?
A. Gas
B. Positive result
C. Negative result
D. sulfur was used, iron was reduced to black color
What does citrobacter freundii use as the source of carbon?
(A) Citrate
(B) Sodium phosphate
(C) Hydrogen
Where is citrobacter freundii bacteria found?
A) Fomite
B) Soil
C) Water
D) Human intestine
E) Sandflies
F) B, C, D
G) B, C, D, E
H) All of the above
What infections do citrobacter freundii cause?
A) Urinary Tract
B) B. cereus
C) Infant meningitis
D) A and C
E) None of the above
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.
FALSE (unable to sporulate)
The best method to kill all E. coli bacteria is sterilization.
effective for their eradication).
FALSE (Pasteurization or simple boiling are
Females can prevent urinary tract infection (UTI) by wiping front to back.
TRUE
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What infection(s) are caused by E.coli?
(A) Pneumonia
(B) Septicemia
(C) Meningitis
(D) Peritonitis
(E) All of the above
What antibiotic(s) is/are E. coli sensitive to?
(A) Streptomycin
(B) Gentamycin
(C) A and B
(D) None of the above
What do certain strains of E. coli, such as Escherichia coli O157:H7 produce?
E. a toxin and can cause food poisoning
F. produces nothing
G. a toxin causing cancer
H. None of the above
What is E. Coli Escherichia O157:H7 usually associated with?
E. eating raw eggs
F. drinking spoiled milk
G. eating cheese and contaminated meat
H. All of the above
The contaminated cheese and meat, associated with Escherichia coli O157:H7 are usually contaminated during or
shortly after slaughter or during storage or display.
I. TRUE
J. FLASE
What is the usual countermeasure for cooking suspect meat?
K. nothing
L. don’t buy meat
M. cook it “well done”
N. None of the above
What is the alternative of careful inspection of slaughtering and butchering methods?
O. to make sure that the animal’s colon is removed and not punctured
P. buy organic
Q. 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:H7
C. E. Coli
D. None of the above
Escherichia coli O157:H7 can be fatal particularly to young children, the elderly or the immunocompromised.
A. TRUE
B. FALSE
E. coli are susceptable to amoxicillin, cephalosporins, aminoglycosides, streptomycin, or gentamycin.
A. TRUE
B. FALSE
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Why is Antibiotic resistance is a growing problem for E. coli?
A. Some of this is due to overuse of antibiotics in humans
B. some of it is probably due to the use of antibiotics as growth promoters in food animals
C. None of the above
D. A and B
Enterobacter aerogenes is
A) A primary pathogen, causing illness in people with strong immune systems
B) An opportunistic pathogen, generally only causing disease in the immunocompromised
The most common site of infection from Enterobacter aerogenes is
A) Respiratory tract
B) Urinary tract
C) GI tract
D) All of the above
E) Both A and B only
Enterobacter, E. coli, and Klebsiella can be distinguished from other Gram negative rods by
A) Not being able to ferment lactose
B) Being a fast fermenter of lactose
Which all of the following describe Klebsiella pneumoniae?
A. nonmotile
B. encapsulated
C. lactose- fermenting
D. facultatively anaerobic
E. All of the above
Klebsiella pneumoniae is a normal flora of what areas?
A. mouth
B. skin
C. intestines
D. All of the above
Klebsiella pneumoniae naturally occurs in the soil?
A. True
B. false
Klebsiella pneumoniae can cause bacterial pneumonia, typically due to what?
A. Aspiration by alcoholics
B. being coughed on
C. inhalation of flatulence
D. None of the above
Klebsiella pneumoniae is most commonly implicated in what conditions?
A. Hospital-acquired urinary tract and wound infections, partically in immunocompromised individuals
B. gardening
C. patient care nurses
D. schools, particularly in children
Klebsiella pneumoniae ranks second to what bacteria for urinary tract infections in older persons?
A. salmonella typhi
B. helicobacter pylori
C. Escherichia coli
D. vibrio cholerae
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What is the most significant source of patient infection of Klebsiella pneumoniae?
A. soil
B. Feces
C. contaminated instruments
D. water/ food
Klebsiella pneumoniae is resistant to ampicillin but susceptible to what?
A. aminoglycosides
B. cephalosporins
C. Both aminoglycosides & cephalosporins
Which organism is responsible for many human urinary tract infections?
A. Klebsiella pneumoniae
B. Enterobacter
C. Citrobacter freundii
D. Proteus vulgaris
Some Proteus vulgaris are motile
True False
Proteus species do not ferment _________, are oxidase _________, and urease _________.
A. Fructose, positive, negative
B. Lactose, positive, negative
C. Fructose, negative, positive
D. Lactose, negative, positive
Providencia stuartii is a non-motile
True False
Providencia stuartii is a __________ pathogen.
A. Opportunistic
B. Obligate
C. Non-motile
D. 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 catheters
B. Extensive severe burns
C. Both A & B are correct
D. None of the above is true
What do the Salmonella organisms cause? Choose all that apply
A. Rash
C. foodborne illness
B. Typhoid fever
D. diarrhea
Salmonella species are _________________ and produce _________________.
A. Nonmotile, oxygen
C. motile, gas
B. Motile, hydrogen sulfide
D. nonmotile, hydrogen sulfide
True or false. Salmonella ferment lactose.
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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 have stopped the spread of
salmonella.
Salmonella can also be caught by handling this.
A. Snake
B. Turtle
C. gopher
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. Soap and water
Shigella Somnei is
A. Non motile
B. Non spore forming
C. H2S
D. All of the above
c. antimicrobial soap
D. hydrogen peroxide
.
The causative agent of human shigellosis is
A. Salmonella Enterica
B. Shigella Somnei
C. Providencia Stuartii
D. 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 contain
A. Blood
B. Mucus or Pus
C. A and B
Shigella causes dysentery that result in the destruction of the epithelial cells of the intestine. T
Some strains produce an enterotoxin similar to E.coli O157: H7. T
Symptoms of shigella Somnei usually begin
A. Right away after ingestion
B. 2 to 4 days after ingestion
C. After a week
D. After 2 weeks
.
Symptoms of shigella Somnei last for several days, but can last for weeks. T
Severe dysentery can be treated with
A. Antibody
B. Ampicillin
C. Penicillin
D. A and C
.
What does the “S” stand for in S. marcescens?
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A. Sure
B. Serratia
C. Sand
S. marcescens is a motile organism. True/ False
S. marcescens is involved in nosocomial infections, particularly urinary tract infections and wound infections. True/
False
S. marcescens prefers:
A. Damp conditions
B. Dry Conditons
C. Hot Conditions
What can cause complete eradication of the S. marcescens organism?
A. Alcohol
B. Bleach –based disinfectant
C. 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 cause
A. Conjunctivitis
B. Tear duct infections.
C. All of the above
Where is S. marcescens usually found in the restroom?
A. In the grout of the tile
B. On the sink
C. In the trash
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