Question 1

Which of the following does NOT achieve sterilization?

Accepted Answer

A)   supercritical fluids
B)   dry heat
C)   ethylene oxide
D)   pasteurization
E)   autoclave D

Question 2

Ethylene oxide

Accepted Answer

A)   requires high heat to be effective.
B)   is the active chemical in household bleach.
C)   is a sterilizing agent.
D)   is a good antiseptic.
E)   is not sporicidal.

Question 3

All of the following factors contribute to hospital- acquired infections EXCEPT

Accepted Answer

A)   some bacteria metabolize disinfectants.
B)   bacteria may be present in commercial products such as mouthwash.
C)   invasive procedures can provide a portal of entry for bacteria.
D)   gram- negative bacteria are often resistant to disinfectants.
E)   None of the answers is correct; all of these factors may contribute to hospital- acquired infection.

Question 4

Which of the following is the best method to sterilize heat- labile solutions?

Accepted Answer

A)   freezing
B)   membrane filtration
C)   dry heat
D)   pasteurization
E)   autoclave

Question 5

An iodophor is a(n)

Accepted Answer

A)   agent that reduces oxygen.
B)   form of formaldehyde.
C)   phenol.
D)   iodine mixed with a surfactant.
E)   quaternary ammonium compound.

Question 6

All of the following are methods of food preservation EXCEPT

Accepted Answer

A)   osmotic pressure.
B)   microwaves.
C)   high pressure.
D)   ionizing radiation.
E)   desiccation.

Question 7

Oxidizing agents include all of the following EXCEPT

Accepted Answer

A)   ozone.
B)   hydrogen peroxide.
C)   chlorine.
D)   glutaraldehyde.
E)   iodine. D

Question 8

Figure 7.2
Assume 109 E. coli cells/ml are in a flask.
 9 E. coli cells/ml are in a flask.    -Which graph in Figure 7.2 best depicts the effect of placing the culture in an autoclave for 15 minutes at time x? A)  a B)  b C)  c D)  d E)  e" class="answers-bank-image d-inline" rel="preload" >
-Which graph in Figure 7.2 best depicts the effect of placing the culture in an autoclave for 15 minutes at time x?

Accepted Answer

A)   a
B)   b
C)   c
D)   d
E)   e

Question 9

Application of heat to living cells can result in all of the following EXCEPT

Accepted Answer

A)   alteration of membrane permeability.
B)   breaking of hydrogen bonds.
C)   denaturation of enzymes.
D)   damage to nucleic acids.
E)   decreased thermal death time.

Question 10

Which of the following disinfectants acts by disrupting the plasma membrane?

Accepted Answer

A)   heavy metals
B)   soaps
C)   bisphenols
D)   halogens
E)   aldehydes

Question 11

All of the following are effective for destroying prions EXCEPT

Accepted Answer

A)   NaOH + autoclaving at 134°C.
B)   incineration.
C)   proteases.
D)   boiling.
E)   None of the answers are correct; each of these will destroy prions.

Question 12

Which of the following pairs is mismatched?

Accepted Answer

A)   alcohols - open wounds
B)   H2O2 - open wounds
C)   CuSO4 - algicide
D)   organic acids - food preservation
E)   Ag - wound dressings

Question 13

Figure 7.1
A suspension of 106 Bacillus cereus endospores was put in a hot- air oven at 170°C. Plate counts were used to determine the number of endospores surviving at the time intervals shown.
 6 Bacillus cereus endospores was put in a hot- air oven at 170°C. Plate counts were used to determine the number of endospores surviving at the time intervals shown.    -In Figure 7.1, the thermal death point for this culture is A)  15 minutes. B)  50°C. C)  170°C. D)  30 minutes. E)  The answer cannot be determined based on the information provided" class="answers-bank-image d-inline" rel="preload" >
-In Figure 7.1, the thermal death point for this culture is

Accepted Answer

A)   15 minutes.
B)   50°C.
C)   170°C.
D)   30 minutes.
E)   The answer cannot be determined based on the information provided

Question 14

Which of the following treatments is the most effective for controlling microbial growth?

Accepted Answer

A)   63°C for 30 minutes
B)   72°C for 15 seconds
C)   140°C for 4 seconds
D)   They are equivalent treatments.
E)   None of the answers is correct. D

Question 15

Which concentration of ethanol is the most effective bactericide?

Accepted Answer

A)   100 percent
B)   70 percent
C)   50 percent
D)   40 percent
E)   30 percent

Question 16

Desiccation is a reliable form of sterilization.

Accepted Answer

A) True 
 B)False

Question 17

Figure 7.1
A suspension of 106 Bacillus cereus endospores was put in a hot- air oven at 170°C. Plate counts were used to determine the number of endospores surviving at the time intervals shown.
 6 Bacillus cereus endospores was put in a hot- air oven at 170°C. Plate counts were used to determine the number of endospores surviving at the time intervals shown.    -In Figure 7.1, what is the thermal death time? A)  120 minutes B)  100°C C)  60 minutes D)  150°C E)  The answer cannot be determined based on the information provided." class="answers-bank-image d-inline" rel="preload" >
-In Figure 7.1, what is the thermal death time?

Accepted Answer

A)   120 minutes
B)   100°C
C)   60 minutes
D)   150°C
E)   The answer cannot be determined based on the information provided.

Question 18

Which of the following best describes the pattern of microbial death?

Accepted Answer

A)   All the cells in a culture die at once.
B)   The cells in a population die at a constant rate.
C)   The pattern varies depending on the species.
D)   The pattern varies depending on the antimicrobial agent.
E)   Not all of the cells in a culture are killed.

Question 19

Table 7.4
The results below were obtained from a use- dilution test of two disinfectants.
Cultures were inoculated into tubes with varying concentrations of disinfectants
and incubated for 24 hr at 20°C, then subcultured in nutrient media without disinfectants. (+ = growth; - = no growth)
 
-In Table 7.4, what is the minimal bacteriostatic concentration of each disinfectant? Which compound is bactericidal? At what concentration?

Accepted Answer

Without the actual data from Table 7.4, ...

Question 20

Figure 7.2
Assume 109 E. coli cells/ml are in a flask.
 9 E. coli cells/ml are in a flask.    -Which graph in Figure 7.2 best depicts the effect of placing the culture at 7°C at time x? A)  a B)  b C)  c D)  d E)  e" class="answers-bank-image d-inline" rel="preload" >
-Which graph in Figure 7.2 best depicts the effect of placing the culture at 7°C at time x?

Accepted Answer

A)   a
B)   b
C)   c
D)   d
E)   e

Exam 7: The Control of Microbial Growth

Which of the following does NOT achieve sterilization?

Correct Answer
verified
D

Ethylene oxide

Correct Answer
verified

All of the following factors contribute to hospital- acquired infections EXCEPT

Correct Answer
verified

Which of the following is the best method to sterilize heat- labile solutions?

Correct Answer
verified

An iodophor is a(n)

Correct Answer
verified

All of the following are methods of food preservation EXCEPT

Correct Answer
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Oxidizing agents include all of the following EXCEPT

Correct Answer
verified
D

Figure 7.2 Assume 10⁹E. coli cells/ml are in a flask. -Which graph in Figure 7.2 best depicts the effect of placing the culture in an autoclave for 15 minutes at time x?

Correct Answer
verified

Application of heat to living cells can result in all of the following EXCEPT

Correct Answer
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Which of the following disinfectants acts by disrupting the plasma membrane?

Correct Answer
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All of the following are effective for destroying prions EXCEPT

Correct Answer
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Which of the following pairs is mismatched?

Correct Answer
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Figure 7.1 A suspension of 10⁶Bacillus cereus endospores was put in a hot- air oven at 170°C. Plate counts were used to determine the number of endospores surviving at the time intervals shown. -In Figure 7.1, the thermal death point for this culture is

Correct Answer
verified

Which of the following treatments is the most effective for controlling microbial growth?

Correct Answer
verified
D

Which concentration of ethanol is the most effective bactericide?

Correct Answer
verified

Desiccation is a reliable form of sterilization.

Correct Answer
verified

Figure 7.1 A suspension of 10⁶Bacillus cereus endospores was put in a hot- air oven at 170°C. Plate counts were used to determine the number of endospores surviving at the time intervals shown. -In Figure 7.1, what is the thermal death time?

Correct Answer
verified

Which of the following best describes the pattern of microbial death?

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
Without the actual data from Table 7.4, ...
View Answer

Figure 7.2 Assume 10⁹E. coli cells/ml are in a flask. -Which graph in Figure 7.2 best depicts the effect of placing the culture at 7°C at time x?

Correct Answer
verified

Exam 7: The Control of Microbial Growth

Which of the following does NOT achieve sterilization?

Correct AnswerverifiedD

Ethylene oxide

Correct AnswerverifiedShow Answer

All of the following factors contribute to hospital- acquired infections EXCEPT

Correct AnswerverifiedShow Answer

Which of the following is the best method to sterilize heat- labile solutions?

Correct AnswerverifiedShow Answer

An iodophor is a(n)

Correct AnswerverifiedShow Answer

All of the following are methods of food preservation EXCEPT

Correct AnswerverifiedShow Answer

Oxidizing agents include all of the following EXCEPT

Correct AnswerverifiedD

Figure 7.2 Assume 109 E. coli cells/ml are in a flask. -Which graph in Figure 7.2 best depicts the effect of placing the culture in an autoclave for 15 minutes at time x?

Correct AnswerverifiedShow Answer

Application of heat to living cells can result in all of the following EXCEPT

Correct AnswerverifiedShow Answer

Which of the following disinfectants acts by disrupting the plasma membrane?

Correct AnswerverifiedShow Answer

All of the following are effective for destroying prions EXCEPT

Correct AnswerverifiedShow Answer

Which of the following pairs is mismatched?

Correct AnswerverifiedShow Answer

Figure 7.1 A suspension of 106 Bacillus cereus endospores was put in a hot- air oven at 170°C. Plate counts were used to determine the number of endospores surviving at the time intervals shown. -In Figure 7.1, the thermal death point for this culture is

Correct AnswerverifiedShow Answer

Which of the following treatments is the most effective for controlling microbial growth?

Correct AnswerverifiedD

Which concentration of ethanol is the most effective bactericide?

Correct AnswerverifiedShow Answer

Desiccation is a reliable form of sterilization.

Correct AnswerverifiedShow Answer

Figure 7.1 A suspension of 106 Bacillus cereus endospores was put in a hot- air oven at 170°C. Plate counts were used to determine the number of endospores surviving at the time intervals shown. -In Figure 7.1, what is the thermal death time?

Correct AnswerverifiedShow Answer

Which of the following best describes the pattern of microbial death?

Correct AnswerverifiedShow Answer

Correct AnswerAnswered by ExamLex AIWithout the actual data from Table 7.4, ...View AnswerShow Answer

Figure 7.2 Assume 109 E. coli cells/ml are in a flask. -Which graph in Figure 7.2 best depicts the effect of placing the culture at 7°C at time x?

Correct AnswerverifiedShow Answer

Correct Answer
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D

Correct Answer
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Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
D

Figure 7.2 Assume 10⁹E. coli cells/ml are in a flask. -Which graph in Figure 7.2 best depicts the effect of placing the culture in an autoclave for 15 minutes at time x?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Figure 7.1 A suspension of 10⁶Bacillus cereus endospores was put in a hot- air oven at 170°C. Plate counts were used to determine the number of endospores surviving at the time intervals shown. -In Figure 7.1, the thermal death point for this culture is

Correct Answer
verified

Correct Answer
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D

Correct Answer
verified

Correct Answer
verified

Figure 7.1 A suspension of 10⁶Bacillus cereus endospores was put in a hot- air oven at 170°C. Plate counts were used to determine the number of endospores surviving at the time intervals shown. -In Figure 7.1, what is the thermal death time?

Correct Answer
verified

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
Without the actual data from Table 7.4, ...
View Answer

Figure 7.2 Assume 10⁹E. coli cells/ml are in a flask. -Which graph in Figure 7.2 best depicts the effect of placing the culture at 7°C at time x?

Correct Answer
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