Question 1

A kitchen countertop has a spill of vegetable oil that was wiped up but a film remains.What should be the next step in disinfecting this surface?

Accepted Answer

A) 10% bleach 
B) spray a disinfectant that contains a heavy metal 
C) warm soapy scrub 
D) isopropanol 
E) chlorhexidine containing solution 
A) 10% bleach 
B) spray a disinfectant that contains a heavy metal 
C) warm soapy scrub 
D) isopropanol 
E) chlorhexidine containing solution

Question 2

Which of the following regarding antimicrobial control agents is FALSE?

Accepted Answer

A) Contaminating organic debris such as blood or sputum decrease effectiveness. 
B) Some agents kill by denaturing microbial cell proteins. 
C) Some agents affect microbial cell membranes by dissolving lipids. 
D) Silver-impregnated dressings are used for treating antibiotic-resistant bacteria. 
E) Alcohols effectively inactivate nonenveloped viruses by attacking lipids. 
A) Contaminating organic debris such as blood or sputum decrease effectiveness. 
B) Some agents kill by denaturing microbial cell proteins. 
C) Some agents affect microbial cell membranes by dissolving lipids. 
D) Silver-impregnated dressings are used for treating antibiotic-resistant bacteria. 
E) Alcohols effectively inactivate nonenveloped viruses by attacking lipids.

Question 3

An iodophor is a(n)

Accepted Answer

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

Question 4

Which of the following results in lethal damage to nucleic acids?

Accepted Answer

A) heat 
B) radiation 
C) certain chemicals 
D) heat and radiation 
E) heat,radiation,and some chemicals 
A) heat 
B) radiation 
C) certain chemicals 
D) heat and radiation 
E) heat,radiation,and some chemicals

Question 5

All of the following substances are effective against nonenveloped viruses EXCEPT

Accepted Answer

A) alcohol. 
B) chlorine. 
C) ethylene oxide. 
D) ozone. 
E) None of the answers is correct;all of these are equally effective against nonenveloped viruses. 
A) alcohol. 
B) chlorine. 
C) ethylene oxide. 
D) ozone. 
E) None of the answers is correct;all of these are equally effective against nonenveloped viruses.

Question 6

Moist heat destroys organisms by denaturing proteins.

Accepted Answer

A) True 
 B)False

Question 7

Bone and tendons for transplant are decontaminated by

Accepted Answer

A) ethylene oxide. 
B) glutaraldehyde. 
C) peroxygens. 
D) plasma sterilization. 
E) supercritical fluids. 
A) ethylene oxide. 
B) glutaraldehyde. 
C) peroxygens. 
D) plasma sterilization. 
E) supercritical fluids.

Question 8

Table 7.1
A disk-diffusion test using Staphylococcus gave the following results:
 $$\begin{array} { c c } 
\text { Disinfectant } & \text { Zone of inhibition } ( \mathrm { mm } ) \
 \text { A } & 0 \
\text { B } & 2.5 \
\text { C } & 10 \
\text { D } & 5
\end{array}$$
-In Table 7.1,which compound was the most effective against Staphylococcus?

Accepted Answer

A) A 
B) B 
C) C 
D) D 
E) The answer cannot be determined based on the information provided. 
A) A 
B) B 
C) C 
D) D 
E) The answer cannot be determined based on the information provided.

Question 9

Which chemical disinfectant can be considered a sterilizing liquid agent when appropriately applied?

Accepted Answer

A) quaternary ammonium compounds 
B) 70% ethanol 
C) sodium benzoate 
D) gluteraldehyde 
E) ethylene oxide 
A) quaternary ammonium compounds 
B) 70% ethanol 
C) sodium benzoate 
D) gluteraldehyde 
E) ethylene oxide

Question 10

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

Accepted Answer

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

Question 11

Assume that you are responsible for decontaminating materials in a large hospital.How would you sterilize each of the following? Briefly justify your answers.
a.a mattress used by a patient with bubonic plague
b.intravenous glucose-saline solutions
c.used disposable syringes
d.tissues taken from patients

Accepted Answer

a. To sterilize a mattress used by a pa

Question 12

Which one of the following is known to be most resistant to quaternary ammonium compounds?

Accepted Answer

A) gram positive bacteria 
B) members of the genus Pseudomonas 
C) members of the genus Staphylococcus 
D) fungi 
E) enveloped viruses 
A) gram positive bacteria 
B) members of the genus Pseudomonas 
C) members of the genus Staphylococcus 
D) fungi 
E) enveloped viruses

Question 13

If you were preparing nutrient agar at home and did not have an autoclave,what could you use to sterilize the nutrient agar?

Accepted Answer

A) bleach 
B) boiling for one hour 
C) hydrogen peroxide 
D) oven at 121°C for one hour 
E) pressure cooker at 121°C for 15 minutes 
A) bleach 
B) boiling for one hour 
C) hydrogen peroxide 
D) oven at 121°C for one hour 
E) pressure cooker at 121°C for 15 minutes

Question 14

Which of the following regarding antimicrobial control agents is FALSE?

Accepted Answer

A) Contaminating organic debris such as blood or sputum will decrease effectiveness. 
B) Some agents kill by denaturing microbial cell proteins. 
C) Some agents affect microbial cell membranes by dissolving lipids. 
D) Some agents are utilized as both an antiseptic and a disinfectant. 
E) Most chemical agents can achieve sterility. 
A) Contaminating organic debris such as blood or sputum will decrease effectiveness. 
B) Some agents kill by denaturing microbial cell proteins. 
C) Some agents affect microbial cell membranes by dissolving lipids. 
D) Some agents are utilized as both an antiseptic and a disinfectant. 
E) Most chemical agents can achieve sterility.

Question 15

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 decimal reduction time (D value)for the culture,which is defined as the time to reduce a population by one log,is approximately

Accepted Answer

A) 0 minutes. 
B) 10 minutes. 
C) 30 minutes. 
D) 40 minutes. 
E) 60 minutes. 
A) 0 minutes. 
B) 10 minutes. 
C) 30 minutes. 
D) 40 minutes. 
E) 60 minutes.

Question 16

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. 
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.

Question 17

Desiccation is a reliable form of sterilization.

Accepted Answer

A) True 
 B)False

Question 18

The thermal death time is the time needed to kill all the bacteria in a particular culture at a certain temperature.

Accepted Answer

A) True 
 B)False

Question 19

Which of the following pairs is mismatched?

Accepted Answer

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

Question 20

Table 7.3
The following data were obtained by incubating gram-positive bacteria in nutrient medium + disinfectant for 24 hours,then transferring one loopful to nutrient medium (subculturing).(+ = growth;- = no growth)
  
-In Table 7.3,which disinfectant was most effective against Salmonella?

Accepted Answer

A) Doom 
B) K.O. 
C) Mortum 
D) Sterl 
E) The answer cannot be determined based on the information provided. 
A) Doom 
B) K.O. 
C) Mortum 
D) Sterl 
E) The answer cannot be determined based on the information provided.

Exam 7: The Control of Microbial Growth

A kitchen countertop has a spill of vegetable oil that was wiped up but a film remains.What should be the next step in disinfecting this surface?

Which of the following regarding antimicrobial control agents is FALSE?

An iodophor is a(n)

Which of the following results in lethal damage to nucleic acids?

All of the following substances are effective against nonenveloped viruses EXCEPT

Moist heat destroys organisms by denaturing proteins.

Bone and tendons for transplant are decontaminated by

Table 7.1 A disk-diffusion test using Staphylococcus gave the following results: Disinfectant Zone of inhibition () A 0 B 2.5 C 10 D 5 -In Table 7.1,which compound was the most effective against Staphylococcus?

Which chemical disinfectant can be considered a sterilizing liquid agent when appropriately applied?

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

Which one of the following is known to be most resistant to quaternary ammonium compounds?

If you were preparing nutrient agar at home and did not have an autoclave,what could you use to sterilize the nutrient agar?

Which of the following regarding antimicrobial control agents is FALSE?

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

Desiccation is a reliable form of sterilization.

The thermal death time is the time needed to kill all the bacteria in a particular culture at a certain temperature.

Which of the following pairs is mismatched?

Table 7.3 The following data were obtained by incubating gram-positive bacteria in nutrient medium + disinfectant for 24 hours,then transferring one loopful to nutrient medium (subculturing).(+ = growth;- = no growth) -In Table 7.3,which disinfectant was most effective against Salmonella?

The Microbial World and You

Chemical Principles

Observing Microorganisms Through a Microscope

Functional Anatomy of Prokaryotic and Eukaryotic

Microbial Metabolism

Microbial Growth

Microbial Genetics

Biotechnology and Dna Technology

Classification of Microorganisms

The Prokaryotes: Domains Bacteria and Archaea

The Eukaryotes: Fungi, algae, protozoa, and Helminths

Viruses,viroids,and Prions

Principles of Disease and Epidemiology

Microbial Mechanisms of Pathogenicity

Innate Immunity: Nonspecific Defenses of the Host

Adaptive Immunity: Specific Defenses of the Host

Practical Applications of Immunology

Disorders Associated With the Immune System

Antimicrobial Drugs

Microbial Diseases of the Skin and Eyes

Microbial Diseases of the Nervous System

Microbial Diseases of the Cardiovascular and Lymphatic Systems

Microbial Diseases of the Respiratory System

Microbial Diseases of the Digestive System

Microbial Diseases of the Urinary and Reproductive Systems

Environmental Microbiology

Applied and Industrial Microbiology

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