Question 1

Which of the following is (are) considered when selecting a germicidal chemical?

Accepted Answer

A)  Toxicity AND cost 
B)  Cost AND compatibility with the material being treated 
C)  Compatibility with the material being treated AND environmental impact 
D)  Environmental impact, toxicity AND cost 
E)  All of the answer choices are correct. 
A)  Toxicity AND cost 
B)  Cost AND compatibility with the material being treated 
C)  Compatibility with the material being treated AND environmental impact 
D)  Environmental impact, toxicity AND cost 
E)  All of the answer choices are correct.

Question 2

Please select the INCORRECTLY matched pair.

Accepted Answer

A)  Bacterial endospores - highly resistant. 
B)  D-value - time to destroy 10% of microbes present. 
C)  Critical instrument - scalpels and needles. 
D)  Incineration - burns cells to ashes. 
E)  Sterilants - destroy all microbes including endospores and viruses. 
A)  Bacterial endospores - highly resistant. 
B)  D-value - time to destroy 10% of microbes present. 
C)  Critical instrument - scalpels and needles. 
D)  Incineration - burns cells to ashes. 
E)  Sterilants - destroy all microbes including endospores and viruses.

Question 3

If a process kills 90% of the organisms per minute, how many minutes would it take to kill all organisms when starting with 100,000 organisms?

Accepted Answer

A)  6 minutes 
B)  3 minutes 
C)  2 minutes 
D)  1 minute 
E)  60 minutes 
A)  6 minutes 
B)  3 minutes 
C)  2 minutes 
D)  1 minute 
E)  60 minutes

Question 4

Typical conditions used for sterilization are

Accepted Answer

A)  100°C for 10 minutes. 
B)  121°C at 15 psi for 15 minutes. 
C)  80°C for 15 minutes. 
D)  72°C for 15 seconds. 
E)  100°C for 10 seconds. 
A)  100°C for 10 minutes. 
B)  121°C at 15 psi for 15 minutes. 
C)  80°C for 15 minutes. 
D)  72°C for 15 seconds. 
E)  100°C for 10 seconds.

Question 5

Chlorine

Accepted Answer

A)  readily reacts with organics to produce potentially carcinogenic trihalomethanes. 
B)  is expensive but is able to destroy all types of microorganisms. 
C)  is unaffected by the presence of organic material. 
D)  is ineffective when diluted. 
E)  can be used effectively as an antiseptic. 
A)  readily reacts with organics to produce potentially carcinogenic trihalomethanes. 
B)  is expensive but is able to destroy all types of microorganisms. 
C)  is unaffected by the presence of organic material. 
D)  is ineffective when diluted. 
E)  can be used effectively as an antiseptic.

Question 6

A suffix used to describe a killing action would be

Accepted Answer

A)  -static. 
B)  -cidal. 
C)  -cillin. 
D)  -tion. 
E)  -side. 
A)  -static. 
B)  -cidal. 
C)  -cillin. 
D)  -tion. 
E)  -side.

Question 7

Hexachlorophene has been particularly effective against

Accepted Answer

A)  Staphylococcus aureus. 
B)  Micrococcus aureus. 
C)  Escherichia coli. 
D)  Enterobacter aerogenes. 
E)  Streptococcus pneumoniae. 
A)  Staphylococcus aureus. 
B)  Micrococcus aureus. 
C)  Escherichia coli. 
D)  Enterobacter aerogenes. 
E)  Streptococcus pneumoniae.

Question 8

Chlorhexidine

Accepted Answer

A)  is an aldehyde. 
B)  is extensively used in antiseptics. 
C)  is ineffective against vegetative bacteria. 
D)  is limited in use due to its high toxicity. 
E)  commonly causes adverse side effects. 
A)  is an aldehyde. 
B)  is extensively used in antiseptics. 
C)  is ineffective against vegetative bacteria. 
D)  is limited in use due to its high toxicity. 
E)  commonly causes adverse side effects.

Question 9

Gamma irradiation

Accepted Answer

A)  has not been approved for use on food. 
B)  can be used to either sterilize or pasteurize, depending on the dose of radiation. 
C)  leaves some radioactive particles in the treated substance. 
D)  usually kills by generating heat and denaturing proteins. 
E)  frequently causes a product to become carcinogenic. 
A)  has not been approved for use on food. 
B)  can be used to either sterilize or pasteurize, depending on the dose of radiation. 
C)  leaves some radioactive particles in the treated substance. 
D)  usually kills by generating heat and denaturing proteins. 
E)  frequently causes a product to become carcinogenic.

Question 10

Silver sulfadiazine, a combination of silver and a sulfa drug, is used to

Accepted Answer

A)  disinfect water for drinking. 
B)  prevent infection of surgical wounds. 
C)  prevent infection of second- and third-degree burns. 
D)  counteract lead poisoning. 
E)  prevent ophthalmia neonatorum in babies. 
A)  disinfect water for drinking. 
B)  prevent infection of surgical wounds. 
C)  prevent infection of second- and third-degree burns. 
D)  counteract lead poisoning. 
E)  prevent ophthalmia neonatorum in babies.

Question 11

Hydrogen peroxide may be used as a sterilant on living tissue.

Accepted Answer

A) True 
 B)False

Question 12

Jasmine's boyfriend Paul has a large boil on his back. The boil is very painful to touch, and is surrounded by an area of redness that is warm to the touch. Jasmine tells you that she and Paul have decided that Jasmine will "pop" the boil later that evening when they are both home from school. You ask Jasmine what she plans to use to open the boil and she tells you she has a knife with a sharp point that she will use, and that she will wash it well with dishwashing detergent before she uses it.

-You tell Jasmine that there are various ways that she can in fact sterilize the knife she plans to use. Which of the following is unlikely to be available to Jasmine for sterilizing her knife in her home?

Accepted Answer

A)  Household bleach, used at a 1:100 dilution. 
B)  Heating the knife in a flame, such as that on a gas stove. 
C)  Irradiating the knife with gamma rays. 
D)  Cleaning the knife with rubbing alcohol from the pharmacy. 
E)  Heating the knife to a high temperature in the oven. 
A)  Household bleach, used at a 1:100 dilution. 
B)  Heating the knife in a flame, such as that on a gas stove. 
C)  Irradiating the knife with gamma rays. 
D)  Cleaning the knife with rubbing alcohol from the pharmacy. 
E)  Heating the knife to a high temperature in the oven.

Question 13

Pasteurization

Accepted Answer

A)  is the use of heat to sterilize food products. 
B)  is a process that uses intense cold to kill microorganisms on foods. 
C)  is the use of heat to reduce numbers of pathogenic/spoilage bacteria in a food item to a safe level. 
D)  is a process that uses short bursts of radiation to kill microorganisms on foods. 
E)  is a process used to preserve only milk and milk products. 
A)  is the use of heat to sterilize food products. 
B)  is a process that uses intense cold to kill microorganisms on foods. 
C)  is the use of heat to reduce numbers of pathogenic/spoilage bacteria in a food item to a safe level. 
D)  is a process that uses short bursts of radiation to kill microorganisms on foods. 
E)  is a process used to preserve only milk and milk products.

Question 14

Generally, heavy metals, except silver, have been proven to be too toxic for use on human tissue and are no longer used medically.

Accepted Answer

A) True 
 B)False

Question 15

Hand washing with plain soap is very effective in controlling spread of microorganisms because

Accepted Answer

A)  plain soap is bacteriostatic and inhibits bacterial growth. 
B)  it is very effective at the mechanical removal of microorganisms. 
C)  all soaps are virucidal and kill all viruses. 
D)  plain soap is bactericidal and kills all bacteria. 
E)  all soaps are bacteriostatic and kill endospores. 
A)  plain soap is bacteriostatic and inhibits bacterial growth. 
B)  it is very effective at the mechanical removal of microorganisms. 
C)  all soaps are virucidal and kill all viruses. 
D)  plain soap is bactericidal and kills all bacteria. 
E)  all soaps are bacteriostatic and kill endospores.

Question 16

Generally, membrane filters are not used to remove

Accepted Answer

A)  bacteria from liquids. 
B)  enzymes from liquids. 
C)  microorganisms from gases. 
D)  spoilage agents from alcoholic beverages. 
E)  bacteria from nutrient broths. 
A)  bacteria from liquids. 
B)  enzymes from liquids. 
C)  microorganisms from gases. 
D)  spoilage agents from alcoholic beverages. 
E)  bacteria from nutrient broths.

Question 17

Microbial death rates may be affected by

Accepted Answer

A)  pH. 
B)  temperature. 
C)  the presence of organics. 
D)  growth in a biofilm. 
E)  All of the answer choices are correct. 
A)  pH. 
B)  temperature. 
C)  the presence of organics. 
D)  growth in a biofilm. 
E)  All of the answer choices are correct.

Question 18

You go hiking with some friends in a nearby national park. The weather is cool when you set out but it quickly becomes very warm. Neither you nor your friends are carrying enough water. Eventually you find a stream and because you are so thirsty, you drink from it. About a week later you start to feel unwell. You have vomiting, abdominal cramps, and explosive diarrhea (loud, severe diarrhea). Your stool seems kind of oily and is difficult to flush away. You tell your RN brother about your signs and symptoms, and he tells you he thinks you may have giardiasis, caused by the protozoan Giardia lamblia.
-Which of the following statements is False regarding Giardia?

Accepted Answer

A)  It contains 80S ribosomes. 
B)  It is aquatic. 
C)  It has a phospholipid cytoplasmic membrane. 
D)  It has a peptidoglycan cell wall. 
E)  It's DNA is contained within a membrane. 
A)  It contains 80S ribosomes. 
B)  It is aquatic. 
C)  It has a phospholipid cytoplasmic membrane. 
D)  It has a peptidoglycan cell wall. 
E)  It's DNA is contained within a membrane.

Question 19

You go hiking with some friends in a nearby national park. The weather is cool when you set out but it quickly becomes very warm. Neither you nor your friends are carrying enough water. Eventually you find a stream and because you are so thirsty, you drink from it. About a week later you start to feel unwell. You have vomiting, abdominal cramps, and explosive diarrhea (loud, severe diarrhea). Your stool seems kind of oily and is difficult to flush away. You tell your RN brother about your signs and symptoms, and he tells you he thinks you may have giardiasis, caused by the protozoan Giardia lamblia.
-You ask your brother which method of eliminating microbes is the best in general. He tells you that there is no one perfect method and that various factors must be taken into account when considering any antimicrobial approach. These include all of the following EXCEPT

Accepted Answer

A)  the type of microbes to be controlled. 
B)  environmental conditions such as temperature. 
C)  whether a potential infection can be easily treated. 
D)  situational considerations (is a method practical for the situation?). 
E)  the number of microbes to be controlled. 
A)  the type of microbes to be controlled. 
B)  environmental conditions such as temperature. 
C)  whether a potential infection can be easily treated. 
D)  situational considerations (is a method practical for the situation?). 
E)  the number of microbes to be controlled.

Question 20

In a one D process, how many D values would it take to reduce a population of 10¹⁰ cells to one survivor?

Accepted Answer

A)  2 
B)  4 
C)  5 
D)  10 
E)  100 
A)  2 
B)  4 
C)  5 
D)  10 
E)  100

Exam 5: Control of Microbial Growth

Which of the following is (are) considered when selecting a germicidal chemical?

Please select the INCORRECTLY matched pair.

If a process kills 90% of the organisms per minute, how many minutes would it take to kill all organisms when starting with 100,000 organisms?

Typical conditions used for sterilization are

Chlorine

A suffix used to describe a killing action would be

Hexachlorophene has been particularly effective against

Chlorhexidine

Gamma irradiation

Silver sulfadiazine, a combination of silver and a sulfa drug, is used to

Hydrogen peroxide may be used as a sterilant on living tissue.

Pasteurization

Generally, heavy metals, except silver, have been proven to be too toxic for use on human tissue and are no longer used medically.

Hand washing with plain soap is very effective in controlling spread of microorganisms because

Generally, membrane filters are not used to remove

Microbial death rates may be affected by

In a one D process, how many D values would it take to reduce a population of 10¹⁰ cells to one survivor?

Humans and the Microbial World

The Molecules of Life

Microscopy and Cell Structure

Dynamics of Microbial Growth

Microbial Metabolism: Fueling Cell Growth

The Blueprint of Life, from DNA to Protein

Bacterial Genetics

Biotechnology

Identifying and Classifying Microorganisms

The Diversity of Bacteria and Archaea

The Eukaryotic Members of the Microbial World

Viruses, Viroids, and Prions

The Innate Immune Response

The Adaptive Immune Response

Host-Microbe Interactions

Immunological Disorders

Applications of Immune Responses

Epidemiology

Antimicrobial Medications

Respiratory System Infections

Skin Infections

Wound Infections

Digestive System Infections

Blood and Lymphatic Infections

Nervous System Infections

Genitourinary Tract Infections

Microbial Ecology

Environmental Microbiology: Treatment of Water, Wastes, and Polluted Habitats

Food Microbiology

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