Chapter 01: Scope of Microbiology and Infection Control Miller: Infection Control and Management of Hazardous Materials for the Dental Team, 7th Edition MULTIPLE CHOICE 1. Who is reported to have first observed microbes? a. Pasteur b. Oliver Wendell Holmes c. Lister d. Leeuwenhoek ANS: D
Pasteur, Oliver Wendell Holmes, and Lister made other important contributions to microbiology. Leeuwenhoek first observed microbes and called them “animalcules.” PTS: 1 DIF: Recall REF: p. 2 TOP: CDA, Infection Control, Does not apply
OBJ: 2
2. What year were microbes first observed? a. 1667 b. 1880 c. 1956 d. 1975 ANS: A
Leeuwenhoek first observed microbes and called them “animalcules” in 1667, 1880, 1956, and 1975 are all too recent. PTS: 1 DIF: Recall REF: p. 2 TOP: CDA, Infection Control, Does not apply
OBJ: 2
3. Choose the microbial killing method referred to as pasteurization. a. 121C for 20 minutes b. 212F for 5 minutes c. 63C for 30 minutes d. 37C for 10 minutes ANS: C
121C for 20 minutes achieves sterilization. 212F for 5 minutes is the temperature of boiling water. 63C for 30 minutes achieves pasteurization which kills harmful microbes in liquids such as milk. 37C for 10 minutes is body temperature. PTS: 1 DIF: Application REF: p. 2 OBJ: 2 TOP: CDA, Infection Control, III.A. Instrument/device processing 4. When was the “Golden Age of Microbiology”? a. Mid to late 1600s b. Mid to late 1700s c. Mid to late 1800s
d. Mid to late 1900s ANS: C
Mid to late 1600s and mid to late 1700s were too early. Mid to late 1800s was the time when many new discoveries in microbiology were made. Mid to late 1900s was too late. PTS: 1 DIF: Recall REF: p. 2 TOP: CDA, Infection Control, Does not apply
OBJ: 2
5. What microbes are used to make vinegar, vitamins, drain cleaners, enzymes, and other
products? a. Fungi b. Viruses c. Protozoa d. Bacteria ANS: D
Fungi can make antibiotics but not these products. Viruses grow inside living cells and do not make such products. Protozoa are not very efficient in making such products. Bacteria make these and other products when they are grown in large vats. PTS: 1 DIF: Recall REF: p. 3 TOP: CDA, Infection Control, Does not apply
OBJ: 3
6. Which microbes are used to make pickles out of cucumbers? a. Bacteria or fungi b. Fungi or viruses c. Viruses or yeasts d. Bacteria of viruses ANS: A
Bacteria or fungi make certain extracellular products that change cucumbers into pickles. Viruses do not produce products that affect cucumbers. PTS: 1 DIF: Recall REF: p. 3 TOP: CDA, Infection Control, Does not apply
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7. What microbe is used to make bread dough rise? a. Bacteria b. Yeasts c. Viruses d. Protozoa ANS: B
Bacteria do not produce enough carbon dioxide (CO2) to make the dough rise. Yeasts metabolize carbohydrates to produce the gas bubbles of CO2 which causes the dough to rise. Viruses only grow inside of living cells and do not have a regular metabolism. Protozoa do not produce enough carbon dioxide (CO2) to make the dough rise. PTS: 1 DIF: Recall REF: p. 3 TOP: CDA, Infection Control, Does not apply
OBJ: 3
COMPLETION 1. Louie Pasteur and John Tyndall first recognized the use of ___________ to destroy
bacteria and resistant spores. ANS:
heat Other physical procedures were found not to be as efficient as heat for killing microbes. PTS: 1 DIF: Recall REF: p. 2 OBJ: 2 TOP: CDA, Infection Control, III.A. Instrument/device processing 2. In 1915 it was discovered that bacteria can be infected with viruses called
________________. ANS:
bacteriophages Animal viruses had been previously discovered, so they gave bacterial viruses a different name – bacteriophages – phage means “to eat.” PTS: 1 DIF: Recall REF: p. 3 TOP: CDA, Infection Control, Does not apply
OBJ: 1
3. Microbiology is the study of bacteria, molds, yeasts, protozoa, certain algae, viruses and
_________. ANS:
archaea Archaea are single cell microbes morphologically similar to bacteria, but their genes and metabolic pathways are more closely related to eukaryotes. While they may be present in the human body, there have been no clear examples of archaeal human pathogens. PTS: 1 DIF: Recall REF: p. 2 TOP: CDA, Infection Control, Does not apply
OBJ: 2
TRUE/FALSE 1. The disease of smallpox was involved in the discovery of immunizations in the 1790s by
Edward Jenner. ANS: T
Edward Jenner is credited with recognizing the concept of immunization when he realized in the 1790s that milkmaids who caught cowpox, a mild disease, were protected from the more serious disease of smallpox. PTS: 1 DIF: Recall REF: p. 2 OBJ: 2 TOP: CDA, Infection Control, I.A. Standard precautions and the prevention of disease transmission
Chapter 02: Characteristics of Microorganisms Miller: Infection Control and Management of Hazardous Materials for the Dental Team, 7th Edition MULTIPLE CHOICE 1. Under what conditions do regular bacteria, excluding Rickettsia and Chlamydia, multiply? a. In the absence of nutrients b. Only when they are inside of living cells c. When they are outside of living cells d. Only when the temperature is below 7C ANS: C
Nothing can grow in the absence of nutrients. Rickettsia and Chlamydia are the only bacteria that can grow inside living cells. Regular bacteria do not need to be inside living cells to grow. They can obtain their nutrients from the environment. Only the special bacteria called psychrophiles can grow at these low temperatures. PTS: 1 DIF: Application REF: p. 12 TOP: CDA, Infection Control, Does not apply
OBJ: 1
2. Select an environment in which viruses can multiply. a. Only in the absence of nutrients b. Only when they are inside of living cells c. Only when they are outside of living cells d. Only when the temperature is below 7C ANS: B
Nothing can grow in the absence of nutrients. Viruses need the nutrients and metabolic machinery of living cells to multiply. Viruses cannot obtain their nutrients from the environment. Only the special bacteria called psychrophiles can grow at these low temperatures. PTS: 1 DIF: Application REF: p. 14 OBJ: 2 TOP: CDA, Infection Control, I.A. Standard precautions and the prevention of disease transmission 3. Which of the following microbes is a yeast? a. Streptococcus mutans b. Trichomonas vaginalis c. Candida albicans d. Staphylococcus aureus ANS: C
Streptococcus mutans is a bacterium. Trichomonas vaginalis is a protozoan. Candida albicans can exist as a yeast which is a special fungus. Staphylococcus aureus is a bacterium. PTS: 1 DIF: Recall REF: p. 15 TOP: CDA, Infection Control, Does not apply
OBJ: 3
4. Which of the following microbes is a type of fungus? a. Influenzae b. Candida albicans c. Trichomonas vaginalis d. Streptococcus mutans ANS: B
Influenzae is a virus. Candida albicans can exist as a yeast or filamentous fungus. Trichomonas vaginalis is a protozoan. Streptococcus mutans is a bacterium. PTS: 1 DIF: Recall REF: p. 15 TOP: CDA, Infection Control, Does not apply
OBJ: 3
5. A yeast is what type of microorganism? a. Bacterium b. Fungus c. Virus d. Protozoan ANS: B
Bacteria cannot form yeast. A yeast is a special type of fungus. Viruses and protozoa cannot form yeasts. PTS: 1 DIF: Recall REF: p. 15 TOP: CDA, Infection Control, Does not apply
OBJ: 3
6. Thrush is caused by a. Candida albicans. b. Streptococcus mutans. c. Staphylococcus aureus. d. human herpesvirus 1. ANS: A
Candida albicans causes thrush (e.g., oral candidiasis or denture stomatitis) and is a fungus that may exist as a yeast cell or as a filamentous fungus (mold). Streptococcus mutans, Staphylococcus aureus, and human herpesvirus 1 do not cause thrush. PTS: 1 DIF: Recall REF: p. 15 TOP: CDA, Infection Control, Does not apply
OBJ: 3
7. Bacilli are shaped like a. spheres. b. cylinders or rods. c. curved or spiral forms. d. flat disks. ANS: B
Spheres are not bacilli. Bacilli are bacterial cells shaped like a rod or cylinder. Spirilla are curved or spiral forms. There are no microbes shaped like a flat disk. PTS: 1
DIF: Recall
REF: p. 7
OBJ: 1
TOP: CDA, Infection Control, Does not apply 8. Cocci are shaped like ____________. a. spheres b. cylinders or rods c. curved or spiral forms d. flat disks ANS: A
Spherical cells are called cocci. Rod-shaped cells are called bacilli. Curved or spiral cells are called spirilla. This is not a shape associated with bacteria. PTS: 1 DIF: Recall REF: p. 7 TOP: CDA, Infection Control, Does not apply
OBJ: 1
9. Choose the bacterial structure that controls the flow of nutrients and waste into and out of
the cell? a. Cell wall b. Flagellum c. Cytoplasmic membrane d. Capsule ANS: C
The cell wall protects the cell from being crushed. The flagellum provides locomotion. The cytoplasmic membrane has a function to regulate the entrance and exit of nutrient materials and waste products. The capsule keeps the cell from drying out and is antiphagocytic. PTS: 1 DIF: Recall TOP: CDA, Does not apply
REF: p. 8
OBJ: 1
10. Which of the following bacterial structures interferes with phagocytosis? a. Cell wall b. Flagellum c. Cytoplasmic membrane d. Capsule ANS: D
The cell wall protects the cell from being crushed. The flagellum provides locomotion. One of the functions of the cytoplasmic membrane is to regulate the entrance and exit of nutrient materials and waste products. The capsule’s “slimy” nature interferes with phagocytosis. PTS: 1 DIF: Recall REF: p. 9 TOP: CDA, Infection Control, Does not apply
OBJ: 1
11. Which of the following bacterial structures helps the cell to attach to surfaces? a. Cell wall b. Capsule c. Cytoplasmic membrane d. Fimbriae
ANS: D
The cell wall protects the cell from being crushed. The capsule keeps the cell from drying out and is antiphagocytic. One of the functions of the cytoplasmic membrane is to regulate the entrance and exit of nutrient materials and waste products. Fimbriae serve as mechanisms by which cells can attach to other cells or other environmental surfaces. PTS: 1 DIF: Recall REF: p. 9 TOP: CDA, Infection Control, Does not apply
OBJ: 1
12. The main function of the bacterial cell wall is to a. protect against drying. b. protect against crushing. c. to control the exit of wastes from the cell. d. provide the cell with locomotion. ANS: B
Protect against drying is a function of the capsule. The basic components of the cell wall (peptidoglycan) protect the cell from being crushed. Controlling the flow of nutrients and waste is a function of the cytoplasmic membrane. Providing the cell with locomotion is a function of the flagellum. PTS: 1 DIF: Recall REF: p. 8 TOP: CDA, Infection Control, Does not apply
OBJ: 1
13. The main function of bacterial fimbriae is to a. control the exit of wastes from the cell. b. protect against crushing. c. allow the cell to attach to surfaces. d. protect against drying. ANS: C
Controlling the exit of wastes from the cell is a function of the cytoplasmic membrane. Protection against crushing is a function of the cell wall. Fimbriae serve as mechanisms by which cells can attach to other cells or other environmental surfaces. Protection against drying is a function of the capsule. PTS: 1 DIF: Recall REF: p. 9 TOP: CDA, Infection Control, Does not apply
OBJ: 1
14. Choose an environment in which psychrophilic bacteria grow best. a. In the human body b. In hot water heaters c. Anywhere the temperature is 37C d. In the refrigerator ANS: D
The human body, hot water, and 37C are all too warm for the growth of psychrophiles. The refrigerator at 7C provides the optimal grow temperature for psychrophiles. PTS: 1 DIF: Application TOP: CDA, Does not apply
REF: p. 10
OBJ: 1
15. Which of the following groups of bacteria grow best inside your refrigerator? a. Psychrophiles b. Thermophils c. Mesophils d. Acidophils ANS: A
Psychrophiles are “cold-loving” and optimal growth is refrigerator temperature. Thermophils love high temperatures. Mesophils love medium (e.g., body) temperatures. Acidophils produce acids and are unrelated to temperature. PTS: 1 DIF: Recall TOP: CDA, Does not apply
REF: p. 10
OBJ: 1
16. How would prevent the growth of an obligate anaerobe? a. Adjust the pH of the environment to 7.0. b. Remove protein of the environment. c. Maintain the environmental temperature to 37C. d. Add oxygen to the environment. ANS: D
A pH of 7.0 will support the growth of most bacteria. Removing protein will not always prevent growth. Keeping the temperature at 37C will allow many bacteria to grow. Adding oxygen to the environment will prevent growth since they require low or no oxygen for growth. PTS: 1 DIF: Application REF: p. 11 TOP: CDA, Infection Control, Does not apply
OBJ: 1
17. Those bacteria that die in the presence of oxygen are called a. aerobes. b. mesophils. c. acidogens. d. anaerobes. ANS: D
Aerobes need oxygen for growth. Mesophils grow at medium temperatures and most are aerobes. Acidogens produce acids during growth and some are aerobes and some anaerobes. Anaerobes cannot tolerate oxygen. PTS: 1 DIF: Recall REF: p. 11 TOP: CDA, Infection Control, Does not apply
OBJ: 1
18. Acidogenic bacteria are noted for producing large amounts of a. acids. b. vitamins. c. proteins. d. carbohydrates. ANS: A
Acidogenic bacteria produce large amounts of acid. Vitamins may also be produced but do not relate to being acidogenic. Proteins and carbohydrates are also produced but do not relate to being acidogenic. PTS: 1 DIF: Recall REF: p. 11 TOP: CDA, Infection Control, Does not apply
OBJ: 1
19. What temperatures are the surest way to kill bacteria (or any other type of
microorganisms) in the shortest amount of time? a. Sterilizing temperatures b. Freezing temperatures c. Fluctuating temperatures d. Refrigerator temperatures ANS: A
Sterilizing temperatures such as those achieved in a steam, dry heat, or unsaturated chemical vapor sterilizer is the surest way to kill bacteria (or any other type of microorganisms) in the shortest amount of time. Freezing will not kill all microbes. Fluctuating temperatures cannot be relied upon to kill all microbes. Refrigeration will not kill all microbes. PTS: 1 DIF: Application REF: p. 14 OBJ: 1 TOP: CDA, Infection Control, III.A. Instrument/device processing 20. Anaerobes are bacteria that a. require oxygen for growth. b. grow only in the absence of oxygen. c. can multiply in the presence or absence of oxygen. d. are killed in the presence or absence of oxygen. ANS: B
Aerobes require oxygen for growth. Anaerobes cannot tolerate oxygen and only grow in its absence. Facultative anaerobes grow in the presence or absence of oxygen. PTS: 1 DIF: Recall REF: p. 11 TOP: CDA, Infection Control, Does not apply
OBJ: 1
21. Agar is a polysaccharide from seaweed that is used to a. kill bacteria. b. grow viruses. c. kill viruses. d. culture bacteria. ANS: D
Agar is not lethal to bacteria or viruses. Viruses require living cells to grow. Agar can provide a semisolid surface on which bacteria can grow if adequate nutrients are available. PTS: 1 DIF: Recall REF: p. 11 TOP: CDA, Infection Control, Does not apply
OBJ: 1
22. What environmental condition will promote the growth of an aciduric bacterium? a. Low oxygen level
b. Low nutrient level c. Low pH d. Low temperature ANS: C
Low oxygen will promote growth of anaerobes. Low nutrients restrict rather than promote bacterial growth. Low pH (usually below pH 5.5) promotes growth of aciduric bacteria. Low temperature promotes the growth of psychrophiles. PTS: 1 DIF: Application REF: p. 11 TOP: CDA, Infection Control, Does not apply
OBJ: 1
23. Which type of microbe is the most difficult to kill? a. Endospores b. Vegetative bacteria c. Viruses d. Chlamydiae ANS: A
An endospore is one most resistant forms of life against heat, drying and chemicals due to its thickened cell wall, dense cytoplasm and dormant state. Vegetative bacteria can be killed by exposing it to high heat or with chemicals. Viruses can be killed when outside the body by exposure to high heat or chemicals. Chlamydiae are a type of bacterium and can be killed by exposure to high heat or with chemicals. PTS: 1 DIF: Recall REF: p. 9 OBJ: 1 TOP: CDA, Infection Control, III.A. Instrument/device processing 24. Select the best description of a bacterial endospore a. a fungus resistant to chemicals. b. one of the most resistant forms of life to heat and chemicals. c. a virus that infects the root canal. d. a bacterium that grows at low temperatures. ANS: B
A fungus is not a bacterium. An endospore is one of the most resistant forms of life against heat, drying and chemicals due to its thickened cell wall, dense cytoplasm and dormant state. A virus is not a bacterium. A bacterium that grows at low temperatures is called a psychrophile not an endospore. PTS: 1 DIF: Recall REF: p. 9 OBJ: 1 TOP: CDA, Infection Control, III.A. Instrument/device processing 25. Some bacteria can change into special forms that are dormant and are highly resistant to
heat, chemicals, and drying? These are called a. Rickettsia. b. endospores. c. mold. d. vegetative cells. ANS: B
Rickettsia are not resistant to heat. An endospore is one most resistant forms of life against heat, drying, and chemicals due to its thickened cell wall, dense cytoplasm, and dormant state. Molds are not bacteria they are fungi. Vegetative cells and bacteria that can grow (multiply) and are not dormant. PTS: 1 DIF: Recall REF: p. 9 OBJ: 1 TOP: CDA, Infection Control, III.A. Instrument/device processing 26. Chlamydia and Rickettsia are examples of a. viruses. b. fungi. c. bacteria. d. protozoa. ANS: C
Viruses and fungi are not bacteria. Chlamydia and Rickettsia are special bacteria called obligate intracellular parasites which multiply only inside living cells. Protozoa are not bacteria. PTS: 1 DIF: Recall REF: p. 12 TOP: CDA, Infection Control, Does not apply
OBJ: 1
27. Which of the following microbes cannot be killed with antibiotics? a. Streptococcus mutans b. Staphylococcus aureus c. Human herpes virus type 1 d. Mycobacterium tuberculosis ANS: C
Streptococcus mutans and Streptococcus aureus can be killed with certain antibiotics. Human herpes virus type 1 and other viruses are not killed by antibiotics. Mycobacterium tuberculosis can be killed with certain antibiotics. PTS: 1 DIF: Recall REF: p. 15 TOP: CDA, Infection Control, Does not apply
OBJ: 1
28. Before a virus multiplies inside of our body cells, what must it do? a. Uncoat (shed its capsid) b. Assemble the capsid and nucleic acid to make a whole virus c. Adsorb (attach) to the host cell d. Kill the host cell ANS: C
Uncoating is the third step in the virus life cycle. Assembling is the fifth step in the virus life cycle. Adsorbing (attaching) to the host cell is the first step in the virus life cycle. Host cell death happens at the end of the life cycle of most viruses. PTS: 1 DIF: Recall REF: p. 15 TOP: CDA, Infection Control, Does not apply 29. Which of the following diseases is a bacterial disease? a. Influenza
OBJ: 2
b. Hepatitis B c. Mumps d. Dental caries ANS: D
Influenza, Hepatitis B, and humps are all viral diseases. Dental caries are caused by bacteria. PTS: 1 DIF: Recall REF: p. 11 OBJ: 1 TOP: CDA, Infection Control, I.A. Standard precautions and the prevention of disease transmission 30. What is the result of a virus invading a host cell? a. There is no effect on the cell. b. The virus always dies. c. The host cell always dies. d. The host cell may die or be changed. ANS: D
If a virus invades a cell there is always some effect. The virus may survive and kill or damage the cell. Sometimes the host cell survives with minor damage or permanent changes. Depending upon the virus, the cell may be killed or it may survive with minor damage. PTS: 1 DIF: Recall REF: p. 15 OBJ: 2 TOP: CDA, Infection Control, I.A. Standard precautions and the prevention of disease transmission 31. Viruses cause diseases in humans because they a. produce exotoxins. b. produce endotoxins. c. invade and kill or damage cells in our body. d. “swim” away from phagocytes using their flagella. ANS: C
Exotoxins are involved in some bacterial or fungal diseases. Endotoxins are involved in some bacterial diseases. Viruses cause disease by entering and multiplying in our body cells and killing or changing them. Viruses do not have flagella. PTS: 1 DIF: Application REF: p. 15 OBJ: 2 TOP: CDA, Infection Control, I.A. Standard precautions and the prevention of disease transmission 32. During the life cycle of a virus, what is the next step after the virus attaches to the host
cell? a. Uncoating b. Release c. Replication d. Enters the cell ANS: D
Uncoating is the third step in the life cycle of a virus. Release is the sixth and final step in the life cycle of a virus. Replication is the fourth step in the life cycle of a virus. In the second step of the life cycle of a virus (penetration), the virus enters the host cell. PTS: 1 DIF: Application REF: p. 15 TOP: CDA, Infection Control, Does not apply
OBJ: 2
33. The genes of a virus are in the a. capsid. b. nucleic acid core. c. envelope. d. capsid and envelope. ANS: B
The capsid is the protein coating of virus that protects the nucleic acid core and determines the shape of the virus. The nucleic acid core contains the DNA or RNA genes of a virus. The envelope is the outer lipid-rich layer found in some viruses that is derived from the host cell membrane on release of the virus from the host cell. The capsid and envelope is referring to the outer protein coating (capsid) and the outer lipid-rich layer found in some viruses (envelope). PTS: 1 DIF: Recall REF: p. 14 TOP: CDA, Infection Control, Does not apply
OBJ: 2
34. What is the final product from the bacterial fermentation of sugar (e.g., glucose)? a. Nucleic acid b. Lactic acid c. Hydrochloric acid d. Pyruvic acid ANS: B
Nucleic acid is DNA or RNA neither of which are direct products of fermentation. Lactic acid is the final product. Hydrochloric acid is stomach acid. Pyruvic acid is the second to the last fermentation product. PTS: 1 DIF: Recall REF: p. 13 TOP: CDA, Infection Control, Does not apply
OBJ: 1
35. Which of the following substances is a component of some bacterial outer membranes and
when released in the human body contributes to the causes of periodontal disease? a. Lysozyme b. Mesosome c. Capsid d. Endotoxin ANS: D
Lysozyme is an enzyme in saliva produced by the human body. Mesosomes are part of the bacterial structure but are not directly involved in periodontal diseases. The capsid is the protein coat of viruses. The action of endotoxin is thought to play a role in many infectious diseases, including periodontal diseases. PTS: 1
DIF: Application
REF: p. 9
OBJ: 1
TOP: CDA, Infection Control, Does not apply 36. Agents that prevent bacterial growth without killing them are referred to as a. bacteriostatic agents. b. sterilant agents. c. disinfectant agents. d. nucleic acid agents. ANS: A
Bacteriostatic agents prevent or slow down bacterial growth which resumes when, and if, the agents are removed or degraded. Sterilant and disinfectant agents kill bacteria. Nucleic acid agents do not directly affect the growth of bacteria. PTS: 1 DIF: Recall REF: p. 13 OBJ: 1 TOP: CDA, Infection Control, II.A. Prevent cross-contamination during procedures 37. Colony-forming-units (CFU) are defined as a. measurements of the diameter of colonies that develop on an agar medium. b. individual bacterial cells or a small group of cells each of which can form a colony
on agar media. c. units used to estimate the distance a bacterial cell can move away from its colony on agar media. d. highly resistant forms of certain bacteria. ANS: B
Colony diameter is measured in millimeters. One or a small number of bacterial cells deposited on an appropriate agar medium will develop into a single colony (clone) of cells and be referred to as a colony-forming unit. The distance a bacterial cell can move away from its colony on agar media is seldom measured but is expressed in millimeters. Highly resistant forms of bacteria are referred to as endospores. PTS: 1 DIF: Recall REF: p. 12 OBJ: 1 TOP: CDA, Infection Control, II.A. Prevent cross-contamination during procedures 38. How are bacterial spores important in dental infection control? a. They cause periodontal disease. b. They are used to monitor surface disinfection. c. They are used to test the functioning and use of sterilizers. d. They cause thrush. ANS: C
Periodontal diseases are caused by nonspore-forming bacteria. There is not an easy test for surface disinfection. Since bacterial spores are highly resistant to heat, they are used to monitor heat sterilization in steam, dry heat and other sterilizers. PTS: 1 DIF: Recall REF: p. 9 OBJ: 1 TOP: CDA, Infection Control, III.B. Instrument/device processing 39. Which of the following bacteria are important in metabolizing sugar to acids that cause
dental caries? a. Geobacillus stearothermophilus b. Bacillus atrophaeus
c. Clostridium sporogenes d. Streptococcus mutans ANS: D
Geobacillus stearothermophilus is a spore-former use to monitor steam sterilizers. Bacillus atrophaeus is a spore-former use to monitor dry heat sterilizers. Clostridium sporogenes is a spore-former that is used to test the effectiveness of liquid sterilants. Streptococcus mutans forms plaque and metabolizes dietary sugar to acids causing demineralization of tooth enamel. PTS: 1 DIF: Recall REF: p. 13 TOP: CDA, Infection Control, Does not apply
OBJ: 1
40. Which of the following represents the pH values of acid? a. 0 to 7 b. 7 to 14 c. 8 to 10 d. 10 to 12 ANS: A
Acids have a pH from 0 to 7, 7 to 14, 8 to 10, and 10 to 12 are all alkaline. PTS: 1 DIF: Recall REF: p. 11 TOP: CDA, Infection Control, Does not apply
OBJ: 1
41. mRNA is formed from DNA through a process called a. transformation. b. transcription. c. transmission. d. transduction. ANS: B
Transformation is where a bacterial cell takes up extracellular DNA released from other bacteria. Transmission is a general term for spread. Transduction is where viruses transfer genes from one bacterial cell to another. PTS: 1 DIF: Recall REF: p. 13 OBJ: 1 TOP: CDA, Infection Control, I.A. Standard precautions and the prevention of disease transmission 42. The function of mRNA is to associate with ribosomes and a. link amino acids to from proteins. b. transfer genes through the sex pilus to another bacterial cell. c. exit the cell for uptake up by other cells. d. bind to a virus that exits the cell, infects other cell transmitting the nucleic acid to
the new cell. ANS: A
DNA is transferred through the sex pilus. DNA can exit the cell for uptake by other cells. DNA binds to viruses for transfer to other cells. PTS: 1
DIF: Application
REF: p. 13
OBJ: 1
TOP: CDA, Infection Control, I.A. Standard precautions and the prevention of disease transmission 43. What emerging fungus has caused bloodstream, wound, oral and ear infections? a. Bacillus subtilis b. Staphylococcus aureus c. Mycobacterium tuberculosis d. Candida auris ANS: D
Bacillus subtilis, Staphylococcus aureus, and Mycobacterium tuberculosis are bacteria. PTS: 1 DIF: Recall REF: p. 15 OBJ: 3 TOP: CDA, Infection Control, I.A. Standard precautions and the prevention of disease transmission COMPLETION 1. For growth all bacteria need the proper nutrients, temperature, pH, atmosphere and
_________. ANS:
water Water is essential for all life forms. PTS: 1 DIF: Application REF: p. 11 TOP: CDA, Infection Control, Does not apply
OBJ: 1
TRUE/FALSE 1. Bacteria are larger than viruses. ANS: T
Bacteria average about 1.0 m in diameter, and human viruses are smaller than bacteria, ranging from 0.02 to 0.3 m. PTS: 1 DIF: Recall REF: p. 14 TOP: CDA, Infection Control, Does not apply
OBJ: 2
2. Bacterial growth is defined as an increase in cell numbers. ANS: T
When bacteria grow they double their numbers with each generation. PTS: 1 DIF: Recall REF: p. 10 TOP: CDA, Infection Control, Does not apply 3. Human virus are smaller than bacteria. ANS: T
OBJ: 1
Bacteria average 1.0 m in diameter. Human viruses are smaller than bacteria, ranging from 0.02 to 0.3. PTS: 1 DIF: Recall REF: p. 14 TOP: CDA, Infection Control, Does not apply
OBJ: 2
4. If bacteria grow in a broth culture, the broth remains clear. ANS: F
If bacteria grow in broth culture, the broth becomes turbid (cloudy). PTS: 1 DIF: Recall REF: p. 12 OBJ: 2 TOP: CDA, Infection Control, III.B. Instrument/device processing 5. Unlike bacterial diseases, most viral diseases cannot be successfully treated. ANS: T
Because viruses use the metabolic machinery of the host cell to replicate, chemicals such as antibiotics used against bacteria may damage the host cells and cannot be used to treat viral diseases. PTS: 1 DIF: Recall REF: p. 15 OBJ: 2 TOP: CDA, Infection Control, I.A. Standard precautions and the prevention of disease transmission
Chapter 03: Development of Infectious Diseases Miller: Infection Control and Management of Hazardous Materials for the Dental Team, 7th Edition MULTIPLE CHOICE 1. Microbes that are usually harmless but can cause disease under certain conditions are
called a. opportunistic pathogens. b. toxigenic pathogens. c. endogenous pathogens. d. exogenous pathogens. ANS: A
Opportunistic pathogens cause diseases only when given a special opportunity to enter deeper tissues of the body or to accumulate to levels that can harm the body. Toxigenic pathogens are caused by toxins released by a bacterium or fungus. Endogenous pathogens are caused by microbes that already exist within the body. Exogenous pathogens are caused by microbes that enter the body from the outside. PTS: 1 DIF: Recall REF: p. 17 TOP: CDA, Infection Control, Does not apply
OBJ: 4
2. Microbes that cause disease by producing a toxin are called a. opportunistic pathogens. b. toxigenic pathogens. c. endogenous pathogens. d. exogenous pathogens. ANS: B
Opportunistic pathogens cause diseases only when given a special opportunity to enter deeper tissues of the body or to accumulate to levels that can harm the body. Toxigenic pathogens are caused by toxins released by a bacterium or fungus. Endogenous pathogens are caused by microbes that already exist within the body. Exogenous pathogens are caused by microbes that enter the body from the outside. PTS: 1 DIF: Recall REF: p. 17 TOP: CDA, Infection Control, Does not apply
OBJ: 3
3. Members of the normal body microbiota that can cause disease are called a. obligate intracellular parasite. b. toxigenic pathogens. c. endogenous pathogens. d. exogenous pathogens. ANS: C
Obligate intracellular parasites (e.g., all viruses and some special bacteria) cause diseases by invading body cells. Toxigenic pathogens are caused by toxins released by a bacterium or fungus. Endogenous pathogens are caused by microbes that already exist within the body. Exogenous pathogens are caused by microbes that enter the body from the outside.
PTS: 1 DIF: Recall REF: p. 17 TOP: CDA, Infection Control, Does not apply
OBJ: 3
4. The difference between an infection and an infectious disease is that an a. infection never causes an infectious disease. b. infection comes after the infectious disease has already started. c. infectious disease is an infection that causes damage to the body. d. infectious disease and an infection can never involve the same microbe. ANS: C
Some infections can lead to disease. Infection comes before the infectious disease starts. An infection does not always indicate disease, but disease (damage to the body) seldom results without infection (the exception is toxigenic diseases). Infectious disease and an infection can involve the same microbe. PTS: 1 DIF: Comprehension REF: p. 19 OBJ: 1 TOP: CDA, Infection Control, I.A. Standard precautions and the prevention of disease transmission 5. That period of an infectious disease between the initial infection and the time when the
first symptoms occur is called the a. convalescent stage. b. acute stage. c. prodromal stage. d. incubation stage. ANS: D
Convalescent stage is the recovery phase. Acute stage is when the symptoms are at or near maximum levels. Prodromal stage is the early symptoms stage. Incubation stage is the time between infection and appearance of signs/symptoms. PTS: 1 DIF: Recall REF: p. 18 OBJ: 1 TOP: CDA, Infection Control, I.A. Standard precautions and the prevention of disease transmission 6. That period of an infectious disease when the symptoms are at or near the maximum level
is called the a. convalescent stage. b. acute stage. c. prodromal stage. d. incubation stage. ANS: B
Convalescent stage is the recovery phase. Acute stage is when the symptoms are at or near maximum levels. Prodromal stage is the early symptoms stage. Incubation stage is the time between infection and appearance of signs/symptoms. PTS: 1 DIF: Recall REF: p. 18 OBJ: 1 TOP: CDA, Infection Control, I.A. Standard precautions and the prevention of disease transmission
7. That period of an infectious disease when the symptoms are declining is called the a. convalescent stage. b. acute stage. c. prodromal stage. d. incubation stage. ANS: A
Convalescent stage is the recovery phase in which symptoms are waning. Acute stage is when the symptoms are at or near maximum levels. Prodromal stage is the early symptoms stage. Incubation stage is the time between infection and appearance of signs/symptoms. PTS: 1 DIF: Recall REF: p. 18 OBJ: 1 TOP: CDA, Infection Control, I.A. Standard precautions and the prevention of disease transmission 8. An asymptomatic carrier can be in which of the following stages of an infectious disease? a. Convalescent stage b. Acute stage c. Prodromal stage d. Incubation stage ANS: D
Convalescent stage is the recovery phase in which symptoms are waning. Acute stage is when the symptoms are at or near maximum levels. Prodromal stage is the early symptoms stage. Incubation stage is the time between infection and appearance of signs/symptoms. PTS: 1 DIF: Recall REF: p. 18 OBJ: 1 TOP: CDA, Infection Control, I.A. Standard precautions and the prevention of disease transmission 9. The mode of microbe transmission that involves touching the patient’s teeth while not
wearing gloves is called a. direct contact. b. indirect contact. c. droplet infection. d. airborne infection. ANS: A
Direct contact is person-to-person body contact. Indirect contact is contact with an item (e.g., an instrument) that was contaminated with another patient’s microbes. Droplet infection involves contact with larger droplets in sprays or spatter containing microbes. Airborne infection involves contact with the smaller droplet nuclei (e.g., dental aerosols) in sprays or spatter. PTS: 1 DIF: Application REF: p. 19 OBJ: 1 TOP: CDA, Infection Control, I.D. Standard precautions and the prevention of disease transmission | CDA, Infection Control, II.A. Prevent cross-contamination during procedures 10. The mode of microbe transmission that involves a needlestick is called a. direct contact. b. indirect contact.
c. droplet infection. d. airborne infection. ANS: B
Direct contact is person-to-person body contact. Indirect contact is contact with an item (e.g., an instrument needle) that was contaminated with another patient’s microbes. Droplet infection involves contact with larger droplets in sprays or spatter containing microbes. Airborne infection involves contact with the smaller droplet nuclei (e.g., dental aerosols) in sprays or spatter. PTS: 1 DIF: Application REF: p. 19 OBJ: 1 TOP: CDA, Infection Control, IV.A. Occupational safety/administrative protocols 11. The mode of microbe transmission that involves small droplet nuclei such as those
generated from dental aerosols is called a. direct contact. b. indirect contact. c. droplet infection. d. airborne infection. ANS: D
Direct contact is person-to-person body contact. Indirect contact is contact with an item (e.g., an instrument) that was contaminated with another patient’s microbes. Droplet infection involves contact with larger droplets in sprays or spatter containing microbes. Airborne infection involves contact with the smaller droplet nuclei (e.g., dental aerosols) in sprays or spatter. PTS: 1 DIF: Application REF: p. 19 OBJ: 1 TOP: CDA, Infection Control, I.E. Standard precautions and the prevention of disease transmission 12. Which of the following best describes antibodies? a. Chemicals produced by bacteria or fungi that can kill other microorganisms. b. Proteins that are released from bacteria to degrade large substances to smaller
chemicals that can be taken into the cell and used for growth. c. Special proteins produced in our body in the presence of antigens that aid in
destroying those antigens or help in their removal from the body. d. A part of the cell wall of gram-negative bacteria that enhances inflammation when
released from the bacterial cell. ANS: C
Chemicals produced by bacteria or fungi that can kill other microorganisms are referred to as antibiotics. Extracellular enzymes are proteins that are released from bacteria to degrade large substances to smaller chemicals that can be taken into the cell and used for growth. Antibodies are special proteins produced in our body in response to the presence of antigens, and they aid in destroying those antigens or help in their removal from the body. An endotoxin is part of the cell wall of gram-negative bacteria that enhances inflammation when released from the bacterial cell. PTS: 1 DIF: Recall REF: p. 23 OBJ: 5 TOP: CDA, Infection Control, I.A. Standard precautions and the prevention of disease transmission
13. Which of the following best describes extracellular enzymes? a. Chemicals produced by bacteria or fungi that can kill other microorganisms. b. Proteins that are released from bacteria to degrade large substances to smaller
chemicals that can be taken into the cell and used for growth. c. Special proteins produced in our body in the presence of antigens that aid in
destroying those antigens or help in their removal from the body. d. A part of the cell wall of gram-negative bacteria that enhances inflammation when
released from the bacterial cell. ANS: B
Chemicals produced by bacteria or fungi that can kill other microorganisms are referred to as antibiotics. Extracellular enzymes are proteins that are released from bacteria to degrade large substances to smaller chemicals that can be taken into the cell and used for growth. If these macromolecules are parts of host cell surfaces or are tissue components, this process can kill cells or damage the tissue. Antibodies are special proteins produced in our body in response to the presence of antigens, and they aid in destroying those antigens or help in their removal from the body. An endotoxin is part of the cell wall of gram-negative bacteria that enhances inflammation when released from the bacterial cell. PTS: 1 DIF: Recall REF: p. 21 TOP: CDA, Infection Control, Does not apply
OBJ: 3
14. The major source of disease agents in the dental office is a. dental unit water. b. the mouth of the patient. c. air. d. dust. ANS: B
Dental unit water contains microbes but not as many potential pathogens as patients’ mouths. Microbes in patient’s mouths include those that may be present in saliva, respiratory secretions, and blood that may enter the mouth during dental care. Air and dust contain microbes but not as many potential pathogens as patient’s mouths. PTS: 1 DIF: Recall REF: p. 17 OBJ: 1 TOP: CDA, Infection Control, II.A. Prevent cross-contamination during procedures 15. Special proteins that are made by the body after a microbe invades the body are called a. antigens. b. acids. c. antiseptics. d. antibodies. ANS: D
Antigens are cells, microbes or substances that invade the body and activate the immune response. Acids are not proteins. Antiseptics are germicides applied to the body. Antibodies are proteins produced by the body after an antigen (e.g., a microbe) invades the body. PTS: 1 DIF: Recall REF: p. 23 OBJ: 3 TOP: CDA, Infection Control, I.A. Standard precautions and the prevention of disease