Microbiology: Control growth Flashcards

The multidrug resistant pumps in many bacterial cell membranes function by

Bacterial chromosomal mutations
Synthesis of enzymes that alter drug structure
Removing the drug from the cell when it enters
Alteration of drug receptors on cell targets

The cellular basis for bacterial resistance to antimicrobials include

Bacterial chromosomal mutations
Synthesis of enzymes that alter drug structure
Prevention of drug entry into the cell
Alteration of drug receptors on cell targets
All of the choices are correct

Antiviral drugs that target reverse transcriptase would be used to treat

Influenza A virus
HIV
Herpes zoster virus
Respiratory syncytial virus
Hepatitis C virus

An antiviral that is a guanine analog would have an antiviral mode of action that

Blocks penetration
Blocks transcription and translation
Inhibits DNA synthesis
Blocks maturation
Bonds to ergosterol in the cell membrane

1. Commercial products containing which types of chemicals are more effective at killing microorganisms?
Bacteriostatic
Lead
Bacteriocidal
Carbohydrate
None of these are correct

2.Using toilet bowl cleaner and nonionizing radiation to inanimate surfaces only removes or kills vegetative bacteria. The term that best describes this action is _________.
Disinfection
Sterilization
Antisepsis
Degermation
None of these are correct

3. Which of these metals have antimicrobial properties associated with them?
Silver
Gold
Aluminum
Tin
Both A and B are correct

4.Which of the following types of agents targets protein conformation?
Alcohol
Hydrogen peroxide
Ultraviolet light
Detergents
Crystal violet

5.All of the following are correct about the autoclave, except _________.
Sterilization is achieved when steam condenses against the objects in the chamber and raises their temperatures
It is effective for sterilizing powders, oils, and waxy substances
It is the temperature that kills the microbes, not the pressure itself
The duration of the process depends on how full the chamber is
It is important not to overload the chamber

6.Which common hospital pathogen is able to grow abundantly in soap dishes?
Salmonella
Mycobacteria tuberculosis
Escherichia coli
Hemophilus influenza
Pseudomonas

7.Historically, which of the following was instilled into the eyes of newborn infants to prevent gonococcal infections?
Mercurochrome
Triclosan
Silver nitrate
Phenol
Formaldehyde

8.All of the following are methods of disinfection or sterilization, except _________.
Lyophilization
Gamma radiation
Ethanol
Dry oven
Triclosan

9.All of the following are benefits of food irradiation, except _________.
It can inhibit the sprouting of white potatoes
It makes the food less nutritious
It can kill bacterial pathogens on the food
In can reduce the number of food-borne deaths each year
It can kill insects on the food

10. All of the following are correct about food irradiation, except _________.
The World Health Organization does not endorse this process
No irradiated food can be sold without clear labeling
food is not made radioactive by the process
it is approved in the U.S. for beef, chicken, and pork
it can lead to a longer shelf life for the irradiated food

11.Which of the following is officially accepted as a sterilant and high-level disinfectant?
Cresol
Glutaraldehyde
Silver nitrate
Benzalkonium chloride
Triclosan

12.Which of the following chemicals is a disinfectant for soft contact lenses?
Hypochlorite
Hydrogen peroxide
Hexachlorophene
Glutaraldehyde
Alcohol

13.Which of the following is being used to replace hypochlorites in treating water because of the possibility of cancer-causing substances being produced?
Hydrogen peroxide
Chloramines
Sodium iodide
Quaternary ammonium compounds
Fluorine

14.The sterilizing gas used in a special chamber is _________.
Glutaraldehyde
Iodophor
Chlorine dioxide
Ethylene oxide
Formaldehyde

15.Alcohols _________.
At 50% or higher concentrations dissolve cell membrane lipids
Denature proteins when in a 50-95% solution
Are used to disinfect items by soaking
Are skin degerming agents
All of the choices are correct

16.Which control method would not be a suitable choice for killing Mycobacteria in a capped culture tube?
121oC at 15 psi for 15 minutes
Ultraviolet (germicidal) light
160oC for 2 hours
Gamma rays
All of the choices are correct

17.The easiest microbial forms to kill or inhibit are _________.
Protozoan cysts
Endospores
Vegetative bacteria and fungi
Mycobacterium and Staphylococcus
Naked viruses

18.HEPA filters are used to remove microbes from _________.
Human tissues
Liquids
Air
Medical instruments
All of the choices are correct

19.Disinfection of beverages, such as apple juice, milk, and wine, is optimally achieved by _________.
Pasteurization
Chlorination
Moist heat autoclave
Boiling water
Filtration

20.The shortest time required to kill all the microbes in a sample at a specified temperature is called the __________.
Sporicidal time
Death phase point
Thermal death point (TDP)
Thermal death time (TDT)
None of the choices are correct

21.Dry heat _________.
Is used in devices called autoclaves
Is less efficient than moist heat
Includes tyndallization
Cannot sterilize
Will sterilize at 121oC for 15 minutes

22.Sterilization is achieved by _________.
Flash pasteurization
Steam autoclave
Boiling water
Hot water
All of the choices are correct

23.Scrubbing or immersing the skin in chemicals to reduce the numbers of microbes on the skin is _________.
Sanitization
Degermation
Sterilization
Disinfection
Antisepsis

24.The use of chemical agents directly on exposed body surfaces to destroy or inhibit vegetative pathogens is _________.
Sterilization
Degermation
Antisepsis
Sanitization
Disinfection

25.Microbiological contaminants are best described as _________.
Vegetative microbes present on or in a substance
Any and all microbes present on or in a substance
Pathogenic microbes present on or in a substance
Unwanted microbes present on or in a substance
None of the choices are correct

26.Which of the following antimicrobials is contraindicated for children due to permanent tooth discoloration?
Penicillin G
Erythomycin
Gentamicin
Vancomycin
Tetracycline

27.Which organ is responsible for metabolizing and detoxifying foreign chemicals in the blood, including drugs?
Kidneys
Liver
Stomach
Gall bladder
Spleen

28.A nurse preparing a section of skin for an injection is an example of __________.
sanitization
disinfection
sterilization
degerming

29.the eradication of all organisms including bacterial endospores and viruses (although not prions) in or on an object.

disinfection.

sanitization

sterilization

degerming

30.the removal of microbes from a surface by scrubbing

disinfection

sanitization

sterilization

degerming

31.The process of filtration is a(n) _______________.
antiseptic procedure
ineffective method for removing microbes
sterilizing method
disinfectant method
sanitization method

32.Damage to the cell wall will adversely affect a bacterial cell by making it more susceptible to __________.
alcohols
radiation
osmotic pressure
high temperature

33.The process of filtration is a(n) _______________.
antiseptic procedure
ineffective method for removing microbes
sterilizing method
disinfectant method
sanitization method

34-the process of disinfecting surfaces and utensils used by the public

disinfection

sanitization

sterilization

degerming

35.the use of physical or chemical agents to inhibit or destroy microorganisms on inanimate objects

disinfection

sanitization

sterilization

degerming

36.Which of the following is not a mode of action of an antiviral?
Inhibit DNA synthesis
Bond to ergosterol in the cell membrane
Block transcription and translation
Block penetration
Block mutation

37.There are fewer antifungal, antiprotozoan, and antihelminth drugs compared to antibacterial drugs because these organisms _________.
Do not cause many human infections
Are parasites found inside human cells
Are not affected by antimicrobics
Are so similar to human cells that selective drug toxicity is difficult to achieve
Have fewer target sites compared to bacteria

38.Antibiotics are derived from all the following, except _________.
Staphylococcus
Bacillus
Streptomyces
Cephalosporium
Penicillium

39.Drug-resistant population of microbes arise when _________.
Resistant cells become numerous in a population due to their greater vigor
Exposure to drugs selectively kills sensitive cells allowing overgrowth of resistant cells
Synergy between medications occurs
Exposure to drugs causes mutation that produce resistance
That patient becomes immune to the drug

40.Bacterial DNA replication requires the enzyme gyrase, but eukaryotic replication does not. Ciprofloxacin (“Cipro”) inhibits gyrase activity. This is an example of _________.
Use of an analog
An antimetabolite
Synergism
Selective toxicity
Antimicrobial resistance

41.Synthetic antimicrobials that block protein synthesis by binding to the mRNA are _________.
Macrolides
Aminoglycosides
Nucleic acid analogs
Antisense nucleic acids
Beta-lactams

42.Most drugs that inhibit the synthesis of the cell wall act by _________.
Disrupting the formation of the mycolic acid layer of the cell wall
Preventing the formation of the alanine-alanine bridges
Preventing the cross-linkage of NAM subunits
Blocking the secretion of cell wall molecules from the cytoplasm
Prevent the formation of β-lactamases

43.The CDC issued alerts about a bacterial strain known as NDM1 (New Delhi metalo-lactamase 1). What type of antibiotic resistance is indicated by the name?
Removal of the drug via a pump
Alteration of the target of the drug
Change in the permeability of the drug
Overproduction of an enzyme in a key metabolic pathway
Inactivation of the drug

44.In the compound lamivudine, an –SH group replaces an –OH group found in cytosine. When used as a medication it will _________.
Disrupt lipid membrane structure
Disrupt membrane structure
Interfere with nucleic acid synthesis
Interfere with cell wall synthesis
Interfere with protein synthesis

45.The first synthetic antimicrobial widely available for treatment of infections _________
Was an attachment antagonist
Disrupted cytoplasmic membranes
Interfered with bacterial cell wall synthesis
Was a nucleotide analog
Was an antimetabolite

46.Which of the following is a primary advantage of semisynthetic drugs?
They work faster
They are not readily absorbed, so they persist longer
They must be administered intravenously
They are less stable and consequently have fewer side effects
They have a broader spectrum of action

47.Beta-lactam antibiotics have an effect on which of the following types of cells?
Bacterial cells
Virus-infected cells
Animal cells
Fungal cells
Both animal and fungal cells

48.An antimicrobial that inhibits cell wall synthesis will result in which of the following?
Cells cannot attach to their hosts
The replication of cell, including cancer cells slows down.
Ribosomes lose their function
Cells become more susceptible to osmotic pressure
The sterols in the cell wall become nonfunctional

49Which mode of antibiotic activity is the most selective target for antibiotics since it will not affect eukaryotic cells?

Inhibition of transcription
Inhibition of cell wall synthesis
Inhibition of translation

Inhibition of DNA replication

Injury to the plasma membrane

50.Which antibiotic pictured is not recommended for children due to possible discolorations of their teeth?

Penicillin
Amphotericin B
Tetracycline
Chloramphenicol

51.A chemical that kills gram-positive bacteria and gram-negative bacteria is described as:

selectively toxic.
inhibitory.
broad spectrum.
narrow spectrum.

52.A drug that inhibits peptidoglycan synthesis is:

antibacterial.
antifungal.
antiprotozoal.
antiviral.

53.An antiviral that is a guanine analog would have an antiviral mode of action that
blocks penetration.
blocks transcription and translation.
inhibits DNA synthesis.
blocks maturation.
bonds to ergosterol in the cell membrane.

54.The multidrug resistant pumps in many bacterial cell membranes function by
bacterial chromosomal mutations.
synthesis of enzymes that alter drug structure.
removing the drug from the cell when it enters.
alteration of drug receptors on cell targets.

55.Each of the following result in drug resistance except
drug pumped out of the cell.
drug used as a nutrient by the cell.
drug binding site altered.
drug inactivated.
drug blocked from entering cell.

56.Each of the following is a mechanism for drug resistance transfer between microorganisms except
transposons.
R-plasmids.
conjugation.
mutation.

57.Nutrients that encourage the growth of beneficial microbes in the intestines are known as

prebiotics.

probiotics.
lantibiotics.
phytobiotics.

58.Which therapeutic index value would be the drug of choice?
20
10
1
0.1

59.Important characteristics of antimicrobial drugs include
low toxicity for human tissues.
high toxicity against microbial cells.
do not cause serious side effects in humans.
stable and soluble in body tissues and fluids.
All of the choices are correct.

60.Selective toxicity refers to
damage to pathogenic organisms.
damage to prokaryotic cell membranes.
damage to the target organisms but not host cells.
damage to nucleic acids.

61.Drugs that insert on the _____ ribosomal subunit prevent peptide bond formation or inhibit translocation of the subunit during translation.
30S
40S
50S

60S

62. Drugs that act by mimicking the normal substrate of an enzyme, thereby blocking its active
site, are called
inhibitors.
blockers.
competitive inhibitors.
noncompetitive inhibitors.

63.What type of chemical will allow some bacteria to be resistant to many penicillins?
synercid
penicillinase
aztreonam
clavulanic acid

64.Antibiotics that disrupt bacterial ribosomes can also affect

eukaryotic large ribosomal subunit.

eukaryotic small ribosomal subunit.

ribosomal RNA.

eukaryotic mitochondrial ribosomes.

65.Drugs that act by mimicking the normal substrate of an enzyme, thereby blocking its active site, are called

______.

inhibitors

blockers

competitive inhibitors

noncompetitive inhibitors

66-Which of the following is the third stage of a disease?

Period of convalescence
Incubation period
Period of decline
Prodromal period
Period of illness

67.Which of these disease stages is most likely to be altered in length if the number of infecting organisms at the start of the infection is very high?

Period of convalescence
Prodromal period
Period of illness
Incubation period
Period of decline

68.Microorganisms that typically colonize a host without causing disease are referred to as the __________.

pathogens
opportunistic pathogens
normal microbiota
transient microbes

69. occurs when someone come into direct contact with the infectous lesion or infected body fluid.

70.involves the transfer organisms to a person through handling of contaminated instruments and then touching face, eyes, or mouth.

71. spread of disease through moisture containing bacteria or virus.

ex: coughing through the air

72.What occurs during vehicle transmission?

73.Vehicle Transmission, how does media transmit the pathogen?

74.What is a biological vector?

75.Contact Transmission, What is the distance in which a droplet nuclei would travel to achieve the spread of disease?

76. A disease which develops rapidly but lasts only a short time, like influenza

77. A disease which develops slowly, & the symptoms may be less severe but it is likely to continue or recur for periods with continuous shedding of the pathogen. likeGlandular fever, Hepatitis B

78.The pathogen remains inactive for a time but may be re-activated under certain conditions. Herpes virus
(cold sores)

79. The infection produces an immune response without recognisable symptoms. Rubella (German measles)

80. "contagious" an INFECTIOUS disease that is readily transmitted from one individual to another..either directly or indirectly. infectious disease transmissible from one human to another (ex: gonorrhea)

81. What is a noncommunicable disease?

82. - Primary infection:

83. Localized infection:

84 - Systemic infection:

85. Mixed infection (polymicrobial):

86. Secondary infection :

87.The reservoir of infection for botulism and tetanus is
humans.
soil.
water.
animals.
soil AND water.

88.The popular name for tetanus is
hydrophobia.
lockjaw.
whooping cough.
consumption.

89.The exotoxin produced by C. tetani is
tetanoxin.
exotetanus.
tetanospasmin.
endospasmin.

90.The disease that involves the muscles and often manifests itself first with spasms of the jaw muscles is
polio.
rabies.
tetanus.
gastritis.

91.Tetanus prevents the release of neurotransmitters from
muscle cells.
excitatory neurons.
inhibitory neurons.
tetano cells.

92. The normal habitat of Clostridium tetani is
humans.
animals.
plants.
soil and dust.

93.Production of a neurotoxin that binds to target sites on spinal cord neurons responsible for inhibiting skeletal muscle contraction is a characteristic of
Clostridium botulinum.
Clostridium perfringens.
Clostridium difficile.
Clostridium tetani.

94.What does Polio invade?

95.What is polio caused by?

96.Which of the following diseases is NOT caused by an organism that enters the body through the gastrointestinal tract?
leprosy
polio
infant botulism
adult listeriosis