MCB 100 Final Exam
Classical pasteurization heats the fluid to about ___ deg С for a time of about___
63/30 minutes.
An antimicrobial that inhibits bacterial cell wall synthesis will result in which of the following?
Bacterial cells become more susceptible to osmotic pressure.
Which of the following is an alternative strategy for identifying new drug targets?
Comparative genomics
Quinolones and fluoroquinolones act against what bacterial target?
DNA gyrase
If an unimmunized person has possibly been exposed to the bacterium that causes tetanus, the patient is given both active and passive immune treatment against tetanus. Why are they both necessary?
During the time it takes for the patient's body to develop an active immune response, the passive immunity neutralizes any free-floating tetanus toxin.
Some scientists are considering using passive immunization as a primary means to control infections by bacteria that are so resistant to antibiotics that they are currently untreatable. Would this work?
* ASK * Yes, passive immunization would enhance clearance of the resistant bacteria via the complement cascade.? options: No, infections with highly resistant bacteria are untreatable by all means. No, passive immunization would not be any more effective for resistant bacteria than sensitive bacteria. No, passive immunization has nothing to do with antibiotic resistance. Yes, passive immunization would enhance clearance of the resistant bacteria via the complement cascade. Yes, passive immunization would enhance the effect of the antibiotics by resensitizing the resistant bacteria.
What is the largest attraction for Pharma to stick with known antibiotics and modifying their structures, rather than looking for new antibiotic targets or drug candidates?
* ASK * the options are A. Pharma prefers drugs already known to have few or no side effects. B. Pharma prefers drugs for which there already is plenty of data, so approval process is faster. C. Pharma prefers drugs with broad-spectrum that have multiple targets, so it is cheaper. The answer is NOT: All, C, B and C, or A and C
Vaccine adverse events are expected to occur with a certain frequency. An event that occurs in 2 out of a 10,000 persons is regarded as common.
F
Which of the following situations might yield a false positive result?
Failure to wash away and remove the unattached enzyme-linked antibody.
Determine which of the following is true or false and then select the correct series of answers: DNA vaccines are bacterial plasmids that contain cloned DNA with an antigen of interest, but unlike attenuated vaccines, there is no chance of infection when injected into animals. Recombinant vaccines can be developed from synthetic peptides, proteins, lipoproteins or glycoproteins. A toxoid is an attenuated form of a toxin that retains both its antigenicity and toxicity.
TTF
Why are proteins added to the wells at the beginning of an ELISA?
The proteins block any accidental adherence of serum antibodies to the wells.
Using a direct fluorescent antibody test, a patient's brain tissue sample is flooded with tagged antibody to rabies and it fluoresces when examined under a fluorescent microscope. What can be concluded from this test?
The rabies virus is present in the patient's brain.
The Food and Drug Administration (FDA) is one of the oldest consumer protection agencies. Started in 1848, today the FDA protects consumers in a variety of ways, ranging from regulating food and drugs to helping speed product innovation. The regulation of drugs, including vaccines, is probably one of the best known tasks of the FDA. The regulation of vaccine products is specifically handled by the Center for Biologics Education and Research (CBER). The CBER ensures the safety, purity, and potency of vaccine preparations. All vaccines must undergo an extensive review of both laboratory and clinical data. As you work through the questions in this activity, imagine that you are a microbiologist working in the CBER, focusing on review of a potential new vaccine. One of the major contributors to our understanding of vaccination was Edward Jenner. What is Jenner's contribution to the development of vaccinations?
He demonstrated that inoculating people with crusts from cowpox lesions protected them from smallpox infection
The abbreviation (MBC/MIC/MID) stands for the smallest amount of a drug that will inhibit the growth and reproduction of a pathogen.
MIC (minimum inhibitory concentration)
Bacteria that are resistant to sulfonamide have enzymes that have a greater affinity for what?
PABA
What role does pressure play in an autoclave?
Pressure is applied to boiling water to prevent heat from escaping as steam.
If a particular bacterial species is resistant to beta-lactam antibiotics, which of the following might you expect to find inside the bacterial cells?
R plasmids
How might efflux pumps increase antibiotic resistance in bacteria?
Resistant bacteria can have more efflux pumps, and can have less specific efflux pumps.
What would be the best way to avoid resistance using an antimicrobial drug?
Use a single drug that acts on multiple targets
Which of the following is not true about vaccinations?
Vaccines are now available for all infectious diseases, although they are not available to all people.
Some bacteria are resistant to erythromycin as a result of mutation of their ribosomal RNA. What type of resistance does this represent?
alteration of the target of the drug
Which category of antimicrobial drug works by changing the shape of a ribosome?
aminoglycosides
Which of the following is a possible side effect of immunization with an inactivated vaccine?
both allergic reaction and toxicity
Almost a century after Edward Jenner introduced successful vaccination, Louis Pasteur developed vaccine(s) against
both anthrax and rabies
Which of the following can result when antibiotic therapy disrupts the normal microbiota?
both pseudomembranous colitis and thrush
Infection of the ________ would be the hardest to treat with antimicrobial drugs.
brain
An autoclave is able to achieve temperatures higher than that of boiling water
by increasing the pressure
Which antimicrobial drugs affect the structure of the ribosome itself?
aminoglycosides, antisense nucleic acids, and oxazolidinones
Vaccine manufacturers add alum, which is a common name for a variety of aluminum salts, to some vaccines. Alum enhances the ability of the vaccine to activate an adaptive immune response. Alum in such a vaccine acts as
an adjuvant
Killed vaccines work by stimulating
an antibody response
A color change will occur during an ELISA when a substrate reacts with _____.
an enzyme
Measles vaccine is to a modified live vaccine what rabies vaccine is to ______________ vaccine.
an inactivated (killed), whole agent
Oxidizing agents such as chlorine or hydrogen peroxide are particularly effective against __________ organisms
anaerobic
Individuals with egg allergies cannot receive flu vaccines because of the risk of which of the following?
anaphylactic shock
One area of focus during review of the application is complications associated with delivery of the new vaccine. Which of the following are possible complications of vaccination?
anaphylactic shock residual virulence fever and/ or seizures
The attenuated oral poliovirus vaccine (OVP) is no longer administered in the U.S.A. because it
can be spread to contacts and can occasionally cause poliomyelitis.
Which of the following is NOT associated with microbial mechanisms of resistance?
denaturation of proteins
Where are you likely to find an autoclave?
dentist office
Serious cases of diphtheria are treated with
antibiotics and diphtheria antitoxin
The "immuno" part of ELISA refers to a critical component of the assay, the _____.
antibodies
When conducting a sandwich ELISA, _____ are used to coat the wells of the plate.
antibodies
Which would be more likely to cause vaccine failure?
antigenic shift
A sandwich ELISA, unlike a regular ELISA, actually detects the presence of _____ in a patient's serum.
antigens
Which category of drug is complementary to mRNA of the pathogen?
antisense nucleic acids
Seasonal flu nasal spray vaccines contain weakened viruses. Such vaccines are called __________ vaccines.
attenuated
Which of the following types of vaccines should not be given to pregnant women or immunocompromised individuals?
attenuated
Reducing the use of antibiotics will
remove the selective pressure, but have little effect on the persistence of antibiotic resistance.
Dr. Paul Ehrlich observed that the differential stain developed by Dr. Gram suggested bacteria could be killed differentially by chemicals (Chapter 1). He called these potential antibacterial agents "magic bullets". Which among the following cell features of bacteria are potential targets for Dr. Ehrlich's "magic bullets" due to significant difference or absence from humans? Choose all that apply.
ribosome cell wall
Semisynthetic drugs developed to combat resistance are often called (analog/second generation/synergist) drugs.
second generation
The property of a chemical agent to be more inhibitory for a pathogen than for the pathogen's host is referred to as
selective toxicity
Which of the following is the most appropriate pairing of microbe and biosafety level?
methicillin-resistant Staphylococcus aureus (MRSA), BSL-2
Ben's infection is treated with imipenem. A drug such as imipenem is chemically modified from penicillin. What are non-natural drugs developed from natural drugs called?
semisynthetics
When performing a regular ELISA, the enzyme-linked antibodies are washed away unless they attach to _____.
serum antibodies
Which of the following activities can be shown to increase antimicrobial drug resistance among microbial populations?
taking antibacterial drugs for viral infections
New vaccine strategies resulting from progress in biochemistry, genomics and biotechnology include the production of
synthetic peptide-based vaccines.DNA vaccines.virosomes.non-Alum-based adjuvants.
A scientist wishes to produce a recombinant DNA vaccine. Which of the following would be most useful for this task?
plasmids
Which of the following viruses has not been used as the basis for a live recombinant vaccine?
poliovirus
Chloramphenicol blocks the action of the large (50S) subunit. This essentially _____.
prevents the formation of peptide bonds
Boiling for ten minutes does not kill ___
endospores
What is the function of tRNA during the process of translation?
tRNA brings amino acids to a growing chain of amino acids in ribosomes.
The therapeutic window of an antimicrobial is the
range of concentrations at which the antimicrobial is both effective and non-toxic.
A scientist develops a new medication that is a protein compound and that must be administered by injection. Which of the following would be the most effective and safest means of preparing a sterile solution of the new medication?
filtration
Which of the following substances is commonly used to inactivate microbes?
formaldehyde
Attenuated virus vaccines can be produced by which of the following processes?
growth in tissue culture cells for many generations
Desiccation, a time-honored method of preserving food, is effective because the
water content is too low to support metabolic function
Some microbes are halophiles and can withstand a high concentration of salt in their environment. What happens to nonhalophiles under such a condition?
water leaves the cell
Activation of which type of lymphocytes results in the production of memory cells?
Immature B and cytotoxic T cells
Determine which of the following statements is true or false and then select the correct answer sequence 1. The term antimicrobial agent includes antibiotics, fungicidal and anti-parasitic agents. 2.Bacteriostatic agents inhibit bacterial growth, but do not specifically kill the organisms against which they are directed. 3. Agents that inhibit bacterial cell wall synthesis can be bactericidal. 4. Antiseptics are sufficiently nontoxic that they can be applied to skin.
1. True 2. True 3. True 4. True
A particular sterilization process takes 60 minutes to kill all the microorganisms in a sample with 10^6 microbes. How long does it take to eliminate 90% if the organisms using this process.
10 minutes
It has been determined that the temperature in an autoclave should reach __________ for sterilization.
121 deg C
An increase or non-increase of the post-vaccination rate of adverse events may give a clue on whether the event is actually caused by the vaccine. In addition, observing the rate of an adverse event in the vaccinated population and comparing it with the rate of that event among the unvaccinated population can help distinguish genuine vaccine reactions. Imagine that rumors begin to circulate about a vaccine when cases of convulsions following immunization occur amongst vaccinated infants. The background rate of convulsions in this population is 1:1,000 infants. The observed rate of convlusions in vaccinated infants is 1.2:1,000. What is the vaccine attributable rate derived from these figures?
2 additional cases of convulsions in every 10,000 vaccinations, compared with the background rate
Vaccines are normally scheduled in infancy and early childhood, when illnesses are common and congenital or early neurological conditions become apparent. During a mass vaccination campaign, coincidental events are inevitable when vaccinating children in these age groups. Immediate investigation of a severe adverse event attributed to a vaccine, but not causally related to it is critical in order to respond to a community's concern about vaccine safety and to maintain public confidence in immunization. Calculating the expected rate of an adverse event is important. Based on the data in the table, how many infant deaths are expected to occur coincidentally (i.e. not linked to the DPT vaccine) in China the day after the vaccine is administered?
2,421
Prokaryotes contain _____ ribosomes.
70S
The cytosol of bacteria contain ____________ which has/have components different from those of the functionally equivalent structure of eukaryotes.
70S ribosome
For each of the following antibiotic response plots, match the appropriate description
A
Which of the following depicts the response of a bacterial population to treatment with a bacteriostatic agent?
A
The vaccine described in the application you're reviewing is a modified live vaccine. Which of the following describes possible recombinant technologies that could have been used to generate the vaccine?
A recombinant viral particle was created to express a particular antigen. One of the viral virulence genes was deleted, creating a viral strain with decreased virulence.
What is most likely to happen if an antimicrobial agent affects both pathogens AND normal microbiota?
A secondary infection can develop.
Which of the following would contribute to original antigenic sin in a vaccine?
A vaccine targeting one specific protein from a pathogen.
The majority of licensed vaccines today consist of all but which of the following antigenic preparations?
Acellular antigens derived from bacteria or viruses
Which of the following is the easiest way for bacteria to develop antibiotic resistance?
Acquire a conjugative plasmid harboring an antibiotic resistance gene.
Both active and passive immunotherapy are based on antibody-mediated responses. Which of the following statements about active immunotherapy is true?
Active immunotherapy provides long-term protection due to the generation of memory cells.
Which of the following does NOT describe the ideal antimicrobial agent?
Active in the body for an extended period of time
Which of the following is currently being applied or developed as alternative treatment strategies in cases of antimicrobial resistance?
All: Probiotics Combination therapy Augmentation therapy Bacteriophage therapy
Which of the following statements is incorrect?
Aluminum salts primarily serve to slow the escape of the antigen from the site of injection, which provides longer exposure of the antigen to the immune system for increased vaccine effectiveness
Although vaccines used in nation immunization programs are considered safe and effective, vaccines are not risk-free and adverse events will occasionally occur following vaccination. Public trust in vaccine safety is key to the success of vaccination programs. An adverse event following immunization is any untoward medical occurrence after immunization, which does not necessarily have a causal relationship with the usage of the vaccine. Which of the following is a correct statement with regard to an adverse event following immunization?
An adverse event following immunization can be due to an adverse reaction due to (ABC)
What is the greatest risk of a flu shot?
An allergic response to egg proteins.
What is the primary benefit of vaccination?
An immune response will occur quicker upon future exposure to the pathogen.
If someone is injected with tetanus toxoid, what type of immunity results?
Artificial active immunity
Which type of vaccine could possibly cause a person to develop the disease?
Attenuated live vaccine
Which of the following drugs would make the best antimicrobial?
B
What is the most likely biosafety level of your introductory microbiology lab classroom?
BSL- 1
Which biosafety level requires that laboratory air be HEPA-filtered but is insufficient for the safe study of Ebola?
BSL- 3
Most antibiotics come from what source?
Bacteria
Why is autoclaving rather than boiling water used for sterilization?
Boiling water does not kill everything, including bacterial endospores and some protozoan cysts.
What is meant by selective toxicity?
Chemotherapeutic agents should act against the pathogen and not the host.
Membrane transport proteins are required for which mode(s) of antibiotic resistance?
Efflux pumps, beta-lactamases, and modification of porins all utilize membrane transport proteins.
Why do endospores form?
Endospores form as a defense strategy against inhospitable conditions.
Smallpox was declared eradicated in 1979. Which of the following best describes what this means and how it differs from elimination of the disease?
Eradication refers to the complete and permanent worldwide reduction to zero new cases of the disease through deliberate efforts. Elimination refers to the reduction to zero (or a very low defined target rate) of new cases in a defined geographical area.
During her research on the HPV vaccine, Kelly finds lots of information on the diseases, such as genital warts and cervical cancer, that can be caused by the human papillomavirus. The information she finds is quite scary, and she begins to realize why her mother is concerned. Image A represents genital warts caused by HPV. Kelly also learns that these visual lesions are typically caused by viral serotypes 6 and 11 and rarely cause cervical cancer. The serotypes that are most likely to cause cancer are 16 and 18, but they have a relatively low prevalence (prevalence refers to the fraction of the population that has a specific disease at a given time). This explains why women should have regular Pap smears. A Pap smear is a diagnostic tool in which the physician removes a sample of cervical cells and places them on a microscope slide. Lab technicians then view the sample for abnormalities that may indicate the presence of cancerous cells. For women who are at high risk for cervical cancer, the physician may also recommend sending a sample for testing with an HPV DNA probe. A positive diagnosis can be made based on the presence of viral DNA. Kelly learns that the diagnosis of HPV may rely on the presence of viral DNA. Other infectious agents can be diagnosed based on immunologic responses. Which of the following represents an immunologic-based diagnostic test?
Fluorescent-antibody techniques Agglutination reactions Precipitation reactions
Considering the cell structure of mycoplasmas and other bacteria that stain either Gram negative, Gram positive, or with acid-fast stains, which group should you expect relies most on the presence of peptidoglycan for strength?
G+ bacteria
Which of the following reasons would not be predicted to cause vaccine failure in pigs?
Giving the vaccine during morning feeding
Why are chemotherapeutic agents that work on the peptidoglycan cell wall of bacteria a good choice of drug?
Humans and other animal hosts lack peptidoglycan cell walls.
Why do containers of liquid placed in an autoclave need to remain at least slightly open?
If they remain closed, they may implode.
Which type of antibody is produced first and in greater amounts upon subsequent exposures to an antigen (weeks, months, years, or decades after the initial exposure)?
IgG
An infectious disease researcher isolates the pathogen responsible for an emerging disease. The microbe is grown in the lab. A preparation of the laboratory grown microbe is treated with a lethal dose of ionizing radiation and then tested for its potential as a vaccine. What type of vaccine is this?
Inactivated whole
Many adjuvants can cause inflammatory reactions that make vaccines containing them problematic. Without an adjuvant, which of the following modifications would make an inactivated vaccine more effective?
Increase the dosage and number of doses of the vaccine.
What is the function of boosters?
Injections that are given periodically to maintain immunity.
Why is polymyxin only used on the skin?
It can also damage living human cell membranes, but the drug is safely used on the skin, where the outer layers of cells are dead.
Why is using an adjuvant in a vaccine preparation advantageous?
It enhances the immunogenicity of the antigen.
Which of the following is the one cardinal rule for a workable vaccine?
It must contain an antigen that will provide protection but not cause the disease.
Which of the following is not a quality of an effective vaccine?
It should require periodic boosters to maintain its effectiveness.
Consider a mesophilic bacterium. What would happen if this bacterium were exposed to a temperature much higher or lower than its optimal temperature?
It would stop growing and possibly be killed.
When a person has previously been vaccinated against a viral pathogen, which cells are activated if that same pathogen re-enters the host's cells months or years later?
Memory cytotoxic T cells
Of the microbes classified as aerotolerant anaerobes, facultative anaerobes, microaerophiles, obligate aerobes, and obligate anaerobes, which would be harmed by a high concentration of oxygen in their environment?
Microaerophiles and obligate anaerobes
What term best describes an organism that is resistant to three or more different antimicrobial agents?
Multiple-drug-resistant
In the most commonly performed version of an ELISA, two wells both exhibit the color change indicative of a positive result. However, the color in one well is much more intense than in the other well. What is the interpretation of this result?
One sample contains more antibody than the other.
The tRNA molecule holding a growing polypeptide chain is at the _____.
P site
Which of the following statements about pasteurization is NOT true?
Pasteurization is a method of sterilization that kills microbes present in food.
What effect does penicillin have on susceptible bacterial cells?
Penicillin disrupts cell wall synthesis
Why would an efflux pump for penicillin located on a bacterial cell membrane not be effective at providing resistance to the drug?
Penicillin disrupts the cell wall, which is located outside of the cell membrane
What is the difference between prokaryotic and eukaryotic ribosomes?
Prokaryotic ribosomes consist of a 50S large and a 30S small subunit, while eukaryotic ribosomes consist of a 60S large and a 40S small subunit.
Kelly is arguing with her mother about going to the doctor after school tomorrow. Kelly is only 14 and is embarrassed that her mother, Molly, has scheduled an appointment for her to visit a gynecologist. Molly tries to reassure her daughter that this visit is to discuss the human papillomavirus (HPV) vaccine. Molly recently saw a TV commercial recommending this vaccine for girls between the ages of 12 and 26. Given that Kelly is already 14, her mother does not want her to miss out on the opportunity to get vaccinated. Molly had taken an immunology course in college and is aware of the benefits of vaccinations. To help ease her daughter's mind, she prints out some information about the history of vaccines and how they help to stimulate the immune system. The earliest vaccinations were against smallpox. Which of the following statements about the history of smallpox vaccinations is FALSE?
Proteins from dairy cows were injected into people to protect them from smallpox.
The Hepatitis B vaccine is which type of vaccine?
Subunit vaccine
Some antimicrobial drugs can work in tandem with one another to produce an enhanced antimicrobial effect. What is this process called?
Synergism
Why is it necessary to give the HPV vaccine in multiple doses?
The HPV vaccine does not replicate in the host.
Which of the following statements is incorrect??
The TB-BCG vaccine is a typical example of a conjugate vaccine that provides better protection for infants compared to polysaccharide vaccines.
By what mechanism do bacteria develop resistance to tetracycline?
The bacteria prevent entry of tetracycline into the cells.
What is meant when a bacterium is said to become "resistant" to an antibiotic?
The bacterium is neither killed nor inhibited by the antibiotic.
Why do the beta-lactam drugs affect bacteria but NOT human cells?
The beta-lactam antibiotics act on bacterial cell walls; human cells do not have cell walls.
Typically, beta-lactam drugs affect the peptidoglycan layer on bacteria. Why would beta-lactam drugs typically be considered more active against Gram-positive bacteria and less so against Gram-negative bacteria?
The cell walls of Gram-positive bacteria have a thick peptidoglycan component.
Contaminated hospital equipment represents a difficult environment to control harmful microbial growth. Regarding influences that affect disinfection of hospital equipment, which of the following is an accurate statement?
The cell walls of many gram-negative bacteria are especially resistant to many chemicals that are used to destroy microbes
Which of the following reasons does not explain why developing resistance to vaccines less likely to occur than developing resistance to antimicrobial drugs?
The host immune response induced by a vaccine targets pathogens more rapidly than antimicrobial drugs.
Which part of an antibody is responsible for recognizing a specific antigen?
The variable regions of the light and heavy chains
Tetanus toxin mixed with antibodies against the toxin and then administered to mice will result in which of the following?
There will be no effect of tetanus toxin on the mice.
What is the hallmark of a conjugated vaccine?
These vaccines contain weakly antigenic elements plus a more potent antigenic protein.
How do scientists ensure that autoclaved materials were actually sterilized?
They may place a sterility indicator with a special dye to detect the growth of endospores.
Shiga toxins cause human cell damage and kill patients. If some scientists are making a vaccine using deactivated Shiga toxin, what category of vaccine would it be?
Toxoid vaccine
Which of the following BEST describes why it is difficult to develop antiviral drugs?
Viruses are hard to target because they often use the host cell's enzymes and ribosomes to metabolize and replicate.
Why is it difficult to find good chemotherapeutic agents against viruses?
Viruses depend on the host cell's machinery, so it is hard to find a viral target that would leave the host cell unaffected.
What does a vaccine contain?
Weakened or killed pathogen or parts of a pathogen
A negative result for an ELISA test would be the observance of _____ in the well.
a lack of color change
In which of the following situations would pooled antisera from human donors be a better choice for passive immunotherapy than would horse-derived antisera?
a patient receiving long-term immunotherapy for an immunodeficiency disease
A person who has been exposed to rabies receives both HRIP (human rabies immunoglobulin) injected near the bite site and the rabies vaccine. What does this strategy provide?
active immunization and passive immunotherapy
What is the most efficient and cost-effective way to control infectious diseases?
active immunization by vaccination
A person who has been exposed to rabies receives both HRIG (human rabies immunoglobulin) injected near the bite site and the rabies vaccine. What does this strategy represent?
active immunization combined with passive immunotherapy
Put the following microbes in order of their resistance to antimicrobial agents, from least to most resistant:a. prionsb. enveloped virusesc. mycobacteriad. Gram-negative bacteria
b, d, c, a
Vaccines contain different components to make them effective; however, each component in a vaccine adds a potential risk of an adverse reaction. Which of the following is a list of common bacterial vaccine components that could contribute to the risk of an adverse reaction?
bacterial cell walls, glutaraldehyde, latex
R-plasmids are most likely acquired via
bacterial conjuation
A (bacteriocidal/bacteriostatic/inhibitory) concentration of a drug is one at which microbes survive but are not able to grow and reproduce.
bacteriostatic
Detection of antibodies in serum is sufficient to indicate infection in diseases
caused by pathogens rarely found in a population
Antibiotic resistance is
clinically important because it results in increased morbidity and mortality
The microbial death rate is (constant/non-linear/variable) over time.
constant
The development of vaccines is considered the single most important application of immunology. What are the benefits associated with vaccinations?
control of viral disease herd immunity eradication of disease protection during travels
Some bacteria develop resistance to groups of drugs because the drugs are all structurally similar to each other; this is a phenomenon known as (cross/multiple/synergistic) resistance.
cross
Some bacteria are resistant to antimicrobials due to the activity of ________, which removes many of them.
eflux pumps
Which category of people are least likely to mount a good response to a vaccine?
elderly
NASA wants to prevent the possibility of contaminating other planets or items in space with microbes from Earth. Which of the following would best be used to sterilize spacecraft being sent to space?
ethylene oxide
Which of the following would be used to sterilize a mattress?
ethylene oxide
Drug-resistant populations of microbes arise when
exposure to drugs selectively kills sensitive cells, allowing overgrowth of resistant cells.
You are a graduate student working in an immunology lab. You run a sample of multiple proteins using gel electrophoresis. Then you transfer the proteins from the gel to a nitrocellulose membrane. Finally, you incubate the nitrocellulose membrane with an antibody solution to identify a particular protein in the sample. Which of the following tests did you perform?
immunoblot
If you wanted to evaluate a new disinfectant for effectiveness under the conditions of its intended use, the best evaluation technique would be the __________ test.
in-use
The influenza vaccine is an example of a(n)
inactivated killed vaccine.
An infectious disease researcher isolates the pathogen responsible for an emerging disease. The microbe is grown in the lab. A preparation of the laboratory-grown microbe is treated with a lethal dose of ionizing radiation and then tested for its potential as a vaccine. What type of vaccine is this?
inactivated whole
The ratio of a medication's dose that can be tolerated to its effective dose is the therapeutic (index/range/window) of the medication.
index
The DTaP vaccine is given four times in the first 18 months of life because __________.
it is a combination of a toxoid vaccine and subunit vaccine
The success rate of newly desgined vaccines is ________ ?
less than antimicrobial drugs
The microbial growth curve has four phases: lag, log, stationary, and death. If a chemical could prevent microbial cell division, in which phase of growth would it be most effective?
log phase
Which category of antimicrobial drug essentially acts to stall a ribosome as it reads mRNA?
microlides
Moist heat kills microbes faster than dry heat because
moist heat kills microbes by denaturing protein and nucleic acid structures and disrupting cell membranes, which takes less time to kill cells than removing water by dry heat and killing cell through oxidation reactions.
Vaccines fail _______ and take _________ to bring to market than antimicrobials.
more regularly / longer
Geogemma barossii is a hyperthermophilic archaeon that grows near hydrothermal vents in the ocean at temperatures as high as 121___ deg С. What effect would standard autoclaving have on this microbe?
nothing
Which antibiotic is overcome by beta-lactamases?
penicillin
The ____________ is a defining characteristic of bacteria which is not found in eukaryotes and is therefore a good choice for chemotherapeutic agents.
peptidoglycan cell wall
Which of the following mutations would not result in antibiotic resistance?
silent mutation
The pharmaceutical industry has been trying to develop antibiotics by rational drug design. This strategy involves
solving the crystal structures of target proteins and using computational modeling to design molecules that fit into the active site of this target.
Heating a broth culture of microorganisms to 140 deg C for three seconds would ___ the culture.
sterilize
A particular microbe gains resistance to gentamicin. You might also expect this microbe to exhibit resistance against __________.
streptomycin
Which of the following is a basic type of vaccine?
subunit vaccinelive attenuated vaccine nucleic acid vaccine
When a patient is treated with antibiotics, __________.
the drug will kill or inhibit the growth of all of the sensitive bacterial cells
Antimicrobial drugs are selectively toxic. This means _____.
the drugs are more toxic to the pathogens than to the patient
Development of new vaccines has slowed in recent decades. This is due to
the high cost of development.
Development of new vaccines has slowed in recent decades. This is due to
the high level of risk with immunization that cause adverse effects
Handwashing with regular soap is effective because __________.
the hydrophobic end of the soap molecule breaks up oily deposits and the hydrophilic end of the molecule attracts water. This combination makes soap a good degerming agent.
When microbial control methods are used, microbes are destroyed at a constant rate; there is no instantaneous death of all the microbes present. That microbial death rate is influenced by all of the following factors EXCEPT
the toxins and metabolites produced by the bacteria
It is inappropriate to prescribe antibacterial agents to treat colds or flu because
these diseases are caused by viruses
Why are endospores sometimes used in sterility indicators?
they are the hardest life form to kill
Which of the following would not be considered a source of perceived vaccination failure?
time of year of vaccination
What is the purpose of an autoclave?
to sterilize equipment and media
External infections can be treated by (intramuscular/surface/topical) administration, in which a drug is applied directly to the site of infection.
topical
The process of acquiring antibiotic resistance by means of bacteriophage activity is called
transduction
Which of the following is most susceptible to antimicrobial agents?
vegetative bacteria