Micro Exam III Practice Questions

Which of the following is the mostly likely characteristic of Campylobacter jejune?

X A: causes a severe watery diarrhea and can be acquired from eating under-cooked crabs

X B: commonly causes a serious systemic infection involving multiple organs and resides in the gallbladder of carriers

X C: acquired as a zoonotic infection, often from undercooked chicken, and causes a mild, self-limiting gastroenteritis

X D: moves within host cells by polymerizing actin

X E: always remains on the surface of host intestinal epithelial cells during an infection

acquired as a zoonotic infection, often from undercooked chicken, and causes a mild, self-limiting gastroenteritis

Cholera toxin has the effect of raising the level of what intracellular signalling molecule? __1__ FILL IN THE BLANK

cAMP

What is the "enterobacterial common antigen"?

X A: H-antigen

X B: core sugars within lipopolysaccharides (LPS)

X C: a capsule polysaccharide

X D: a type III secretion system protein

X E: heat-labile enterotoxin (LT)

core sugars within lipopolysaccharides (LPS)

What is the effect of shiga toxin within a host cell during an infection?

X A: inactivate 60S ribosomal subunit

X B: increase cellular protein translation

X C: shut off transcription of host mRNAs

X D: degrade the extracellular matrix in tissue

X E: increase cAMP levels

inactivate 60S ribosomal subunit

What is not a property associated with Salmonella enterica serovar typhi?

X A: invades M cells

X B: survive in macrophages

X C: presence in the oropharynx in asymptomatic carriers

X D: replicates in multiple organs, compromising their functions

X E: causes diarrhea

presence in the oropharynx in asymptomatic carriers

What is a property associated with Helicobacter pylori?

X A: resides only in the oropharynx

X B: VacA protein is a superoxide dismutase

X C: metabolizes urea to make the local environment more basic (increase pH)

X D: bacterium is not motile (no flagellum)

X E: most infected individuals are symptomatic with severe disease

metabolizes urea to make the local environment more basic (increase pH)

What non-invasive bacterium adheres to respiratory tract surfaces where it causes massive mucus production and a characterisitic cough that is severe enough to crack ribs and burst blood vessels?

X A: Bordetella pertussis

X B: Corynebacterium diphtheriae

X C: Francisella tularensis

X D: Yersinia pestis

X E: Bacillus anthracis

Bordetella pertussis

What is a property of Corynebacterium diphtheriae?

X A: infections often involve major bacteremia

X B: bacterium is a Gram-negative rod

X C: produces an ADP-ribosylase that targets host elongation factor 2

X D: effects of bacteria mainly caused by bacterial endotoxin

X E: infections cause whooping cough

produces an ADP-ribosylase that targets host elongation factor 2

The ability of Pseudomonas aeruginosa to produce a biofilm is dependent on

X A: spore formation

X B: alginate production

X C: capsule production

X D: bacterial motility

X E: shedding of lipopolysaccharide

alginate production

Botulism results in

X A: flaccid muscle paralysis due to blocking release of the neurotransmitter glycine

X B: spastic muscle paralysis due to blocking release of the neurotransmitter dopamine

X C: flaccid muscle paralysis due to blocking release of the neurotransmitter GABA

X D: spastic muscle paralysis due to blocking release of the neurotransmitter glycine

X E: flaccid muscle paralysis due to blocking release of the neurotransmitter acetylcholine

flaccid muscle paralysis due to blocking release of the neurotransmitter acetylcholine

What is associated with Clostridium difficile?

X A: tissue invasion

X B: gas gangrene

X C: flaccid paralysis

X D: spastic paralysis

X E: pseudomembranous colitis

pseudomembranous colitis

Which Clostridial species is the only one that invades tissue during an infection?

X A: Clostridium perfringens

X B: Clostridium difficile

X C: Clostridium botulinum

X D: Clostridium tetani

X E: no Clostridial species are invasive

Clostridium perfringens

FILL IN THE BLANK: What Gram-negative coccobacillus is transmitted zoonotically mainly from contact with wild animals such as birds, rabbits, or tick bites? The bacteria are able to grow in macrophages, resulting in systemic spread that can lead to ulceroglandular, oculoglandular, and pulmonary infections. A vaccine is available for high-risk individuals. __1__

Francisella tularensis

A vaccine against capsule b polysaccharides is effective for preventing systemic diseases caused by what gram negative cocco-bacilli that are often part of the normal flora of the oropharynx?

X A: Neisseria meningitidis

X B: Haemophilus influenzae

X C: Streptococcus pneumoniae

X D: Klebsiella pneumoniae

X E: Mycoplasma pneumoniae

Haemophilus influenzae

What bacterium normally lives inside amoeba in the environment and causes a severe pneumonia in elderly individuals? __1__ FILL IN THE BLANK

Legionella pneumophilia

What bacterium grows at tempertures from 1oC to 45oC, is resistant to salt and acid conditions, and is a food-borne pathogen that causes systemic disease in immune-compromised individuals? __1__ FILL IN THE BLANK

Listeria monocytogenes

Which of the following is true about tuberculosis?

X A: a clinical symptom of the disease is the lack of a Mantoux reaction

X B: a 3 month course of penicillin is a standard treatment for the disease

X C: untreated, the disease usually progresses rapidly over the course of 1 week, leading to death

X D: most individuals exposed to the bacterial agent do not develop disease

X E: secondary tuberculosis often manifests with a rash over much of the body's skin surface

most individuals exposed to the bacterial agent do not develop disease

The Mantoux reaction is the result of a diagnostic test for exposure to what bacterium? __1__ FILL IN THE BLANK

mycobacterium tuberculosis

Which of the following is true for leprosy?

X A: the bacterial agent cannot survive in macrophages

X B: Bacille Calmette-Guerin (BCG) vaccination is standard in parts of the world where leprosy is endemic

X C: a 2 week course of penicillin is standard treatment for the disease

X D: the bacterial agent is readily transmitted by aerosol

X E: A strong TH1-response by infected individuals results in a good prognosis for recovery

A strong TH1-response by infected individuals results in a good prognosis for recovery

Which organism often produces a characteristic erythema migrans rash in the early stage of infection?

X A: Chlamydia trachomatis

X B: Borrelia burgdorferi

X C: Nocardia spp.

X D: Bordetella pertussis

X E: Listeria monocytogenes

Borrelia burgdorferi

What bacterium lacks peptidoglycan and is the agent of the most sexually transmitted infections, characterized by mucopurulent discharges? __1__ FILL IN THE BLANK

Chlamydia trachomatis

What is true about Mycoplasma pneumoniae?

X A: gram positive

X B: facultative anaerobe

X C: causes severe, life-threatening lung infections

X D: immune protection fades after recovery from infection

X E: elderly individuals protected by recommended vaccine

immune protection fades after recovery from infection

Bacteria of which genus are transmitted to humans by a bite of a wood tick and cause vascular hemorrhages due to the lysis of endothelial cells by cytotoxic T lymphocytes?

X A: Rickettsia

X B: Helicobacter

X C: Clostridium

X D: Chlamydia

X E: Vibrio

Rickettsia

Bacteria of which genus is are obligate intracellular pathogens?

X A: Rickettsia

X B: Treponema

X C: Clostridium

X D: Shigella

X E: Salmonella

Rickettsia

What spirochete is sexually transmitted from human to human and has an early stage lesion called a chancre?

X A: Treponema pallidum

X B: Chlamydia trachomatis

X C: Neisseria gonorrhoeae

X D: Bordetella pertussis

X E: Borrelia burgdorferi

Treponema pallidum

Name a dental abnormality uniquely associated with congenital syphilis. __1__ FILL IN THE BLANK

mulberry molars

Which property of bacteria in a dental biofilm is associated with decreasing the risk of dental caries?

X A: upregulation of genes for polysaccharide synthesis

X B: multiple sugar transporters

X C: slow growth

X D: increased activity of proton pumps

X E: upregulation of ammonia production from arginine and urea

upregulation of ammonia production from arginine and urea

Which is a property of bacteria in a dental biofilm is associated with increasing the risk of dental caries?

X A: downregulation of genes for polysaccharide synthesis

X B: slow transport of sugars into cells, leaving higher concentrations in the oral cavity

X C: rapid growth

X D: increased activity of proton pumps

X E: upregulation of ammonia production from arginine and urea

increased activity of proton pumps

Dental caries correlates with

X A: increased saliva flow

X B: decreased consumption of sucrose

X C: gingival thickening that occurs with age

X D: high numbers of mutans Streptococci

X E: regular removal of dental plaque

high numbers of mutans Streptococci

What role does ammonia production from arginine and urea play for oral bacteria?

X A: creation of an acidic (pH) local environment

X B: ammonia is used as a main nitrogen source

X C: creation of a more basic (pH) local environment

X D: ammonia demineralizes tooth surfaces

X E: ammonia activates proton pumps in the bacterial membrane

creation of a more basic (pH) local environment

Aggregatibacter actinomycetemcomitans is associated with which oral disease?

X A: Ludwig's angina

X B: caries

X C: gingivitis

X D: aggressive periodontitis

X E: acute necrotizing ulceratize gingivitis

aggressive periodontitis

Spirochetes plus Fusobacterium nucleatum are strongly associated with which oral disease?

X A: Ludwig's angina

X B: caries

X C: gingivitis

X D: aggressive periodontitis

X E: acute necrotizing ulceratize gingivitis

acute necrotizing ulceratize gingivitis

What oral defense enzyme cleaves the bond between N-acetylglucosamine and N-acetylmuramic acid in bacterial peptidoglycan? __1__ FILL IN THE BLANK

lysozyme

What is an example of a role of a toll-like receptor in oral defense?

X A: cleave the bond between N-acetylglucosamine and N-acetylmuramic acid

X B: inhibit bacterial aggregation on epithelial surfaces

X C: form pores in bacterial membranes, disrupting cells

X D: bind to lipopolysaccharide and signal bacterial presence

X E: aggregate and clear oral bacteria via lectin-like interactions

bind to lipopolysaccharide and signal bacterial presence

Bacterial aggregates called "sulphur granules" are characteristic of what oral disease?

X A: Ludwig's angina

X B: a salivary gland infection

X C: periodontal abscess

X D: dental caries

X E: cervicofacial actinomycosis

cervicofacial actinomycosis

Which Streptococcal virulence factor is correlated with the progression of infective endocarditis?

X A: capsule

X B: proton pump

X C: glucosyltransferase

X D: platelet associated aggregation factor

X E: "sulphur granule" factor

platelet associated aggregation factor

Which disease has oral manifestations that include gummas, which can lead to perforations in the roof of the mouth?

X A: syphilis

X B: tetanus

X C: scarlet fever

X D: cholera

X E: gonorrhea

syphilis

What is a naked capsid virus composed of?

X A: only nucleocapsid

X B: only nucleocapsid + membrane

X C: only nucleic acid + glycoproteins

X D: only nucleic acid + enzymes

X E: only nucleocapsid + glycoproteins + membrane

only nucleocapsid

What is true about negative sense, single-stranded RNA viruses?

X A: require a viral RNA polymerase to be packaged into viral particles

X B: use host RNA polymerase as first enzyme during an infection

X C: use host DNA polymerase as first enzyme during an infection

X D: can directly translate viral RNA upon entry into a new host cell

X E: require reverse transcription as first enzyme during an infection

require a viral RNA polymerase to be packaged into viral particles

What is true about some small positive sense, single-stranded RNA viruses, like hepatitis A virus?

X A: require a viral RNA polymerase to be packaged into viral particles

X B: use host RNA polymerase as first enzyme during an infection

X C: use host DNA polymerase as first enzyme during an infection

X D: can directly translate viral RNA upon entry into a new host cell

X E: require reverse transcription as first enzyme during an infection

can directly translate viral RNA upon entry into a new host cell

What is an example of a host cell trait supplied by an viral genome integrated into the host cell genome?

X A: diphtheria toxin for Corynebacterium diphtheria

X B: tracheal cytotoxin for Corynebacterium diphtheria

X C: protein A for Staphylococcus aureus

X D: integrase for CD4+ T cells

X E: sialic acid for lung epithelial cells

diphtheria toxin for Corynebacterium diphtheria

What group of viruses is responsible for about 30% of cases of the "common cold" and has the largest genome of the RNA viruses (up to 30,000 nt)? __1__ FILL IN THE BLANK

coronavirus

What is the receptor for SARS-CoV-2, the agent of COVID-19?

X A: ICAM-1

X B: ACE2

X C: CD155

X D: CD46

X E: sialic acid

ACE2

What virus has an RNA genome that can be directly translated into protein, and transcribes more mRNAs, all of which are the size of the full viral genome, from a negative sense copy of the viral RNA genome?

X A: poliovirus

X B: adenovirus

X C: coronavirus

X D: influenza virus

X E: hepatitis B virus

poliovirus

What virus is transmitted by mosquitos from person-to-person and causes more severe disease in individuals that have partial immunity from a prior exposure to the virus?

X A: Dengue fever virus

X B: yellow fever virus

X C: eastern equine encephalitis virus

X D: cytomegalovirus

X E: coxsackievirus

dengue fever virus

What naked capsid viruses can cause an aseptic meningitis OR vesicles/ulcers on the tonsils and palate OR pleurodynia, depending on the subtype?

X A: mumps virus

X B: coxsackievirus

X C: herpes simplex virus type 1

X D: rabies virus

X E: HIV

coxsackievirus

Which virus is not spread by respiratory transmission?

X A: poliovirus

X B: varicella-zoster virus

X C: coronavirus

X D: rhinovirus

X E: measles virus

pollovirus

Which paramyxovirus has an incubation period of over 2 weeks and results in complications that include meningitis and orchitis?

X A: respiratory syncytial virus

X B: measles virus

X C: mumps virus

X D: rabies virus

X E: yellow fever virus

mumps virus

Antigenic drift in influenza viruses is caused by

X A: random packaging of double stranded DNA genome segments during a coinfection with two types of influenza viruses

X B: point mutations that occur during viral genome replication

X C: fragmentation of viral genomes by host enzymes

X D: random packaging of single stranded RNA genome segments during a coinfection with two types of influenza viruses

X E: recombination between single stranded RNA genomes during a coinfection with two types of influenza viruses

point mutations that occur during viral genome replication

What is true about respiratory syncytial virus?

X A: positive stranded RNA genome

X B: naked capsid virus

X C: typically spreads to multiple tissue sites in body

X D: can cause bronchiole obstruction

X E: mainly fecal-oral transmission

can cause bronchiole obstruction

Which of the following is true about Bacillus anthracis?

X A: produces an adenylate cyclase called edema factor

X B: produces an ADP ribosylase called lethal factor

X C: this is the only Bacillus species that does not form spores

X D: bacteria are Gram negative rods

X E: produces tracheal cytotoxin

produces an adenylate cyclase called edema factor

Clostridium botulinum produces an A-B exotoxin that blocks the release of which neurotransmitter from axon endings at neuromuscular junctions?

X A: acetylcholine

X B: glycine

X C: GABA

X D: dopamine

X E: serotonin

acetylcholine

Which Clostridial species is part of the normal human bacterial flora?

X A: Clostridium perfringens

X B: Clostridium difficile

X C: Clostridium botulinum

X D: Clostridium tetani

X E: no Clostridial species are part of the normal human bacterial flora

Clostridium difficile

Which of the following best describes tetanospasmin, a virulence factor for Clostridium tetani?

X A: A-B exotoxin that blocks acetylcholine release

X B: adenylate cyclase that activate motor neurons

X C: enzyme that degrades the neurotransmitter GABA

X D: A-B exotoxin that blocks release of the neurotransmitter glycine

X E: exotoxin that degrades extracellular matrix proteins

A-B exotoxin that blocks release of the neurotransmitter glycine

What virulence property does Haemophilus influenzae capsule b confer on these bacteria?

X A: allows the bacteria to cause systemic infections

X B: allows the bacteria to degrade host cell membrane

X C: allows the bacteria to be actively motile

X D: allows the bacteria to attach to host cell fibronectin

X E: allows the bacteria to degrade IgA

allows the bacteria to cause systemic infections

What bacterium lives inside amoeba in the environment and is typically transmitted by an aerosol route to humans through ventilation systems in buildings?

X A: Legionella pneumophila

X B: Listeria monocytogenes

X C: Bacillus anthracis

X D: Pseudomonas aeruginosa

X E: Streptococcus pneumoniae

Legionella pneumophila

What bacterium grows at tempertures from 1oC to 45oC, is resistant to salt and acid conditions, and is a food-borne pathogen that causes systemic disease in immune-compromised individuals?

X A: Legionella pneumophila

X B: Listeria monocytogenes

X C: Bacillus anthracis

X D: Pseudomonas aeruginosa

X E: Streptococcus pneumoniae

Listeria monocytogenes

This Gram-negative coccobacillus is transmitted zoonotically via fleas and eventually infects lymph nodes, producing a characteristic swellings called "bubos."

X A: Yersinia pestis

X B: Francisella tularensis

X C: Bacillus anthracis

X D: Brucella melitensis

X E: Borrelia recurrens

Yersinia pestis

A positive result with an acid-fast staining test of bacteria in a sputum smear is indicative of

X A: Mycobacterium tuberculosis

X B: rickettsias

X C: meningococci

X D: Treponema pallidum

X E: gonococci

Mycobacterium tuberculosis

Which of the following is true for cord factor of Mycobacterium tuberculosis?

X A: used for the Mantoux reaction diagnostic test for exposure to this bacterium

X B: is a glycolipid that adheres to cell surface mycolic acids

X C: contributes to smooth, flat appearance of bacterial colonies

X D: is the basis for the gram-positive staining of the bacteria

X E: is a cytotoxin that causes most of the host cell damage during infection

is a glycolipid that adheres to cell surface mycolic acids

Which of the following is true for leprosy?

X A: the bacterial agent cannot survive in macrophages

X B: Bacille Calmette-Guerin (BCG) vaccination is standard in parts of the world where leprosy is endemic

X C: a 2 week course of penicillin is standard treatment for the disease

X D: the bacterial agent is readily transmitted by aerosol

X E: A strong TH1-response by infected individuals results in a good prognosis for recovery

A strong TH1-response by infected individuals results in a good prognosis for recovery

What bacterium lacks peptidoglycan and is the agent of the most sexually transmitted infections, characterized by mucopurulent discharges?

X A: Neisseria gonorrheae

X B: Mycoplasma genitalium

X C: Chlamydia trachomatis

X D: Treponema pallidum

X E: Staphylococcus aureus

Chlamydia trachomatis

What symptoms are uniquely associated with tertiary syphilis?

X A: gummas

X B: rash

X C: chancre

X D: Hutchinson's incisors

X E: mulberry molars

gummas

What is the treatment for a child born with congenital syphilis to clear the infection?

X A: erythromycin

X B: penicillin

X C: no treatment is possible

X D: isoniazid

X E: tetracycine

penicillin

Hemolytic uremic syndrome is a complication of infection by which organism?

X A: Salmonella typhi

X B: Escherichia coli O157:H7

X C: Clostridium difficile

X D: Shigella dysenteriae

X E: Streptococcus pyogenes

Escherichia coli O157:H7

Which enteric bacterium can invade M cells in the gut, survive in macrophages, and eventually infect many different organs in the body?

X A: Salmonella enterica serovar typhi

X B: Shigella dysenteriae

X C: Vibrio cholera

X D: Enteropathogenic E. coli

X E: Campylobacter jejune

Salmonella enterica serovar typhi

Which bacterium produces the vast majority (70-90%) of urinary tract infections (bladder infections, for example)?

X A: Salmonella typhi

X B: Escherichia coli

X C: Klebsiella species

X D: Staphylococcus saprophyticus

X E: Campylobacter jejune

Escherichia coli

Which of the following is true about cholera?

X A: the causative bacterium is an obligate human pathogen

X B: supportive rehydration therapy is the main method used for treatment

X C: severe dehydration is not usually associated with this disease

X D: Vibrio cholera is normally transmitted by inhalation

X E: Vibrio cholera is a component of the normal human flora

supportive rehydration therapy is the main method used for treatment

What is a property associated with Helicobacter pylori?

X A: resides only in the oropharynx

X B: VacA protein is a superoxide dismutase

X C: metabolizes urea to make the local environment more basic (increase pH)

X D: bacterium is not motile (no flagellum)

X E: most infected individuals are symptomatic with severe disease

What is a property of the dissaccharide-tetrapeptide component of bacterial peptidoglycan that is the tracheal cytotoxin of Bordetella pertussis?

X A: it is a unique component of the Bordetella pertussis cell wall

X B: it is shed from bacterial cells instead of being absorbed and recycled

X C: it acts as an adenylate cyclase

X D: it is an A-B toxin that ADP ribosylates a G protein

X E: it is a fimbrial protein

it is shed from bacterial cells instead of being absorbed and recycled

In addition to multiple drug resistance mechanisms, what is another reason that lung infections with Pseudomonas aeruginosa are so resistant to antibiotic therapy?

X A: the bacterium's ability to form spores

X B: the bacterium's ability to form a biofilm

X C: the anaerobic environment the bacterium thrives in makes most antibiotics ineffective

X D: the fruity smelling compound the bacterium produces inactivates most antibiotics

X E: lipopolysaccharide

the bacterium's ability to form a biofilm

What is true of dental plaque?

X A: the first colonizing bacteria during plaque formation bind tooth enamel directly

X B: Prevotella oralis is an early colonizer

X C: epithelial cells produce glucans in response to the dental biofilm

X D: the pellicle is the coating that forms on the plaque surface after bacterial coaggregation

X E: sugar consumption causes increased levels of Streptococcus mutans in plaque

sugar consumption causes increased levels of Streptococcus mutans in plaque

What can lead to increased incidence of dental caries?

X A: increased saliva flow

X B: decreased consumption of sucrose

X C: gingival recession that occurs with age

X D: decreased presence of Streptococcus mutans

X E: removal of dental plaque

gingival recession that occurs with age

What is a property characteristic of cariogenic bacteria (versus noncariogenic bacteria)?

X A: decreased synthesis of extracellular polysaccharides

X B: reduced number of phosphoenol pyruvate phophotransferase system (PEP-PTS) transporters

X C: presence of acid stress response proteins

X D: decreased activity of proton pumps

X E: ammonia production from atmospheric nitrogen

presence of acid stress response proteins

Which genus of bacteria are typicaly associated with salivary gland infections?

X A: Fusobacterium

X B: Aggregatibacter

X C: Streptococcus

X D: Staphylococcus

X E: Actinomyces

Staphylococcus

What enzymes create an extracellular network of branched sugar polymers within dental plaque?

X A: glucosyltransferases

X B: phosphoenolpyruvate sugar:phosphotransferases

X C: dextranases

X D: arginine deiminases

X E: fermentation pathway enzymes

glucosyltransferases

How does lysozyme act as an antibacterial agent?

X A: lysozyme cleaves the bond between N-acetylglucosamine and N-acetylmuramic acid

X B: lysozyme inhibits the transpeptidation reaction that crosslinks peptidoglycan polymers

X C: lysozyme binds iron, making it unavailable for bacteria to use

X D: lysozyme inhibits bacterial and host cysteine proteases

X E: lysozyme aggregates and clears oral bacteria via lectin-like interactions

lysozyme cleaves the bond between N-acetylglucosamine and N-acetylmuramic acid

Which of the following is characteristic of Ludwig's angina?

X A: Staphylococcus aureus is the predominant organism

X B: facultative anaerobes are the predominant organisms

X C: infection is usually by a single bacterial species

X D: infection is polymicrobial (multiple species)

X E: is always characterized by "sulphur granules"

infection is polymicrobial (multiple species)

What is an enveloped virus composed of?

X A: nucleocapsid

X B: nucleocapsid plus protein shell

X C: nucleic acid plus glycoproteins

X D: nucleic acid plus enzymes

X E: nucleocapsid plus membrane plus glycoproteins

nucleocapsid plus membrane plus glycoproteins

Which class of virus always brings its own RNA polymerase into a cell during infection?

X A: double stranded DNA viruses

X B: positive-sense, single stranded RNA viruses

X C: negative-sense, single stranded RNA viruses

X D: single-stranded DNA viruses

X E: retroviruses

negative-sense, single stranded RNA viruses

What is an example of a host cell trait supplied by an viral genome integrated into the host cell genome?

X A: botulinum toxin for Clostridium botulinum

X B: tracheal cytotoxin for Corynebacterium diphtheria

X C: protein A for Staphylococcus aureus

X D: integrase for CD4+ T cells

X E: sialic acid for lung epithelial cells

botulinum toxin for Clostridium botulinum

What is a possible role for the gut bacteriophage community, as presented in lecture?

X A: bacteriophage replication may promote biolfilm formation by their host bacteria

X B: bacteriophage particles may activate T-cells

X C: bacteriophage may integrate into the genomes of gut epithelial cells and promote tumor formation

X D: bacteriophage may limit bacteria in the gut, killing off cells when they reach a high concentration

X E: bacteriophage are essentail components of bacterial CRISPR defense mechanisms

bacteriophage may limit bacteria in the gut, killing off cells when they reach a high concentration

Members of what enveloped, plus stranded RNA virus family can cause an acute respiratory syndrome that is an atypical pneumonia, but more often cause milder disease, generically referred to as the "common cold?"

X A: rhinovirus

X B: adenovirus

X C: coronavirus

X D: influenza virus

X E: coxsackievirus

coronavirus

What virus is responsible for about 50% of cases of the "common cold," has an RNA genome that can be directly translated into protein, and transcribes more mRNAs that are the size of the full viral genome from a negative sense copy of the viral RNA genome?

X A: rhinovirus

X B: adenovirus

X C: coronavirus

X D: influenza virus

X E: coxsackievirus

rhinovirus

What flavivirus is transmitted by mosquitos from person-to-person and from monkeys-to-humans and causes jaundice in severe cases?

X A: Dengue fever virus

X B: yellow fever virus

X C: eastern equine encephalitis virus

X D: cytomegalovirus

X E: coxsackievirus

yellow fever virus

What is true about Zika virus?

X A: It is a picornavirus

X B: It is transmitted by Ixodes ticks

X C: It is an enveloped, negative stranded RNA virus

X D: humans hosts cannot produce enough virus for transmission to others

X E: It causes congenital infections

It causes congenital infections

What naked capsid viruses can cause an aseptic meningitis OR vesicles/ulcers on the tonsils and palate OR pleurodynia,

depending on the subtype?

X A: mumps virus

X B: coxsackievirus

X C: herpes simplex virus type 1

X D: rabies virus

X E: HIV

X B: coxsackievirus

Which influenza virus protein mediates adsorption of the virus onto a host epithelial cell surface?

X A: neuraminidase

X B: F protein

X C: hemagglutinin

X D: protease

X E: E1a

hemagglutinin

Reassortment of genetic information among influenza viruses is possible because of

X A: random packaging of double stranded DNA genome segments during a coinfection with two types of influenza viruses

X B: high mutation rates during viral genome replication

X C: fragmentation of viral genomes by host enzymes

X D: random packaging of single stranded RNA genome segments during a coinfection with two types of influenza viruses

X E: recombination between single stranded RNA genomes during a coinfection with two types of influenza viruses

random packaging of single stranded RNA genome segments during a coinfection with two types of influenza viruses

What paramyxovirus initially infects cells of the respiratory tract but characteristically replicates in the parotid gland after viremia?

X A: poliovirus

X B: coronavirus

X C: HIV

X D: mumps virus

X E: hepatitis A virus

mumps virus

What virus is characterized by "negri bodies" in brain tissue?

X A: respiratory syncytial virus

X B: measles virus

X C: herpes simplex virus type I

X D: Epstein-Barr virus

X E: rabies virus

rabies virus

What paramyxovirus is limited to replication in the region of initial contact and does not demonstrate significant spread to other sites by viremia?

X A: respiratory syncytial virus

X B: measles virus

X C: mumps virus

X D: rhinovirus

X E: coronavirus

respiratory syncytial virus

What is NOT a property associate with the following 3 speicies of bacteria in the oral cavity: Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia?

X A: they are frequently isolated together

X B: they comprise the "Red complex"

X C: they are associated with healthy sites in the mouth

X D: one of them produces gingipains (cycstein-proteases)

they are associated with healthy sites in the mouth

Which enteric bacterium is acquired as a zoonotic infection, often from undercooked chicken, and causes a mild, self-limiting gastroenteritis?

X A: Salmonella enterica serovar typhi

X B: Shigella dysenteriae

X C: Vibrio cholera

X D: Enteropathogenic E. coli

X E: Campylobacter jejune

Campylobacter jejune

What pathogen resides in the stomach and induces the host to secrete urea through the mucosal epithelium?

X A: Helicobacter pylori

X B: Shigella dysenteriae

X C: Enterohemorrhagic E. coli

X D: Bacteroides fragilis

X E: Campylobacter jejune

Helicobacter pylori

Which of the following virulence factors is the dissaccharide-tetrapeptide component of bacterial peptidoglycan?

X A: shiga toxin of Shigella

X B: tracheal cytotoxin of Bordetella pertussis

X C: cholera toxin

X D: endotoxin

X E: heat labile enterotoxin (LT) of enterotoxigenic E. coli

tracheal cytotoxin of Bordetella pertussis

These gram positive rods establish themselves in the throat and kill cells by expressing a toxin that ADP-ribosylates elongation factor 2, causing inhibition of cellular translation.

X A: Bacillus anthracis

X B: Bordetella pertussis

X C: Corynebacterium diphtheriae

X D: Helicobacter pylori

X E: Pseudomonas aeruginosa

Corynebacterium diphtheriae

Which of the following describes Pseudomonas aeruginosa?

X A: agent of whooping cough

X B: ubiquitous Gram-positive rod

X C: complex nutritional requirements (need blood agar for lab growth)

X D: can grow at temperatures up to 43oC

X E: obligate intracellular pathogen

can grow at temperatures up to 43oC

Blockage of acetylcholine release from host cells is caused by a virulence factor of which bacterium?

X A: Yersinia pestis

X B: Mycobacterium leprae

X C: Clostridium perfringens

X D: Clostridium botulinum

X E: Clostridium tetani

Clostridium botulinum

What spore forming bacterium produces an A-B exotoxin that blocks GABA (gamma-aminobutyric acid) release from axon endings of interneurons that control motor neurons within muscles?

X A: Bacillus anthracis

X B: Clostridium tetani

X C: Clostridium perfringens

X D: Clostridium botulinum

X E: Clostridium difficile

Clostridium tetani