2023

Question 1

what viral agent of gastroenteritis has a single-stranded RNA genome and undergoes two pahses of translation like coronaviruses

Answer 1

norovirus

Question 2

what is a role of the HIV gp120 protein

Answer 2

binding to CD4 on host cell surfaces

Question 3

HIV mutates rapidly during an infection due to errors by which enzyme

Answer 3

viral reverse transcriptase

Question 4

what is the role of the HIV gp41 protein

Answer 4

fusion of viral and cellular membranes during viral entry

Question 5

in a study that I described in class, blood samples were taken monthly over a 39 month period from patients infected with HIV to follow the virus replicating in the patients’ systems and the patients’ antibody response. The patients became infected with HIV in month 0. What is a valid conclusion from the study?

Answer 5

month 12 plasma has anti-HIV antibodies that react strongly to month 0 virus but not month 12 virus

Question 6

how could the adenovirus E1b protein play a role in carcinogenesis

Answer 6

binds p53 and prevents activation in response to DNA damage

Question 7

which of the following is diagnostic for infection with human papilloma virus

Answer 7

koilocytic cells

Question 8

what is the cause of respiratory papillomatosis

Answer 8

warts of the oropharnyx caused by human papillomavirus infection

Question 9

what is not a defining property of herpesviridae family members

Answer 9

bring an RNA dependent RNA polymerase into a newly infected cell

Question 10

which virus is spread by respiratory transmission

Answer 10

varicella-zoster virus

Question 11

infection by which Human Herpes Viruses causes the following oral manifestations: painful sore throat at onset of infection, rash at the junction of hard and soft palates, and white pseudomembrane on the tonsils?

Answer 11

EBV only

Question 12

infection with which herpesvirus is commonly diagnosed by detection of heterophile antibody

Answer 12

EBV

Question 13

during hepatitis B virus infection, infectious viral particles are released from cells. what is a property of these particles

Answer 13

42nm diameter particles containing HBs antigen

Question 14

an individual who had a prior acute infection with HBV that completely resolved would display which of the follow serological properties

Answer 14

presence of anti-HBs antibodies combined with lack of detectable HBs and HBe antigens

Question 15

what virus does not create “giant cells” during the cource of an infection

Answer 15

hepatitis A virus

Question 16

what virus does not invade neurons

Answer 16

respiratory syncytial virus

Question 17

which drug blocks release of influenza A virus from an infected cell

Answer 17

tamiflu

Question 18

how does remdesivir, a drug for treating covid-19 act as an antiviral

Answer 18

is a nucleoside analog that inhibits viral RNA-dependent RNA

Question 19

how does paxlovid, a drug for treating covid-19 act as an antiviral

Answer 19

is an inhibitor of viral protease

Question 20

how does amantidine block infection by influenza A virus

Answer 20

inhibits viral disassembly in endosomes

Question 21

passive immunization is used for all of the following except

Answer 21

to elicit production of secretory antibodies

Question 22

which vaccine protects solely or principally by induction of serum antibodies

Answer 22

tetanus vaccine

Question 23

what strategy has been used to create a successful vaccine against haemophilus influenzae type b (Hib)

Answer 23

creating a vaccine from Hib capsular polysaccharide linked to a diphtheria toxoid molecule as the antigens

Question 24

how does the monoclonal antibody drug, first apporved in november 2020 for treating COVID-19 (with a new version approved more recently) act as an antiviral

Answer 24

binds spike (S) protein of SARS-CoB-2, blocking virions from interacting with ACE2 receptor

Question 25

which of the following is not true about Creuzfeldt-jakob disease (CJD)?

Answer 25

CJD is highly contagious

Question 26

what disease is caused by the conversion of a normal human protein to a form that aggregates as amyloid fibrils

Answer 26

fatal familial insomnia

Question 27

this fungus produces a thick capsule which is observed under the microscope with india ink staining

Answer 27

cryptococcus neoformans

Question 28

how does the anti-fungal fluconazole work

Answer 28

inhibiting cytochrome P450-dependent 14-alpha-lanosterol demethylation

Question 29

which fungal staining method dissolves host tissue but leaves fungal cells intact

Answer 29

potassium hydroxide treatment

Question 30

which characterisitic is not associated with fungi

Answer 30

cell walls contain N-acetyl-muramic acid polymers

Question 31

for fungi, to what does the term dimorphism refer

Answer 31

capability to grow as a yeast or mold

Question 32

which form of oral candidiasis involves superficial fungal growth with easily removeable plaques of fungi

Answer 32

acute pesudomembranous

Question 33

infection by which organism is not associated with the formation of granulomas in the lung

Answer 33

sporothrix schenkii

Question 34

which of the following is associated with coccidioides immitis

Answer 34

chronic meningitis

Question 35

what is meant by a definitive host when referring to a parasitic organism

Answer 35

the host in which the parasite’s sexual reproduction phase occurs

Question 36

what is a property assoicated with plasmodium falciparum

Answer 36

invades and lyses red blood cells

Question 37

the anaerobic metabolism of some protozoal pathogens makes them susceptible to which drug

Answer 37

metronidazole

Question 38

which genus contains the most commonly sexually transmitted protozoan disease agent

Answer 38

trichomonas

Question 39

salmonella-shigella agar (SS) is an example of which type of culture medium used for diagnosis of a bacterial infection

Answer 39

selective medium

Question 40

the “specificity” of a diagnositic-test measures the percentage of

Answer 40

true negative test results among the total of the true negative plus false positives

Question 41

what is the order of components for an ELISA test for microbial antigen detection in a patient blood serum sample? order reads right to left in answer choices. Step K= enzyme substrate added Step M= patient serum added Step X= enzyme conjugated antibody specific to antigen added

Answer 41

laboratory produced antibody specific for antigen bound to well surface; Step M; Step X; Step K

Question 42

what is the basis for a positive test result in a latex agglutination test for a pathogen?

Answer 42

presence of pathogen antigens in a sample cause agglutination of latex beads

Question 43

what is the morbidity rate for a disease

Answer 43

number of new cases in a specific time period per unit of population

Question 44

what does the term R0 mean with respect to the epidemiology of an infectious disease

Answer 44

the number of secondary cases that one cause of the disease would produce in a completely susceptible population

Question 45

in airborne disease transmission, what is a property of droplet nucle

Answer 45

particles of 4 micrometers or less in diameter

Question 46

what is true about a propagated epidemic

Answer 46

the number of cases begins to fall once the umber of susceptible individuals falls below the threshold density

Question 47

“universal precautions” means that

Answer 47

all patients are treated as though they are a source of infectious pathogens

Question 48

what is the spaulding classifcation category of a dental implant

Answer 48

critical

Question 49

what compounds are cationic detergents, making them effective wetting agents and emulsifiers that also kill most bacteria but are safe and easy to use even in households

Answer 49

quaternary ammonium compounds

Question 50

hexachlorophene is a member of what class of chemical agents used for microbrial control

Answer 50

phenolics