Microbiology Final
Sunny Acres Nursing Home has a total population of 100 residents. In the month of April, they recorded a total of 10 cases of Legionnaire's disease, with 1 new infection occurring that month. Based on this information, which number corresponds to the incidence of Legionnaire's disease in April at Sunny Acres? A. 1% B. 10% C. 100 D. 9% E. More information is needed to calculate incidence
A. 1%
An AIDS patient is diagnosed with meningoencephalitis. Which organism is most likely responsible for this condition? A. Cryptococcus neoformans B. Escherichia coli C. Naegleria fowleri D. Haemophilus ducreyi E. Histoplasma capsulatum
A. Cryptococcus neoformans
Erythema migrans is a hallmark symptom of: A. Lyme disease B. rabies C. hemolytic uremic syndrome D. meningococcal meningitis E. tapeworm infection
A. Lyme disease
A key goal of the immune system is to distinguish self from non-self. A. True B. False
A. True
A pathogen with a LD50 of 500 would be considered more virulent than a pathogen with a LD50 of 1000. A. True B. False
A. True
A superantigen triggers the production of a cytokine storm. A. True B. False
A. True
Antibiotics are capable of inhibiting or killing bacteria that are pathogenic. A. True B. False
A. True
In the preparation of toxoids, the antigenicity of the toxin remains while the toxic activity is eliminated. A. True B. False
A. True
Ingestion of Clostridium botulinum by an infant will result in botulism. A. True B. False
A. True
Innate immunity is nonspecific and adaptive immunity is specific. A. True B. False
A. True
Which of the following is an example of a zoonotic infection? A. an individual acquires a rabies virus infection after being bitten by a rabid raccoon B. an individual acquires infectious mononucleosis ("mono") after drinking from the same water glass as her infected friend C. an individual acquires cholera after drinking contaminated water D. all of the above
A. an individual acquires a rabies virus infection after being bitten by a rabid raccoon
You discover a new chemical and want to test its effect on the bacterium MRSA. After adding the chemical to the bacterial culture you find that its growth is inhibited until you remove the chemical and the cells start growing again. Which term best describes this chemical? A. bacteriostatic B. bactericidal C. fungistatic D. spirochete E. germicidal
A. bacteriostatic
Which of the following viral structures is most antigenic? A. capsid B. peptidoglycan C. envelope D. genome
A. capsid
Heather, an eight-year-old female, has scabs and pus-filled vesicles on her face, torso and throat. Three weeks earlier she had visited her grandmother, who had shingles. What infection does Heather have? A. chickenpox B. rubella C. measles D. erythema infectiosum E. cellulitis
A. chickenpox
What do Streptococcus pneumoniae, Treponema pallidum and Salmonella enterica serovar Typhi all have in common? A. humans are the only known reservoir for these organisms B. they are all transmitted through infectious aerosols C. they are all viruses D. most individuals are asymptomatic when infected with each organism E. infections with these pathogens can be prevented through vaccination
A. humans are the only known reservoir for these organisms
A 10 year old boy named Akal arrived at the local clinic complaining of profuse diarrhea and lack of energy. In addition, he showed visible signs of dehydration. The medical staff collected a stool specimen and performed a gram stain. Using a microscope, the medical technologist viewed the sample and observed cylindrical, gram-negative cells with the following dimension: 3 micrometers in length and 1 micrometer in width. Which of the following statements is/are true regarding this organism?
A. its cell envelope contains a polysaccharide B. it would best be described as a bacillus
All of the following are examples of exotoxins except: A. lipopolysaccharide B. cytotoxins C. enterotoxins D. neurotoxins
A. lipopolysaccharide
Which of the following anatomical sites is not colonized by normal microbiota? A. liver B. vagina C. intestines D. skin E. all of the above have normal microbiota
A. liver
Inflammation of the tissues that cover the brain and spinal cord is called ____. Symptoms of this disease include fever, headache, nausea, vomiting and a stiff neck. A. meningitis B. myocarditis C. conjunctivitis D. lymphadenitis E. none of the above
A. meningitis
Resident macrophages in the tissues digest a foreign microbe and release chemokines, which promote extravasation of which type of white blood cell to arrive at the site of infection? A. neutrophils B. dendritic cells C. natural killer cells D. B cells E. IgG
A. neutrophils
____ is generally the most serious disease associated with infection of the urinary tract. A. pyelonephritis B. urethritis C. salpingitis D. cystitis E. orchitis
A. pyelonephritis
Staphylococcus aureus is associated with all of the following except: A. rheumatic fever B. toxic shock syndrome C. scalded skin syndrome D. carbuncles E. food poisoning
A. rheumatic fever
Which of the following correctly lists the vector, reservoir and pathogen (in this order) of Lyme disease? A. ticks, rodents, Borrelia burgdorferi B. rodents, Borrelia burgdorferi, ticks C. Borrelia burgdorferi, ticks, rodents D. rodents, ticks, Borrelia burgdorferi E. ticks, Borrelia burgdorferi, rodents
A. ticks, rodents, Borrelia burgdorferi
Which of the following is an example of regulation caused by competitive inhibition?
An antibiotic binds to the active site of the first enzyme of a phospholipid synthesis pathways and prevents the natural substrate from binding, which shuts off the pathway.
Which of the following is an example of naturally acquired active immunity? A. A child is bitten by a bat and receives a high dose of antibodies prepared from donor serum B. An individual contracts COVID-19, experiences symptoms and recovers ~14 days later C. Maternal antibodies pass through the placenta into the bloodstream of the developing fetus D. An individual receives a vaccine against mumps virus and is protected from subsequent exposure to this pathogen
B. An individual contracts COVID-19, experiences symptoms and recovers ~14 days later
All of the following pathogens are capable of vertical transmission except: A. herpes simplex virus B. Babesia microti C. Listeria monocytogenes D. Neisseria gonorrhoeae E. Treponema pallidum
B. Babesia microti
An adaptive immune response to M protein produced by Corynebacterium diphtheriae is associated with the development of rheumatic fever. A. True B. False
B. False
An epitope is made up of many distinct antigens. A. True B. False
B. False
Dengue hemorrhagic fever occurs as a result of a secondary infection with the same serotype of the virus than the one that caused the primary infection. A. True B. False
B. False
Dermatophytes are group of protozoa that infect keratinized tissues. A. True B. False
B. False
Refrigeration causes death of endospores. A. True B. False
B. False
Which of the following is an example of an enanthem? A. folliculitis B. Koplik's spots C. reticular rash on the torso D. a wart on the finger E. a trophozoite
B. Koplik's spots
Which pathogen has a tropism for the parotid glands, causing severe swelling at this site? A. Naegleria fowleri B. Mumps virus C. Cryptococcus neoformans D. Norovirus E. Bordetella pertussis
B. Mumps virus
Bare lymphocyte syndrome is a genetic disease characterized by a total absence of MHC class II on the surface of certain types of cells. Individuals with this syndrome would: A. be more resistant to viral infections B. be unable to activate helper T cells C. be completely unable to respond to TLRs D. not have any complement factors E. lack a thymus
B. be unable to activate helper T cells
What do Hepatitis B virus and Hepatitis C virus have in common? A. both viruses are primarily transmitted through contaminated food or water B. both viruses are capable of causing cirrhosis and liver cancer C. both viruses cause an acute, self-limiting infection that typically resolves within 1 month D. both viruses require the presence of Hepatitis D virus in order to replicate E. both viruses primarily infect the spleen
B. both viruses are capable of causing cirrhosis and liver cancer
Disease caused by Clostridioides difficile or Gardnerella vaginalis usually results from a shift in the community structure of resident microbiota in a given environment, which is referred to as ____. A. symbiosis B. dysbiosis C. commensalism D. microbicide E. antagonism
B. dysbiosis
Which of the following statements about fever is false? A. fever is triggered by pyrogens B. fever promotes the growth of pathogens C. fever is an increase in body temperature, which is regulated by the hypothalamus D. fever encourages tissue repair
B. fever promotes the growth of pathogens
Because it is an essential component for every individual, supplements may be required if enough vitamin C is not found in the diet. Vitamin C is sensitive to heat. So that it can be safe for human consumption, how can a liquid solution of vitamin C be sterilized before being packaged into supplements? A. autoclave B. filtration C. pasteurization D. lyophilization E. treatment with a virucide
B. filtration
Which of the following modes of transmission would be considered indirect contact? A. mother to child B. fomites C. aerosolization D. person-to-person
B. fomites
Which of the following is an incorrect pairing? A. varicella zoster virus / chickenpox B. measles / pseudomembrane C. fifth disease / slapped cheek rash D. varicella zoster virus / shingles E. human papilloma virus / warts
B. measles / pseudomembrane
All of the following are normal defenses of the female reproductive tract except: A. mucociliary clearance B. neutral pH due to Lactobacillus C. secretory antibodies D. antimicrobial peptides
B. neutral pH due to Lactobacillus
Bacteria that reside in the nasopharynx can travel through the Eustachian tube to cause _____. A. gastritis B. otitis media C. sinusitis D. bacteremia E. meningitis
B. otitis media
Aminoglycosides are a class of bactericidal antibiotics that inhibit translation in bacteria. What is the mechanism of selective toxicity for this class of antibiotics? A. eukaryotes don't have ribosomes B. the eukaryotic ribosome is structurally different from the prokaryotic ribosome C. eukaryotes obtain ribosomes from their diet D. RNA polymerase is not essential for the viability of eukaryotes
B. the eukaryotic ribosome is structurally different from the prokaryotic ribosome
While in the lab, you perform experiments with a bacterium to determine its antibiotic susceptibility. During the course of these experiments you make the following three observations: 1) the organism is resistant to the beta-lactam antibiotic amoxicillin; 2) the organism is sensitive to augmentin, which is a co-drug of amoxicillin and clavulanic acid; 3) clavulanic acid alone has no affect on the growth or viability of the organism Based on this information, which of the following statements must be true? A. the organism does not contain any peptidoglycan B. the organism makes beta-lactamase C. the organism is a psychrotroph D. clavulanic acid is bactericidal
B. the organism makes beta-lactamase
Why are Gram-negative bacteria intrinsically resistant to vancomycin? A. they lack the target of vancomycin B. vancomycin is incapable of passing through the outer membrane C. they are capable of degrading vancomycin D. vancomycin is actively pumped into the cytoplasm of these bacteria
B. vancomycin is incapable of passing through the outer membrane
One molecule of IgG has ___ antigen-binding sites. A. 10 B. 4 C. 2 D. 0 E. 8
C. 2
Drug A has a toxic dose of 32 g/kg of body weight and a therapeutic dose of 8 g/kg of body weight. Drug B has a toxic dose of 6 g/kg of body weight and a therapeutic dose of 3 g/kg of body weight. Which of the following statements is/are true? A. Drug B is safer to use in humans than Drug A. B. Drug B has a higher chemotherapeutic index than Drug A. C. Drug A is safer to use in humans than Drug B. D. Drug A has a lower chemotherapeutic index than Drug B.
C. Drug A is safer to use in humans than Drug B.
The sensitization step of Type I hypersensitivity is characterized by the binding of the ___ region of IgE to receptors on ___. A. Fab; eosinophils B. hinge; basophils C. Fc; mast cells D. Fc; monocytes E. Fab; neutrophils
C. Fc; mast cells
A new antibiotic that would rapidly destroy endotoxin would be useful against ________ bacteria. A. commensal B. Gram-positive C. Gram-negative D. motile E. thermophilic
C. Gram-negative
In general, the degree of transplant rejection reflects the differences between donor and recipient: A. T cell receptor B. antibodies C. MHC D. bone marrow
C. MHC
Shigella species have several genes in their genome that allow for survival in acidic environments. What would you expect to happen if these genes were deleted from the Shigella chromosome? A. Shigella would be better adapted to survive in the stomach B. Shigella would no longer be able to colonize the respiratory tract C. Shigella would have a higher oral infectious dose D. Shigella would have a lower oral infectious dose E. Shigella would become an acidophile
C. Shigella would have a higher oral infectious dose
____ cells are associated with ____ immunity while ____ cells are part of ____ immunity. A. B; cell-mediated; T; innate B. T; humoral; B; cellular C. T; cell-mediated; B; humoral D. T; humoral; B; nonspecific
C. T; cell-mediated; B; humoral
Which sexually transmitted bacterial pathogen is capable of crossing the placenta and causing developmental disorders in the developing fetus? A. Haemophilus ducreyi B. Neisseria meningitidis C. Treponema pallidum D. Rickettsia rickettsia E. Listeria monocytogenes
C. Treponema pallidum
Viruses cause more illnesses on an everyday basis than do bacteria. Why are there so few antiviral agents compared to antibacterial agents? A. Viruses are a bigger problem in developing countries where they do not have the funds to develop antiviral drugs. B. Since viruses are not living, there are no drugs that can stop their proliferation. C. Viruses use functions of the host to replicate themselves, so achieving selective toxicity is difficult. D. Viruses do not cause as many deadly diseases and therefore have not been targeted with antivirals.
C. Viruses use functions of the host to replicate themselves, so achieving selective toxicity is difficult.
Nicotine in cigarette smoke paralyzes the cilia found on epithelium within the respiratory tract. The normal function of these cilia is that they: A. produce mucus that traps microorganisms. B. help to warm incoming air. C. aid in moving mucus to the nasal and oral cavities. D. contain macrophages that target microorganisms. E. provide swimming motility to epithelial cells
C. aid in moving mucus to the nasal and oral cavities.
One method of penicillin resistance is through production of beta-lactamase. This resistance method could best be described as: A. metabolic pathway alteration B. target modification C. antibiotic hydrolysis D. membrane modification E. efflux
C. antibiotic hydrolysis
Influenza A can evolve quickly into much more severe strains by mixing different chromosomal fragments in a property known as: A. antigenic camouflage B. antigenic drift C. antigenic shift D. antigenic mimicry E. antigenic tolerance
C. antigenic shift
Ultraviolet or UV light directly _____, which ultimately affects microbial viability. A. disrupts the cytoplasmic membrane B. degrades ribosomes C. causes mutations in DNA D. none of the above
C. causes mutations in DNA
_____ is a common symptom of gastroenteritis. A. fever B. coughing C. dehydration D. labored breathing E. salpingitis
C. dehydration
Bill is a nurse practitioner who was changing the bandages of his patient that was recovering from a Staphylococcus aureus skin infection. During this process, Bill left the patient's room to talk with Brenda about some administrative matters. During their chat, Bill tapped his still-gloved fingers on the desk. Once Bill left, Brenda wiped down the desk where Bill tapped his fingers with a wipe containing bleach. This would be an example of: A. pasteurization B. bacteriostasis C. disinfection D. antisepsis E. pathogenization
C. disinfection
Lyme disease is habitually present at a steady level in the New England area. Based on this, which of the following terms best describes this infectious disease? A. epidemic B. pandemic C. endemic D. noncommunicable E. nosocomial
C. endemic
Approximately 4 hours after eating potato salad at a picnic, you begin to experience projectile vomiting. This is an example of a(n) _____ that is commonly associated with ____. A. infection; rotavirus B. intoxication; Clostridium tetani C. intoxication; Staphylococcus aureus D. infection; Vibrio cholerae E. intoxication; Norovirus
C. intoxication; Staphylococcus aureus
Which of the following statements about tuberculosis is true? A. it is caused by a member of the Herpesviridae B. it is primarily a disease of the upper respiratory tract C. it is a chronic disease that is characterized by a latent, non-infectious period D. it is a vectorborne disease E. all of the above
C. it is a chronic disease that is characterized by a latent, non-infectious period
Microbial colonization within the respiratory tract is inhibited by: A. bile B. Langerhans cells C. mucociliary escalator D. sloughing off of keratin E. none of the above
C. mucociliary escalator
Vegetables, like lettuce and spinach, are often irradiated. However, eventually, these vegetables will spoil and show signs of microbial growth. This is due to the fact that irradiation only achieves: A. sterilization B. antisepsis C. sanitization D. pasteurization
C. sanitization
Clonal expansion of B cells occurs when a(n): A. antigen-presenting cell binds to a single B cell B. helper T cell secretes antibody onto a single B cell C. single B cell becomes activated when its receptor binds to a single epitope D. memory B cell attaches onto an antigen-presenting cell
C. single B cell becomes activated when its receptor binds to a single epitope
The optimal growth rate of a mesophile occurs at 37C. Suppose you incubated a mesophile at 40C, which is still within its growth range. Which of the following statements would be true about growth of a mesophile at this sub-optimal temperature? A. its generation time would decrease B. its cytoplasmic membrane would become less fluid and more rigid C. the rate of its metabolism would decrease D. its proteins would denature and unfold
C.the rate of its metabolism would decrease or D. its proteins would denature and unfold
____ is a disease that can be prevented through the use of a toxoid-based vaccine. A. rotavirus B. tetanus C. diphtheria D. B and C are correct E. none of the above
D. B and C are correct
Complement component _____ initiates the formation of the membrane attack complex. A. C3a B. C3b C. C5a D. C5b E. none of the above
D. C5b
Herd immunity is affected by ____. A. the percentage of a population that is immune B. the strength of an individual's immune system C. the proportion of susceptible and resistant individuals D. all of the above
D. all of the above
Which of the following are risk factors for contracting COVID-19? A. being above the age of 65 B. being within 3 feet of an infected individual C. having pre-existing medical conditions D. all of the above
D. all of the above
Which of the following cell types are capable of phagocytosis? A. neutrophils B. macrophages C. dendritic cells D. all of the above E. none of the above
D. all of the above
Which of the following diseases is associated with the production of a superantigen by the pathogen? A. toxic shock syndrome B. scarlet fever C. scalded skin syndrome D. all of the above E. none of the above
D. all of the above
Which of the following viruses can use the respiratory tract as a portal of entry into the body in order to establish an infection? A. rubeola virus B. varicella zoster virus C. parvovirus B19 D. all of the above E. none of the above
D. all of the above
Which of the following is not a mechanism of antibiotic resistance? A. antibiotic degradation B. target modification C. efflux pumps D. antibiotic allergy E. metabolic bypass
D. antibiotic allergy
Prior to surgery, physicians commonly apply the chemical iodine to a patient's skin. In this capacity, iodine would be considered a(n) _____. A. disinfectant B. germicide C. fungistatic D. antiseptic E. antibiotic
D. antiseptic
Exposure to antigens in the context of a vaccination is defined as ____. A. artificially acquired passive immunity B. naturally acquired active immunity C. naturally acquired passive immunity D. artificially acquired active immunity
D. artificially acquired active immunity
The clinical lab in a hospital has isolated Streptococcus pyogenes from a swab of material collected from an infected, symptomatic patient. Which of the following symptoms is the patient most likely to have? A. fever, night sweats, productive cough, chills and unexplained weight loss B. pain during urination and urethral discharge C. difficulty breathing due to the presence of an adherent pseudomembrane on the oropharynx D. high fever, sore throat with exudate and a full-body rash E. flaccid paralysis
D. high fever, sore throat with exudate and a full-body rash
All of the following statements about humoral immunity are true except: A. B cells are the primary cell type of humoral immunity B. humoral immunity is primarily effective against extracellular pathogens C. humoral immunity is characterized by antibody production D. humoral immunity is considered part of the innate immune response
D. humoral immunity is considered part of the innate immune response
All of the following statements about humoral immunity are true except: A. B cells are the primary cell type of humoral immunity B. humoral immunity is primarily effective against extracellular pathogens C. humoral immunity is characterized by antibody production D. humoral immunity is non-specific
D. humoral immunity is non-specific
Christine, a 25-year-old critical care nurse, sustained a needle stick injury while attempting to draw a blood sample from a patient chronically infected with hepatitis C virus (HCV.. Six weeks after this incident, Christine started to experience fever and other flu-like symptoms. This six-week period can best be described as the _____ phase of the infection. A. decline B. prodromal C. convalescent D. incubation E. illness
D. incubation
When Yersinia pestis remains untreated in a human body, it can enter the bloodstream and ultimately invade the ____ where it can then be transmitted person-to-person. A. liver B. spleen C. kidneys D. lungs E. large intestine
D. lungs
Psittacosis is a bacterial disease contracted by humans during contact with bacteria found in bird droppings. Human-to-human transmission is rare. Reducing contact with bird droppings will break the chain of infection by: A. reducing the virulence of the bacteria responsible for causing the disease B. affecting the bacteria's portal of entry into the human body C. reducing the number of fomites acting as vectors for the bacteria D. reducing the transmission of bacteria from the reservoir to humans E. increasing host susceptibility by altering immune status
D. reducing the transmission of bacteria from the reservoir to humans
Opsonins can best be described as: A. types of white blood cells that are especially efficient phagocytes B. types of bacterial exotoxins that destroy white blood cells C. host cells that present epitopes on MHC D. substances that enhance the process of phagocytosis
D. substances that enhance the process of phagocytosis
Which of the following statements about using killed, inactivated pathogens as a vaccine strategy is true? A. they pose a risk of reverting to virulent form that can cause disease B. they induce the strongest immune response of vaccine type, often with lifelong immunity C. they consist of only one type of antigen D. they often require booster shots to maintain sufficient immunity over time
D. they often require booster shots to maintain sufficient immunity over time
A common characteristic of all herpesviruses is their ability to: A. infect liver cells B. be transmitted by mosquitoes C. cause a skin rash D. undergo latency E. replicate in the absence of host cells
D. undergo latency
Which of the following pathogens has a complex life cycle that alternates between trophozoites and cysts? A. Chlamydia trachomatis B. Giardia intestinalis C. Naegleria fowleri D. all of the above E. B and C only
E. B and C only
This Gram-negative bacterium often occurs in outbreaks after natural disasters that can contaminate water supplies with fecal material. It does not cause fever or bloody stools but it can kill people via dehydration due to extensive watery diarrhea. Treatment is typically to keep patients hydrated for several days until the disease passes. A. Enterococcus faecalis B. Enterotoxigenic Escherichia coli C. Shigella dysenteriae D. Helicobacter pylori E. Vibrio cholerae
E. Vibrio cholerae
Which of the following factors would affect the rate of death of a bacterium when exposed to a disinfectant? A. the initial population size B. the presence of blood C. the presence of endospore-forming bacteria D. the concentration of the disinfectant E. all of the above
E. all of the above
While on vacation, Alexis decided to go swimming in the Gulf of Mexico. A few days beforehand, she had sustained a cut on her arm caused by a fall onto the sharp edge of her scooter that had not yet fully healed. While swimming, an aquatic, Gram-negative bacterium called Vibrio vulnificus entered into her bloodstream through the cut. However, 3 days later, Alexis was on her way home and never experienced any symptoms from this infection. Which of the following events contributed to elimination of Alexis' infection during this time period? A. stimulation of Toll-like receptors by Vibrio vulnificus lipopolysaccharide B. production of interleukin to activate macrophages C. activation of the complement pathway D. release of chemokines to promote extravasation of neutrophils E. all of the above
E. all of the above
Which of the following statements apply to the biphasic lifecycle of Chlamydia trachomatis? A. reticulate bodies are non-infectious B. reticulate bodes differentiate into elementary bodies C. elementary bodies are non-replicating D. reticulate bodies are found inside host cells E. all of the above are correct
E. all of the above are correct
Streptococcus mutans ferments dietary _____, which releases _____ byproducts on teeth leading to the development of dental caries. A. proteins; alkaline B. lipids; acidic C. lipids; neutral D. carbohydrates; alkaline E. carbohydrates; acidic
E. carbohydrates; acidic
____ is the most commonly reported sexually transmitted infection and is caused by an obligate intracellular bacterial pathogen. A. gonorrhea B. HIV C. syphilis D. chancroid E. chlamydia
E. chlamydia
Barry Marshall famously drank a broth culture of Helicobacter pylori to demonstrate that this bacterium causes ____. A. pseudomembranous colitis B. gastroenteritis C. typhoid fever D. dysentery E. gastric ulcers
E. gastric ulcers
Which of the following diseases would best be treated by administration of appropriate, specific antitoxin? A. gonorrhea B. whooping cough C. blastomycosis D. all of the above E. none of the above
E. none of the above
Which of the following is an arbovirus? A. norovirus B. rubeola virus C. Yersinia pestis D. hepatitis A virus E. none of the above
E. none of the above
___ is the most frequent cause of the common cold. A. coronavirus B. influenza virus C. adenovirus D. respiratory syncytial virus E. rhinovirus
E. rhinovirus
Ozaki fragments _____.
do NOT contain DNA, only RNA are NOT made of the ribosome are NOT found on the leading strand
Which of the following correctly ranks items in order from largest to smallest?
grain of rice > human skin cell > bacterial cell > virion > glucose molecule
During which phase of the growth curve are bacteria not growing due to the accumulation of waste products and depletion of available nutrients?
stationary phase