Microbiology Program Quizzes

Which of the following is a feature unique to prokaryotic cells?

A. they have a cell wall

B. they have circular DNA

C. they are unicellular organisms

D. they lack ribosomes

B. they have circular DNA

What characteristic makes ager a useful culture medium?

A. it is lipid at room temperature

B. it is resistant to contamination by fungi

C. it cannot be digested by most microorganisms

D. it both melts and solidifies at 100 degrees C

C. it cannot be digested by most microorganisms

Who first used pure cultures to establish the cause of microbial diseases?

A. Robert Koch

B. Antonie van Leeuwenhoek

C. Joseph Lister

D. Louis Pasteur

A. Robert Koch

Which of the following contains LPS (lipopolysaccharides), which forms the basis of endotoxins?

A. both gram-positive and gram-negative cells

B. gram-positive cells

C. gram-negative cells

D. fungi

C. gram-negative cells

Bacilli can be described as having what shape?

A. spherical

B. spiral

C. spring

D. rod

D. rod

Which two bacteria genera are spore-forming?

A. Bacillus and Clostridium

B. Staphylococcus and Streptococcus

C. Neisseria and Mycobacteria

D. Escherichia and Salmonella

A. Bacillus and Clostridium

Which of the following describes a plasmid?

A. it is an extrachromosomal DNA for antibiotic resistance

B. it is a single stranded extrachromosomal RNA for toxin resistance

C. it is an extrachromosomal DNA for heat resistance

D. it is a single-stranded DNA for dehydration resistance

A. it is an extrachromosomal DNA for antibiotic resistance

Which of the following bacterial structures is MOST involved in adherence?

A. capsule

B. lipopolysaccharide

C. ordinary pili

D. O-specific side-chain

C. ordinary pili

All of the following procedures are useful for the diagnosis of fungal infection EXCEPT which?

A. serology test

B. gram stain test

C. direct microscopic examination

D. culture fungi on Sabouraud's ager

B. gram stain test

Why are gram-negative bacteria more resistant to antimicrobial agents (compared with gram-positive bacteria)?

A. the peptidoglycan layer in gram-negative bacteria is thicker

B. there is an outer membrane

C. all medically important gram-negative bacteria form endospores

D. a capsule forms a physical barrier in all gram-negative bacteria

B. there is an outer membrane

Which of the following stains is considered differential?

A. capsule stain

B. crystal violet

C. malachite green

D. acid-fast stain

D. acid-fast stain

If a process kills 90% of the organisms per minute, how many minutes would it take to kill all organisms when starting with 10,000 organisms?

A. 5 minutes

B. 6 minutes

C. 4 minutes

D. 3 minutes

A. 5 minutes

Koch's postulates are used for which of the following purposes?

A. To determine if a given organism causes the given disease

B. to determine if the given organism is a bacterium or a fungus

C. to determine an organism's growth requirements

D. to determine if a given organism will produce an immune response

A. To determine if a given organism causes the given disease

Why would a flagellated strain be more virulent than a nonflagellated strain?

A. flagella can kill the white blood cells

B. flagella allow the bacteria to negotiate in the mucus layers protecting body surfaces

C. flagella give metabolic advantage to the bacterium

D. flagella are major adhesive structures

B. flagella allow the bacteria to negotiate in the mucus layers protecting body surfaces

What is the type of virus replication where the virus remains dormant in the host cell called?

A. Lytic cycle

B. Lysogenic cycle

C. Abortive infection

D. Subclinical infection

B. Lysogenic cycle

Bacterial cells reproduce by what mechanism?

A. spore formation

B. binary fission

C. sexual reproduction

D. fusion

B. binary fission

Which of the following best describes a capsomer?

A. a viral inclusion body

B. the lipid envelope

C. a protein spike

D. part of a viral capsid

D. part of a viral capsid

Which of the following is characterized by possessing a thick layer of peptidoglycan?

A. all bacteria

B. all viruses

C. gram-positive bacteria

D. gram-negative bacteria

C. gram-positive bacteria

A 27-year-old man went to the hospital for a deep laceration on his foot that he received during his construction job. He received a shot for a specific type of organism. This organism is classified as which of the following?

A. gram-positive cocci, ferments lactose

B. gram-positive rod, anaerobic, and spore forming

C. gram-negative bacilli, aerobic, and spore forming

D. it is difficult to stain with gram stain

B. gram-positive rod, anaerobic, and spore forming

Acute rheumatic fever is a nonsuppurative complication that follows infection by which of the following organisms?

A. Streptococcus pneumoniae

B. Streptococcus pyogenes

C. Enterococcus faecalis

D. Salmonella typhi

B. Streptococcus pyogenes

Following a barbecue hosted by a hunter who served "pork hamburgers", several guests developed abdominal pain and diarrhea. Their condition progresses about a week later to fever, myalgia, and periorbital edema. Blood analysis shows an increased eosinophil count. Which of the following is the most likely cause of these symptoms?

A. Anthrax

B. Botulism

C. Escherichia coli gastroenteritis

D. Trichinosis

D. Trichinosis

All of the following agents cause opportunistic infection in AIDS patients except for:

A. Candida

B. cytomegalovirus

C. Plasmodium

D. Mycobacterium avium-intercellular

C. Plasmodium

Negri bodies are the major pathological changes seen in which disease?

A. rabies

B. bronchiolitis

C. croup

D. AIDS

A. rabies

A "slapped cheek" rash in children is characteristic of which disease?

A. papillomavirus

B. measles virus

C. chickenpox

D. parvovirus B19

D. parvovirus B19

A 31-year-old woman with systemic lupus erythematosus (SLE) is found to have a positive serologic test for syphilis (VDRL test). She denies having had sexual contact with a partner who had symptoms of a venereal disease. What would be the next best step to confirm a venereal syphilitic disease?

A. reassure her that the test is a false-positive reaction for autoimmune disease

B. trace her sexual contact for serological testing

C. refer her to a physician to prescribe tetracycline as an antibiotic

D. perform a fluorescent treponemal antibody-absorbed (FTA-ABS) test

D. perform a fluorescent treponemal antibody-absorbed (FTA-ABS) test

Which is NOT an organism that is transmitted by larva or cercaria that penetrates the skin?

A. Ancylostoma duodenale

B. Strongyloides stercoralis

C. Wuchereria bancrofti

D. Schistosoma haematobium

C. Wuchereria bancrofti

Poliovirus replicates in and causes damage to which of the following structures?

A. sensory neuron (dorsal horn of the spinal cord)

B. motor neuron (anterior or ventral horn of the spinal cord)

C. skeletal muscle fibers

D. cardiac muscle fibers

B. motor neuron (anterior or ventral horn of the spinal cord)

Which of the following organisms does NOT cross the placental barrier and cause congenital defects in humans?

A. cytomegalovirus

B. Toxoplasma gondii

C. rubella virus

D. herpes simplex virus, type 2

D. herpes simplex virus, type 2

What is the most commonly reported tick-borne disease seen in the United States?

A. AIDS

B. Lyme disease

C. Rocky Mountain spotted fever

D. syphilis

B. Lyme disease

Neisseria meningitidis uses which of the following virulence factors to survive its passage from the blood to the meninges?

A. flagellum

B. pilus

C. pyrogenic exotoxin

D. polysaccharide capsule

D. polysaccharide capsule

Which of the following has been implicated in hemolytic uremic syndrome (HUS)?

A. Salmonella typhi

B. Escherichia coli

C. Salmonella enteritidis

D. Vibrio cholerae

B. Escherichia coli

The acid-fast stain is used to identify which of the following types of microorganism?

A. genus Treponema

B. genus Mycoplasma

C. genus Mycobacterium

D. genus Corynebacterium

C. genus Mycobacterium

Which of the following has been implicated in peptic ulcer disease?

A. Mycobacterium

B. Listeria

C. Helicobacter

D. Corynebacterium

C. Helicobacter

Which virus is most characterized by a bullet-shaped capsid?

A. Ebola

B. influenza

C. rabies

D. measles

C. rabies

Which of the following is the causative agent of genital herpes?

A. bacterium

B. fungus

C. virus

D. parasitic worm

C. virus

In cases of meningitis, in which age group is Neisseria meningitidis most often implicated?

A. newborns

B. 3 years to six years

C. young adults, college age

D. older adults, elderly

C. young adults, college age

The most common cause of skin lesions such as boils or abscesses is which of the following bacteria?

A. Streptococcus pneumoniae

B. Staphylococcus aureus

C. Bacillus cereus

D. Listeria monocytogenes

B. Staphylococcus aureus

Which of the following water borne enteric diseases is characterized by massive amounts of fluids passed in the feces?

A. salmonellosis

B. cholera

C. hepatitis A

D. E. coli enteritis

B. cholera

Which of the following describes the typical appearance of sputum in the patients with pneumonia due to Klebsiella pneumoniae?

A. sputum is purulent and rusty color

B. sputum is thin and watery

C. sputum is bloody and gelatinous

D. scant amount of sputum

C. sputum is bloody and gelatinous

If a patient is complaining of chest pain, fever, dry cough, and some confusion and has diarrhea and abdominal pain, which of the following organisms is most likely to be the pathogen?

A. Bordetella pertussis

B. Legionella pneumophila

C. Mycobacterium tuberculosis

D. Streptococcus pneumoniae

B. Legionella pneumophila

Antigenic drift seen in influenza is responsible for which of the following epidemiologic phenomenon?

A. a patient who had suffered from influenza previously has partial immunity to the new influenza virus

B. a patient who had suffered from influenza previously has no immunity against the new influenza virus

C. a patient who had suffered from influenza previously has a booster effect to his or her immunity

D. there is no effect on the immunity of a previously infected patient

A. a patient who had suffered from influenza previously has partial immunity to the new influenza virus

Which of the following fungi cause granulomas in the lung that are mistaken for tuberculosis?

A. Histoplasma capsulatum

B. Blastomyces dermatitidis

C. Coccidioides immitis

D. Pneumocystis carinii

A. Histoplasma capsulatum

Which of the following could cause hemolytic uremic syndrome?

A. enterohemorrhagic E. coli

B. enteroaggregative E. coli

C. enteropathogenic E. coli

D. enterotoxigenic E. coli

A. enterohemorrhagic E. coli

Which of the following is one of the characteristics of food intoxication due to preformed toxins?

A. very long incubation period

B. very short incubation period

C. live bacteria must be ingested in the food

D. only cold foods are involved in transmitting this disease

B. very short incubation period

In which of the following tissues would the larvae of Trichinella spiralis be commonly found?

A. striated muscle

B. brain

C. bones

D. lungs

A. striated muscle

In which of the parasitic infections does the filariform larvae directly penetrate through the skin to infect a new host?

A. common round worm

B. whipworm

C. hookworm

D. thread worm

C. hookworm

Which of the following causes Whitlow, a lesion commonly seen on the fingers of nurses?

A. papillomavirus

B. adenovirus

C. herpes simplex

D. rubella

C. herpes simplex

Which of the following causes erythema infectiosum?

A. measles virus

B. varicella zoster virus

C. parvovirus B19

D. herpes virus type 6

C. parvovirus B19

What is the etiologic agent that causes a patient to have a high fever, malaise, and either pneumonia or painful, swollen lymph nodes called "bubos"?

A. Yersinia pestis

B. Shigella sonneri

C. Yersinia enterocolitica

D. Vibrio cholerae

A. Yersinia pestis

Which of the following diseases is NOT one of the childhood exanthems?

A. measles

B. mumps

C. rubella

D. rubeola

B. mumps

Pertussis can be a serious life-threatening disease due to what bacterial effect on the respiratory system?

A. swelling of the epiglottis

B. formation of a pseudomembrane

C. destruction of the mucociliary action of the respiratory epithelium

D. pneumonia

C. destruction of the mucociliary action of the respiratory epithelium

Which type of virus possesses a double-stranded RNA and a double capsid?

A. reovirus

B. flavivirus

C. retrovirus

D. alphavirus

A. reovirus

Trypanosoma cruzi causes which of the following diseases?

A. African sleeping sickness

B. toxoplasmosis

C. Chagas disease

D. leishmania

C. Chagas disease

Tinea unguium is a fungal infection of what part of the body?

A. scalp

B. between the toes

C. nails

D. groin

C. nails

Which of the following is a gram-negative, oxidase-positive, facultative anaerobe?

A. Escherichia coli

B. Klebsiella pneumoniae

C. Pseudomonas aeruginosa

D. Haemophilus influenzae

D. Haemophilus influenzae

A patient complains of diarrhea, abdominal pain, and flatulence shortly after returning from a rafting trip in Canada. He admits drinking water from the streams. With what flagellate protozoan is he most likely infected?

A. Giardia lamblia

B. Toxoplasmosis gondii

C. Entamoeba histolytica

D. Leishmania donovani

A. Giardia lamblia

Which term refers to an "infection that is acquired in a hospital"?

A. zoonosis

B. fomite

C. nosocomial

D. septicemia

C. nosocomial

Filaria parasites are transmitted by what means?

A. ingestion

B. arthropod bite

C. sexual contact

D. penetration through the skin

B. arthropod bite

A patient presents with a high fever, pharyngitis, lymphadenopathy, and lymphocytosis with atypical lymphocytes. Which infectious disease do the signs and symptoms BEST characterize?

A. fifth disease

B. shingles

C. parainfluenza

D. infectious mononucleosis

D. infectious mononucleosis

Which virus is currently the only poxvirus that causes disease in humans, which appears as papules and nodules on the skin?

A. variola major

B. vaccinia

C. poxvirus of molluscum contagiosum

D. varicella zoster

C. poxvirus of molluscum contagiosum

Which of the following is NOT a causative agent of the common cold?

A. adenovirus

B. rhinovirus

C. coronavirus

D. hantavirus

D. hantavirus

Pharyngitis with a diffuse erythematous rash appearing on the head and extremities and the appearance of a "strawberry tongue" is descriptive of what disease?

A. scarlet fever

B. rheumatic fever

C. pyoderma

D. toxic shock syndrome

A. scarlet fever

Which correctly describes the appearance of Staphylococcus under the microscope?

A. gram-negative cocci in clusters

B. gram-positive cocci in clusters

C. gram-negative cocci in short chains

D. gram-positive cocci in short chains

B. gram-positive cocci in clusters

Bacteria are often cultured on blood agar to detect the presence of hemolytic cytotoxins. What type of hemolysis is beta-hemolysis?

A. no hemolysis is detected

B. incomplete hemolysis on blood agar

C. complete hemolysis

D. irregular hemolysis

C. complete hemolysis

When Staphylococcus aureus enters the blood and is carried to the bone, it causes an infection given what name?

A. osteonecrosis

B. osteopenia

C. osteolysis

D. osteomyelitis

D. osteomyelitis

Which food-borne disease is MOST associated with home canning?

A. botulism

B. cholera

C. listerosis

D. typhoid fever

A. botulism

The Mantoux test is used to detect prior infection by which agent?

A. Clostridium difficile

B. Mycobacterium tuberculosis

C. Mycobacterium leprae

D. Cornybacterium diphtheriae

B. Mycobacterium tuberculosis

Select the TRUE statement concerning rabies.

A. the incubation phase is very short; approximately 2 to 10 days

B. it is caused by a coronavirus

C. it is an encephalitis with neuron degeneration

D. it is a spongiform encephalitis caused by a prion

C. it is an encephalitis with neuron degeneration

A finding of gram-positive encapsulated diplococci in sputum is indicative of what organism?

A. Escherichia coli

B. Pseudomonas aeruginosa

C. Streptococcus pneumoniae

D. Neisseria gonorrhoeae

C. Streptococcus pneumoniae

What term is defined as a "symbiotic relationship in which one partner benefits and the other is unaffected'?

A. commensalism

B. parasitism

C. mutualism

D. antagonism

A. commensalism

In human beings, the most common habitat of Staphylococcus aureus is the:

A. throat

B. urethra

C. skin

D. nasal chamber

D. nasal chamber

What clinical sign can usually diagnose many childhood diseases caused by viral infections of the upper respiratory tract?

A. type of rash

B. type of cough

C. type of fever

D. incubation period

A. type of rash

Otitis media and sinusitis are usually preceded by what infection?

A. middle ear infection

B. infection with Pseudomonas

C. nasopharyngeal infection

D. lower respiratory tract infection

C. nasopharyngeal infection

In adults, about 60% of the bacterial pneumonias that require hospitalization are caused by what organism?

A. Mycoplasma pneumoniae

B. Streptococcus pneumoniae

C. Staphylococcus aureus

D. Klebsiella pneumonia

B. Streptococcus pneumoniae

During which stage of syphilis is the patient noninfectious?

A. first stage (primary syphilis)

B. second stage (secondary syphilis)

C. third stage (tertiary syphilis)

D. fourth stage (quaternary syphilis)

C. third stage (tertiary syphilis)

When epidemics of bacterial meningitis occur, they usually involve which organism?

A. Neisseria meningitidis

B. Streptococcus pneumoniae

C. Haemophilus influenzae

D. Streptococcus pyogenes

A. Neisseria meningitidis

What is the most common etiological agent(s) causing subacute bacterial endocarditis?

A. Streptococcus pyogenes

B. Pseudomonas aeruginosa

C. normal skin or mouth flora

D. Escherichia coli

C. normal skin or mouth flora

Symptoms of AIDS appear when

A. CD4 counts are <300/ul of blood

B. CD4 counts are >900/ul of blood

C. CDS counts are >1000/ul of blood

D. CD8 counts are <700/ul of blood

A. CD4 counts are <300/ul of blood

Which of the following is the most effective way to sterilize heat-sensitive liquids?

A. autoclave

B. filtration

C. iodine

D. freezing

B. filtration

Which term is defined as the "spread of disease from parent to offspring"?

A. nosocomial transmission

B. horizontal transmission

C. vertical transmission

D. vector transmission

C. vertical transmission

Which of the following is NOT a communicable infectious disease?

A. chickenpox

B. tetanus

C. hepatitis B

D. influenza

B. tetanus

Which precautions would be appropriate to prevent the spread of tuberculosis from an infected patient?

A. gowns and gloves are necessary

B. proper disposal of urine- or feces-contaminated items

C. wear masks and disinfect items contaminated with saliva

D. no special precautions are warranted

C. wear masks and disinfect items contaminated with saliva

Which of the following epidemiologic terms is defined as the "ratio between the number of new cases of a disease divided by the number of healthy individuals in a population"?

A. incidence

B. prevalence

C. morbidity rate

D. mortality rate

A. incidence

A disease that occurs with relative regularity only in the southwestern United States would be described as having what type of disease occurrence?

A. pandemic

B. epidemic

C. sporadic

D. endemic

D. endemic

In 2003, the first cases of severe acute respiratory syndrome (SARS) were reported in Asia. Soon, many cases were reported from four continents. How would this spread of SARS be classified?

A. an outbreak

B. an epidemic

C. sporadic cases

D. a pandemic

D. a pandemic

Which is a term that refers to a disease that is primarily an infection of animals and is accidentally transmitted to humans?

A. sporadic

B. secondary infection

C. zoonosis

D. reservoir

C. zoonosis

A patient you treated in the morning has influenza, a viral illness caused by an enveloped RNA virus. Which of the following methods of infection control should you use for your adjusting table?

A. sterilization

B. pasteurization

C. high-level disinfectant

D. intermediate-level disinfectant

D. intermediate-level disinfectant

Which of the following terms describes an epidemiological study where exposed and non-exposed populations are identified and followed over time?

A. cohort study

B. case-control study

C. descriptive study

D. cross-sectional study

A. cohort study

Which of the following rates is calculated by dividing all current cases of a disease (old and new) by the total population?

A. incidence rate

B. prevalence rate

C. attack rate

D. case-fatality rate

B. prevalence rate

The term used to describe the occurrence of a disease in a geographic area all the time is:

A. epidemic

B. pandemic

C. epizoodemic

D. endemic

D. endemic

The number of new cases of a specific disease within a specific time period in a given population is called the:

A. prevalence

B. epidemic

C. mortality rate

D. incidence

D. incidence

The single most important measure to prevent the spread of infectious diseases is:

A. handwashing

B. proper cooking

C. canning

D. pasteurization

A. handwashing

The period of time between exposure to an infectious agent and the onset of disease signs and symptoms is called the:

A. prodromal period

B. incubation period

C. acute phase

D. chronic phase

B. incubation period

Eating undercooked pork is associated with an increased risk of infection with which of the following?

A. Trichinella

B. Escherichia

C. Salmonella

D. Staphylococcus

A. Trichinella

Which of the following is TRUE of botulism?

A. it is a viral infection

B. it is spread by mosquitoes

C. it is sexually transmitted

D. it is caused by a toxin

D. it is caused by a toxin

What is the major cause of death in the United States?

A. respiratory infections

B. enteric disease

C. lifestyle conditions

D. lack of prenatal care

C. lifestyle conditions

Indicator organisms are used in water testing for the purpose of detecting which of the following?

A. fecal contamination

B. turbidity levels

C. presence of absence of chemicals

D. offensive odors

A. fecal contamination

Which of the following does NOT describe ground-level ozone?

A. contributes to smog formation

B. protects the earth from UV radiation

C. involves sulfur dioxide reactions

D. involves nitrogen oxide reactions

B. protects the earth from UV radiation

Which of the following causes anthracosis?

A. anthrax

B. asbestos

C. silica

D. coal dust

D. coal dust

Water that contains harmful chemicals is called:

A. contaminated water

B. polluted water

C. potable water

D. deionized water

B. polluted water