D311 MICROBIOLOGY WGU OA
COMPREHENSIVE EXAM QUESTIONS AND
CORRECT ANSWERS STUDY GUIDE
●● Which environment would contain microbes that are psychrophilic?
Answer: Glaciers
●● What is the role of nematodes in soil?
Answer: They photosynthesize and fix nitrogen.
●● Which eukaryote is responsible for producing antibiotics to ward off
bacterial competitors?
Answer: Fungi
●● Which symbiotic relationship is an example of mutualism?
Answer: The relationship between humans and the Escherichia coli
colonizing the human gut
●● Which type of symbiotic relationship exists between the Escherichia
coli (E. coli) that inhabit the human gut and the humans who utilize the
vitamin K produced by E. coli?
Answer: Mutualism
,●● Which description of resident microbiota is true?
Answer: Resident microbiota constantly live on the human body.
●● Which relationship is exhibited by intestinal Escherichia coli and
their human host?
Answer: Mutualism
●● Which type of disease is transmitted from animals to humans?
Answer: Zoonotic diseases
●● Which type of disease is acquired in hospital settings?
Answer: Nosocomial diseases
●● Which portal of exit can expel the most viral particles?
Answer: Respiratory
●● Which type of disease is sickle cell anemia?
Answer: Noninfectious
●● Which type of transmission occurs when tuberculosis is spread
through small particles expelled by a cough?
Answer: Droplet transmission
,●● Which type of transmission occurs when pathogens are spread from
mother to child during breastfeeding?
Answer: Vertical direct contact transmission
●● Which type of transmission occurs when an arthropod carries a viral
pathogen inside of its body?
Answer: Biological vector transmission
●● Which type of transmission occurs through contact with a fomite?
Answer: Indirect contact transmission
●● Which infected host would be considered a passive carrier?
Answer: A healthcare professional who does not wash their hands after
seeing an infected patient
●● How is Giardia lamblia, the causative agent of giardiasis,
transmitted?
Answer: Contaminated food or water
●● Which organism is the definitive host of Toxoplasma gondii?
Answer: Birds
●● Which disease is transmitted by animals but not arthropods?
, Answer: Rabies
●● How can adhesins be described?
Answer: Adhesins found on the surface of pathogens bind to receptors of
host cells.
●● Which description indicates a portal of entry?
Answer: Body features through which pathogens can enter host tissue
●● Pathogens produce proteins to prevent the fusion of the phagosome
and the lysosome (phagolysosome).Why does this virulence factor
facilitate invasion?
Answer: It prevents the exposure of pathogens to lethal digestive
enzymes.
●● Which action refers to a secondary infection?
Answer: An infection by one pathogen enables another pathogen to
cause an infection.
●● What differentiates signs from symptoms of disease?
Answer: Signs are measurable; symptoms are subjective.
●● Which procedure does a clinician use to measure a symptom?
COMPREHENSIVE EXAM QUESTIONS AND
CORRECT ANSWERS STUDY GUIDE
●● Which environment would contain microbes that are psychrophilic?
Answer: Glaciers
●● What is the role of nematodes in soil?
Answer: They photosynthesize and fix nitrogen.
●● Which eukaryote is responsible for producing antibiotics to ward off
bacterial competitors?
Answer: Fungi
●● Which symbiotic relationship is an example of mutualism?
Answer: The relationship between humans and the Escherichia coli
colonizing the human gut
●● Which type of symbiotic relationship exists between the Escherichia
coli (E. coli) that inhabit the human gut and the humans who utilize the
vitamin K produced by E. coli?
Answer: Mutualism
,●● Which description of resident microbiota is true?
Answer: Resident microbiota constantly live on the human body.
●● Which relationship is exhibited by intestinal Escherichia coli and
their human host?
Answer: Mutualism
●● Which type of disease is transmitted from animals to humans?
Answer: Zoonotic diseases
●● Which type of disease is acquired in hospital settings?
Answer: Nosocomial diseases
●● Which portal of exit can expel the most viral particles?
Answer: Respiratory
●● Which type of disease is sickle cell anemia?
Answer: Noninfectious
●● Which type of transmission occurs when tuberculosis is spread
through small particles expelled by a cough?
Answer: Droplet transmission
,●● Which type of transmission occurs when pathogens are spread from
mother to child during breastfeeding?
Answer: Vertical direct contact transmission
●● Which type of transmission occurs when an arthropod carries a viral
pathogen inside of its body?
Answer: Biological vector transmission
●● Which type of transmission occurs through contact with a fomite?
Answer: Indirect contact transmission
●● Which infected host would be considered a passive carrier?
Answer: A healthcare professional who does not wash their hands after
seeing an infected patient
●● How is Giardia lamblia, the causative agent of giardiasis,
transmitted?
Answer: Contaminated food or water
●● Which organism is the definitive host of Toxoplasma gondii?
Answer: Birds
●● Which disease is transmitted by animals but not arthropods?
, Answer: Rabies
●● How can adhesins be described?
Answer: Adhesins found on the surface of pathogens bind to receptors of
host cells.
●● Which description indicates a portal of entry?
Answer: Body features through which pathogens can enter host tissue
●● Pathogens produce proteins to prevent the fusion of the phagosome
and the lysosome (phagolysosome).Why does this virulence factor
facilitate invasion?
Answer: It prevents the exposure of pathogens to lethal digestive
enzymes.
●● Which action refers to a secondary infection?
Answer: An infection by one pathogen enables another pathogen to
cause an infection.
●● What differentiates signs from symptoms of disease?
Answer: Signs are measurable; symptoms are subjective.
●● Which procedure does a clinician use to measure a symptom?
