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D311: Microbiology WGU OA 2025 Questions
With Correct Answers.
What is a characteristic of rhizospheres? - .....ANSWER
...✔✔ The rhizosphere is where plants release
organic compounds that can be metabolized by
microbes into soil.
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
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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
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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
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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.
D311: Microbiology WGU OA 2025 Questions
With Correct Answers.
What is a characteristic of rhizospheres? - .....ANSWER
...✔✔ The rhizosphere is where plants release
organic compounds that can be metabolized by
microbes into soil.
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
,2|Page
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
,3|Page
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
, 4|Page
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.
