D311: Microbiology WGU OA (2025)
comprehensive questions and verified
answers ( detailed & elaborated)
ACTUAL EXAM 2025 TEST!!
A doctor prescribed antibiotics for a patient complaining of runny nose. fever. and
aches and pains. Which type of infection did the doctor suspect? - ANSWERSThe
doctor likely suspected a viral infection because antibiotics are not effective against
viral infections.
A healthcare professional is treating a patient who developed a yeast infection after
taking antibiotics. What type of medication should be prescribed to this patient? -
ANSWERSAntifungals
Which structure promotes motility in Proteus. Shigelia. and Salmonella species. all of
which can cause serious disease in humans? - ANSWERSPresence of flagella
Which bacterial virulence factor allows a strain to resist phagocytosis, increasing the
organism's virulence? - ANSWERSCapsule production
Why is treating Haemophilus influenzae difficult? - ANSWERSThe capsule is
antiphagocytic.
How do pili aid pathogens in causing disease? - ANSWERSThey cause pathogens
to adhere to host cells.
Which virulence factor allows pathogens to penetrate the dermis and invade the
body? - ANSWERSBacterial enzymes
A bacterium from a deep-sea hydrothermal vent has been cultured. Which staining
technique should be used to begin the process of species identification? -
ANSWERSGram staining
What does the presence of a clear area around a cell stained with India ink indicate
about the cell? - ANSWERSThe cell has a capsule.
How do basic stains work? - ANSWERSThe positive
What is the significance of microorganisms containing a thick coat of peptldogiywn
within the cell wall? - ANSWERSMicroorganisms containing a thick coat of
peptidoglycan within the cell wall are typically classified as gram-positive bacteria.
Why are viruses considered aceilular? - ANSWERSThey cannot reproduce without a
host.
What is the defining characteristic of eukaryotes? - ANSWERSThey have a nucleus.
, Which microorganism can cause vaginal yeast Infections and oral thrush? -
ANSWERSFungi
Why can It be difficult to determine the etiologic agent of a disease? -
ANSWERSSome signs and symptoms can be caused by many different etiologic
agents.
What kind of staining technique Is the acid-fast stain? - ANSWERS
ly charged stain is attracted to the negatively charged portion of the cell.
Which staining technique is used to distinguish bacteria based on their ability to
produce structures that can survive extreme heat stress? - ANSWERSEndospore
stain
Which aspect of a staining protocol enables dye to penetrate an endospore? -
ANSWERSHeat
Why are the relationships between pathogenic microbes and their hosts considered
parasitic? - ANSWERSThe microbe benefits from the interaction while the host is
harmed.
Which characteristic of dracunculiasis has been pivotal to the success of its
eradication campaign? - ANSWERSDracunculiasis has no animal reservoir.
Which type of organism would be most likely to grow on food stored in a refrigerator
or freezer? - ANSWERSA psychrophile would be most likely to grow on food stored
in a refrigerator or freezer as these microorganisms thrive in cold temperatures.
Staphylococcus epidermldls is a member of the human resident microbiota and
considered part of the human innate immune system. S. epldermidis uses our dead
skin cells as a source of nutrients. What type of relationship between S. epidermidis
and humans is described above? - ANSWERSThe type of relationship between
Staphylococcus epidermidis and humans described above is "Commensalism,"
where one organism (S. epidermidis) benefits (uses dead skin cells) without harming
the other organism (humans).
Commensalism
Why is the production of lactic acid by the resident microbe Lactobacillus Important
to human health? - ANSWERSLactic acid is important to human health because it
inhibits the growth of pathogenic yeasts.
Which type of infections are prevented by proper sterilization of hospital equipment
and healthcare worker handwashing? - ANSWERSNosocomial infections are
prevented by proper sterilization of hospital equipment and healthcare worker
handwashing.
comprehensive questions and verified
answers ( detailed & elaborated)
ACTUAL EXAM 2025 TEST!!
A doctor prescribed antibiotics for a patient complaining of runny nose. fever. and
aches and pains. Which type of infection did the doctor suspect? - ANSWERSThe
doctor likely suspected a viral infection because antibiotics are not effective against
viral infections.
A healthcare professional is treating a patient who developed a yeast infection after
taking antibiotics. What type of medication should be prescribed to this patient? -
ANSWERSAntifungals
Which structure promotes motility in Proteus. Shigelia. and Salmonella species. all of
which can cause serious disease in humans? - ANSWERSPresence of flagella
Which bacterial virulence factor allows a strain to resist phagocytosis, increasing the
organism's virulence? - ANSWERSCapsule production
Why is treating Haemophilus influenzae difficult? - ANSWERSThe capsule is
antiphagocytic.
How do pili aid pathogens in causing disease? - ANSWERSThey cause pathogens
to adhere to host cells.
Which virulence factor allows pathogens to penetrate the dermis and invade the
body? - ANSWERSBacterial enzymes
A bacterium from a deep-sea hydrothermal vent has been cultured. Which staining
technique should be used to begin the process of species identification? -
ANSWERSGram staining
What does the presence of a clear area around a cell stained with India ink indicate
about the cell? - ANSWERSThe cell has a capsule.
How do basic stains work? - ANSWERSThe positive
What is the significance of microorganisms containing a thick coat of peptldogiywn
within the cell wall? - ANSWERSMicroorganisms containing a thick coat of
peptidoglycan within the cell wall are typically classified as gram-positive bacteria.
Why are viruses considered aceilular? - ANSWERSThey cannot reproduce without a
host.
What is the defining characteristic of eukaryotes? - ANSWERSThey have a nucleus.
, Which microorganism can cause vaginal yeast Infections and oral thrush? -
ANSWERSFungi
Why can It be difficult to determine the etiologic agent of a disease? -
ANSWERSSome signs and symptoms can be caused by many different etiologic
agents.
What kind of staining technique Is the acid-fast stain? - ANSWERS
ly charged stain is attracted to the negatively charged portion of the cell.
Which staining technique is used to distinguish bacteria based on their ability to
produce structures that can survive extreme heat stress? - ANSWERSEndospore
stain
Which aspect of a staining protocol enables dye to penetrate an endospore? -
ANSWERSHeat
Why are the relationships between pathogenic microbes and their hosts considered
parasitic? - ANSWERSThe microbe benefits from the interaction while the host is
harmed.
Which characteristic of dracunculiasis has been pivotal to the success of its
eradication campaign? - ANSWERSDracunculiasis has no animal reservoir.
Which type of organism would be most likely to grow on food stored in a refrigerator
or freezer? - ANSWERSA psychrophile would be most likely to grow on food stored
in a refrigerator or freezer as these microorganisms thrive in cold temperatures.
Staphylococcus epidermldls is a member of the human resident microbiota and
considered part of the human innate immune system. S. epldermidis uses our dead
skin cells as a source of nutrients. What type of relationship between S. epidermidis
and humans is described above? - ANSWERSThe type of relationship between
Staphylococcus epidermidis and humans described above is "Commensalism,"
where one organism (S. epidermidis) benefits (uses dead skin cells) without harming
the other organism (humans).
Commensalism
Why is the production of lactic acid by the resident microbe Lactobacillus Important
to human health? - ANSWERSLactic acid is important to human health because it
inhibits the growth of pathogenic yeasts.
Which type of infections are prevented by proper sterilization of hospital equipment
and healthcare worker handwashing? - ANSWERSNosocomial infections are
prevented by proper sterilization of hospital equipment and healthcare worker
handwashing.
