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WGU D311 OA FINAL EXAM VERSION 2 / WGU D311 MICROBIOLOGY
OBJECTIVE ASSESSMENT FINAL EXAM NEWEST 2025/2026 ACTUAL
EXAM WITH COMPLETE QUESTIONS AND CORRECT DETAILED
ANSWERS (100% VERIFIED ANSWERS) |ALREADY GRADED A+|
||PROFESSOR VERIFIED||
The antibiotic doxycycline works by inhibiting protein synthesis
through binding to the 30S ribosomal subunit.
Why would this antibiotic be ineffective against viruses? -
ANSWER-Viruses do not have ribosomes.
A patient who is immunosuppressed develops skin pustules and
itching.
What is a plausible cause of these symptoms? - ANSWER-An
opportunistic bacterial infection
A culture of fluid collected from a healthy person via a
bronchoalveolar lavage yielded growth of Staphylococcus aureus;
however, a culture of a similarly collected sample from a person
sneezing and coughing also yielded growth of Staphylococcus
aureus.
,2|Page
How can the same bacteria cause infection and symptoms in one
person but not in another person? - ANSWER-Commensal
bacteria became opportunistic.
Why can both cats and people be infected with herpesvirus but
not infect each other? - ANSWER-These viruses are species-
specific.
Fimbria is a virulence factor of Escherichia coli necessary for an
infection to develop.
Which treatment may be helpful to prevent urinary tract infections
caused by Escherichia coli on the basis of the bacteria's virulence
factor? - ANSWER-Cranberry extract because it interferes with
the adherence of Escherichia coli to the bladder wall
A patient presents to an emergency department with severe
dehydration, diarrhea, and abdominal cramps because of the
release of exotoxin.
Which pathogen is a plausible cause of this patient's symptoms? -
ANSWER-Escherichia coli
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After a Gram staining of material collected from a skin abscess
reveals gram-positive bacteria, a physician considers
nontuberculous mycobacteriosis as a differential diagnosis.
Which stain should be applied next to further characterize these
gram-positive bacteria? - ANSWER-Acid-fast stain
A laboratory technologist sees a series of spherical structures on
a slide of swabbed material from a dog's ear canal via a
microscope with its objective set at 100x.
Which type of microorganism is this technologist seeing? -
ANSWER-Bacterium
Gram staining of a urine sample unexpectedly reveals both gram-
positive cocci and gram-negative rods; however, only gram-
negative rods are seen in white blood cells (intracellular).
How should these findings be interpreted? - ANSWER-The gram-
negative bacteria from the sample are pathogenic.
Which class of cells most often contain extrachromosomal DNA
found in plasmids? - ANSWER-Prokaryotic
, 4|Page
What is the significance of the molecule that makes up the bilayer
formed in the plasma membrane of most bacterial and eukaryotic
cells? - ANSWER-Phospholipids help maintain hydrophobic and
hydrophilic environments.
Which microorganisms produce dermatophytes that can cause
skin infections, such as athlete's foot and ringworm? - ANSWER-
Fungi
Which microorganisms can produce human pathogens that
spread via microsporidia? - ANSWER-Fungi
Why are archaea considered prokaryotic organisms? - ANSWER-
Their cells do not contain a nucleus.
Why is MRSA more pathogenic than other strains of
Staphylococcus aureus? - ANSWER-MRSA has increased
antibiotic resistance.
WGU D311 OA FINAL EXAM VERSION 2 / WGU D311 MICROBIOLOGY
OBJECTIVE ASSESSMENT FINAL EXAM NEWEST 2025/2026 ACTUAL
EXAM WITH COMPLETE QUESTIONS AND CORRECT DETAILED
ANSWERS (100% VERIFIED ANSWERS) |ALREADY GRADED A+|
||PROFESSOR VERIFIED||
The antibiotic doxycycline works by inhibiting protein synthesis
through binding to the 30S ribosomal subunit.
Why would this antibiotic be ineffective against viruses? -
ANSWER-Viruses do not have ribosomes.
A patient who is immunosuppressed develops skin pustules and
itching.
What is a plausible cause of these symptoms? - ANSWER-An
opportunistic bacterial infection
A culture of fluid collected from a healthy person via a
bronchoalveolar lavage yielded growth of Staphylococcus aureus;
however, a culture of a similarly collected sample from a person
sneezing and coughing also yielded growth of Staphylococcus
aureus.
,2|Page
How can the same bacteria cause infection and symptoms in one
person but not in another person? - ANSWER-Commensal
bacteria became opportunistic.
Why can both cats and people be infected with herpesvirus but
not infect each other? - ANSWER-These viruses are species-
specific.
Fimbria is a virulence factor of Escherichia coli necessary for an
infection to develop.
Which treatment may be helpful to prevent urinary tract infections
caused by Escherichia coli on the basis of the bacteria's virulence
factor? - ANSWER-Cranberry extract because it interferes with
the adherence of Escherichia coli to the bladder wall
A patient presents to an emergency department with severe
dehydration, diarrhea, and abdominal cramps because of the
release of exotoxin.
Which pathogen is a plausible cause of this patient's symptoms? -
ANSWER-Escherichia coli
,3|Page
After a Gram staining of material collected from a skin abscess
reveals gram-positive bacteria, a physician considers
nontuberculous mycobacteriosis as a differential diagnosis.
Which stain should be applied next to further characterize these
gram-positive bacteria? - ANSWER-Acid-fast stain
A laboratory technologist sees a series of spherical structures on
a slide of swabbed material from a dog's ear canal via a
microscope with its objective set at 100x.
Which type of microorganism is this technologist seeing? -
ANSWER-Bacterium
Gram staining of a urine sample unexpectedly reveals both gram-
positive cocci and gram-negative rods; however, only gram-
negative rods are seen in white blood cells (intracellular).
How should these findings be interpreted? - ANSWER-The gram-
negative bacteria from the sample are pathogenic.
Which class of cells most often contain extrachromosomal DNA
found in plasmids? - ANSWER-Prokaryotic
, 4|Page
What is the significance of the molecule that makes up the bilayer
formed in the plasma membrane of most bacterial and eukaryotic
cells? - ANSWER-Phospholipids help maintain hydrophobic and
hydrophilic environments.
Which microorganisms produce dermatophytes that can cause
skin infections, such as athlete's foot and ringworm? - ANSWER-
Fungi
Which microorganisms can produce human pathogens that
spread via microsporidia? - ANSWER-Fungi
Why are archaea considered prokaryotic organisms? - ANSWER-
Their cells do not contain a nucleus.
Why is MRSA more pathogenic than other strains of
Staphylococcus aureus? - ANSWER-MRSA has increased
antibiotic resistance.
