WGU D311 Microbiology Detailed Exam
Study Questions with Correct Answers
1. Which class of cells most often contain extrachromosomal DNA found in
plasmids? - ANSWER Prokaryotic
2. 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.
3. Which characteristic of mycobacterium makes a Gram stain unsuitable? -
ANSWER The cell wall has a waxy lipid.
4. Which feature of infection indicates the presence of a primary pathogen
rather than an opportunistic pathogen? - ANSWER Patients with healthy
immune systems.
5. After oral antibiotic therapy, a patient is diagnosed with vaginitis.
6. What type of microbe could be causing this opportunistic infection? -
ANSWER Fungus
7. What type of microbe is used to deliver gene therapies to human cells? -
ANSWER Virus
8. What type of diseases are found in higher numbers than expected in local
populations? - ANSWER Epidemic
,9. Which describes a mutualistic relationship? - ANSWER Ruminococcus
species using nutrients from a cow's diet to digest plant cellulose in the
rumen.
10.Why are photosynthetic bacteria and algae important to the carbon cycle on
Earth? - ANSWER Photosynthetic microbes metabolize carbon dioxide, fix
carbon, and produce oxygen.
11.What microbial process is used by bacteria and fungi to produce many
common food products, such as soy sauce, bread, and yogurt? - ANSWER
Fermentation
12.Which beneficial role do viruses have in the environment? - ANSWER
Integrating into plant genomes to increase drought tolerance.
13.A dental hygienist nicked the gum of the patient during a routine cleaning. A
mild infection of the gum was followed 10 days later with acute bacterial
endocarditis.
14.Which type of infection caused the endocarditis? - ANSWER A focal
infection
15.An infected individual riding in a subway car coughs for a few minutes, then
leaves. An individual standing at the opposite end of the car one hour after
the infected individual left develops symptoms two days later.
16.How was this pathogen transmitted? - ANSWER The pathogen exhibits
airborne transmission, where suspended mucus particles travel long
distances over time to cause infection.
,17.What is the most common portal of exit for vector-transmitted diseases such
as West Nile virus? - ANSWER Blood
18.Which type of transmission describes a parent catching the common cold
virus when caring for their sick child? - ANSWER Direct contact
transmission
19.Which microorganisms produce dermatophytes that can cause skin
infections, such as athlete's foot and ringworm? - ANSWER Fungi
20.Which microorganisms can produce human pathogens that spread via
microsporidia? - ANSWER Fungi
21.Why are archaea considered prokaryotic organisms? - ANSWER Their cells
do not contain a nucleus.
22.Why is MRSA more pathogenic than other strains of Staphylococcus
aureus? - ANSWER MRSA has increased antibiotic resistance.
23.A patient recently had an outpatient surgical procedure. After a few days at
home, they noticed swelling and redness at their incision site. How would
this infection be classified? - ANSWER Iatrogenic
24.Which viral virulence factor requires adjustments to the influenza vaccine
annually? - ANSWER Antigenic variation
25.Which pair of enzymes are produced by some bacteria that causes the
clotting of blood to protect the bacteria in the bloodstream, then a digestion
of the clots to allow the bacteria to spread? - ANSWER Coagulase and
kinase
, 26.How does coinfection of a single cell by multiple strains of a virus increase
it's pathogenicity? - ANSWER Coinfection provides the opportunity for an
antigenic shift.
Canned food is heated and sealed in sterile containers to provide a longer shelf
life and prevent spoilage. Improper canning results in the growth of
microorganisms, which may result in food containers that swell and explode.
27.Which staining technique can be used to identify these microorganisms? -
ANSWER Endospore staining
A student in a lab has just completed an endospore stain of Bacillus anthracis and
realized that heat was not applied during the staining technique.
What will the student see upon microscopic examination of the slide? - ANSWER
Pink vegetative cells with clear round areas.
A physician is given a vaginal swab in order to test for post-antibiotic vaginal
infection.
Which microscopic technique would identify opportunistic fungal pathogen? -
ANSWER Wet mount stain
A technician has just performed a Gram stain but forgot to add the safranin.
What is the likely result of this when viewed microscopically? - ANSWER Gram-
negative organisms can not be seen under the microscope.
Study Questions with Correct Answers
1. Which class of cells most often contain extrachromosomal DNA found in
plasmids? - ANSWER Prokaryotic
2. 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.
3. Which characteristic of mycobacterium makes a Gram stain unsuitable? -
ANSWER The cell wall has a waxy lipid.
4. Which feature of infection indicates the presence of a primary pathogen
rather than an opportunistic pathogen? - ANSWER Patients with healthy
immune systems.
5. After oral antibiotic therapy, a patient is diagnosed with vaginitis.
6. What type of microbe could be causing this opportunistic infection? -
ANSWER Fungus
7. What type of microbe is used to deliver gene therapies to human cells? -
ANSWER Virus
8. What type of diseases are found in higher numbers than expected in local
populations? - ANSWER Epidemic
,9. Which describes a mutualistic relationship? - ANSWER Ruminococcus
species using nutrients from a cow's diet to digest plant cellulose in the
rumen.
10.Why are photosynthetic bacteria and algae important to the carbon cycle on
Earth? - ANSWER Photosynthetic microbes metabolize carbon dioxide, fix
carbon, and produce oxygen.
11.What microbial process is used by bacteria and fungi to produce many
common food products, such as soy sauce, bread, and yogurt? - ANSWER
Fermentation
12.Which beneficial role do viruses have in the environment? - ANSWER
Integrating into plant genomes to increase drought tolerance.
13.A dental hygienist nicked the gum of the patient during a routine cleaning. A
mild infection of the gum was followed 10 days later with acute bacterial
endocarditis.
14.Which type of infection caused the endocarditis? - ANSWER A focal
infection
15.An infected individual riding in a subway car coughs for a few minutes, then
leaves. An individual standing at the opposite end of the car one hour after
the infected individual left develops symptoms two days later.
16.How was this pathogen transmitted? - ANSWER The pathogen exhibits
airborne transmission, where suspended mucus particles travel long
distances over time to cause infection.
,17.What is the most common portal of exit for vector-transmitted diseases such
as West Nile virus? - ANSWER Blood
18.Which type of transmission describes a parent catching the common cold
virus when caring for their sick child? - ANSWER Direct contact
transmission
19.Which microorganisms produce dermatophytes that can cause skin
infections, such as athlete's foot and ringworm? - ANSWER Fungi
20.Which microorganisms can produce human pathogens that spread via
microsporidia? - ANSWER Fungi
21.Why are archaea considered prokaryotic organisms? - ANSWER Their cells
do not contain a nucleus.
22.Why is MRSA more pathogenic than other strains of Staphylococcus
aureus? - ANSWER MRSA has increased antibiotic resistance.
23.A patient recently had an outpatient surgical procedure. After a few days at
home, they noticed swelling and redness at their incision site. How would
this infection be classified? - ANSWER Iatrogenic
24.Which viral virulence factor requires adjustments to the influenza vaccine
annually? - ANSWER Antigenic variation
25.Which pair of enzymes are produced by some bacteria that causes the
clotting of blood to protect the bacteria in the bloodstream, then a digestion
of the clots to allow the bacteria to spread? - ANSWER Coagulase and
kinase
, 26.How does coinfection of a single cell by multiple strains of a virus increase
it's pathogenicity? - ANSWER Coinfection provides the opportunity for an
antigenic shift.
Canned food is heated and sealed in sterile containers to provide a longer shelf
life and prevent spoilage. Improper canning results in the growth of
microorganisms, which may result in food containers that swell and explode.
27.Which staining technique can be used to identify these microorganisms? -
ANSWER Endospore staining
A student in a lab has just completed an endospore stain of Bacillus anthracis and
realized that heat was not applied during the staining technique.
What will the student see upon microscopic examination of the slide? - ANSWER
Pink vegetative cells with clear round areas.
A physician is given a vaginal swab in order to test for post-antibiotic vaginal
infection.
Which microscopic technique would identify opportunistic fungal pathogen? -
ANSWER Wet mount stain
A technician has just performed a Gram stain but forgot to add the safranin.
What is the likely result of this when viewed microscopically? - ANSWER Gram-
negative organisms can not be seen under the microscope.
