BIOD 171 Microbiology Module 5 Exam (Portage Learning)
Updated UPDATED ACTUAL Exam Questions and CORRECT
Answers | Practice Review | A+ Verified
Question 1.
What would a researcher be certain to note while analyzing a microbial sample?
Correct Answer: 1. Size and shape
2. Any observable motility
3. Gram status (positive or negative)
4. The presence of any chemical reactions
5. Changes in color localized to the organism or the surrounding media
6. Capture (or draw) images of any of the characteristics described above
Question 2.
Which non-selective yet differential agar plate should be used if a Streptococcus sample
is suspected?
Correct Answer: A BAP (blood agar plate) would be the quickest way to
identify and classify a potential streptococcus microbe based on its hemolytic
properties.
Question 3.
What disease can result if a patient with streptococcal pharyngitis goes untreated?
Correct Answer: Rheumatic fever occurs in approximately 3% of untreated
cases of streptococcal pharyngitis, presenting approximately 2-3 weeks
post-infection.
Question 4.
Streptococcus, E. coli, pseudomonas, and klebsiella are all capable of causing what
disease?
Correct Answer: All of the above foreign microbes are capable of causing
septicemia, also known as blood poisoning.
Question 5.
What is a facultative anaerobe?
Correct Answer: A facultative anaerobe is capable of growth under both
aerobic (with oxygen) and anaerobic (in the absence of oxygen) condition.
• How can Staphylococcus be differentially tested? -✓✓Staphylococcus species
are capable of growth in the presence of bile salts.
,Question 6.
A bacterial swab is taken from a patient with impetigo and streaked across an MSA
plate. Following incubation at 37C, what will be the color of the agar?
Correct Answer: The causative agent of impetigo is staph aureus, a
Gram-positive bacterium capable of fermenting mannitol. Fermentation will
lower the pH of the agar and change the dye color from red to yellow.
Question 7.
If a patient were suspected to have tuberculosis (TB), which differential stain would you
select and why?
Correct Answer: To stain for TB, one would utilize an acid-fast stain to best
visual the foreign microbe. As a mycobacterium tuberculosis would stain
poorly (indeterminate) using the Gram stain.
Question 8.
According to the module, which mycobacterium infection will be treated free of charge
by the World Health Organization (WHO)?
Correct Answer: Leprosy is completely curable using a multiple-drug therapy
regimen consisting of various combinations of the drugs dapsone, rifampin
and clofazimine—all of which is given free of charge.
Question 9.
What are the three main conditions caused by the botulism toxin?
Correct Answer: Foodborne, infant and wound. Foodborne botulism is often
the result of improperly canned, contaminated, low-acidic foods such as green
beans, corn and beats. Infant botulism occurs when children, usually under
the age of 6 months consume foods containing the bacteria. A potential
source of infant botulism is honey (which is why pediatricians recommend
avoiding feeding honey to infants) but can also be found in common places
such as soil. Wound botulism occurs when
C. botulinum bacteria colonize a deep wound, often a puncture such as those
who inject street drugs such as heroine. As contaminated needles are injected
through the skin, spores enter the body and, in the absence of oxygen,
release the toxin.
• Why are infants (< 6 months) more susceptible to botulism? -✓✓Due to
infants still maturing intestinal tract and lack of an adult microbiota, the
bacteria are able to colonize and produce the associated toxin. In adults, only
the direct ingestion of the pre-formed toxin causes disease—ingestion of C.
botulinum or the associated spores do not cause illness as a mature intestinal
microbiota sufficiently prevents bacterial germination and growth.
, Question 10.
What is the mechanism of action of the toxin produced by clostridium tentani (tetanus)?
Correct Answer: The toxin acts on inhibitory neurons causing systemic muscle
stiffness and spasms. Muscle stiffness can be observed in the jaw (lock-jaw) or
spread systemically (if left untreated) to muscles relating to respiratory
function.
Question 11.
What Gram-negative bacterium might you come into contact with in a unsanitary hot
tub?
Correct Answer: Legionella is often associated with unclean water systems
such as hot tubs, hot water tanks and AC units. Notably, legionella can only be
transmitted through water droplets small enough to be inhaled.
Question 12.
What are the three forms of plague, and what regions do they affect?
Correct Answer: Bubonic (lymph), pneumonic (lungs) and septicemic (blood).
Bubonic plague is best characterized by painfully swollen lymph nodes.
Pneumonic plague affects the respiratory system (lungs). The most rare of all
three plagues, septicemic plague targets the blood system and, if left
untreated, will develop into a life- threatening illness as the blood-borne
bacteria can infect all major organs.
Question 13.
According to the module, which STD might be best identified via dark-field microscopy?
Correct Answer: Syphilis. The causative agent, treponema pallidum, is a thin
spirochete, making Gram staining (and visualization) difficult. Treponema is
therefore most often best identified via dark-field microscopy.
Question 14.
Streptococcal Pharyngitis (Strep Throat)
Correct Answer: Streptococcus Gram-positive, round bacterium that tends to
link to other bacteria in chain-like structures
Question 15.
rheumatic fever
Correct Answer: When streptococcal pharyngitis is left untreated (3% of
cases). Gram-positive
Updated UPDATED ACTUAL Exam Questions and CORRECT
Answers | Practice Review | A+ Verified
Question 1.
What would a researcher be certain to note while analyzing a microbial sample?
Correct Answer: 1. Size and shape
2. Any observable motility
3. Gram status (positive or negative)
4. The presence of any chemical reactions
5. Changes in color localized to the organism or the surrounding media
6. Capture (or draw) images of any of the characteristics described above
Question 2.
Which non-selective yet differential agar plate should be used if a Streptococcus sample
is suspected?
Correct Answer: A BAP (blood agar plate) would be the quickest way to
identify and classify a potential streptococcus microbe based on its hemolytic
properties.
Question 3.
What disease can result if a patient with streptococcal pharyngitis goes untreated?
Correct Answer: Rheumatic fever occurs in approximately 3% of untreated
cases of streptococcal pharyngitis, presenting approximately 2-3 weeks
post-infection.
Question 4.
Streptococcus, E. coli, pseudomonas, and klebsiella are all capable of causing what
disease?
Correct Answer: All of the above foreign microbes are capable of causing
septicemia, also known as blood poisoning.
Question 5.
What is a facultative anaerobe?
Correct Answer: A facultative anaerobe is capable of growth under both
aerobic (with oxygen) and anaerobic (in the absence of oxygen) condition.
• How can Staphylococcus be differentially tested? -✓✓Staphylococcus species
are capable of growth in the presence of bile salts.
,Question 6.
A bacterial swab is taken from a patient with impetigo and streaked across an MSA
plate. Following incubation at 37C, what will be the color of the agar?
Correct Answer: The causative agent of impetigo is staph aureus, a
Gram-positive bacterium capable of fermenting mannitol. Fermentation will
lower the pH of the agar and change the dye color from red to yellow.
Question 7.
If a patient were suspected to have tuberculosis (TB), which differential stain would you
select and why?
Correct Answer: To stain for TB, one would utilize an acid-fast stain to best
visual the foreign microbe. As a mycobacterium tuberculosis would stain
poorly (indeterminate) using the Gram stain.
Question 8.
According to the module, which mycobacterium infection will be treated free of charge
by the World Health Organization (WHO)?
Correct Answer: Leprosy is completely curable using a multiple-drug therapy
regimen consisting of various combinations of the drugs dapsone, rifampin
and clofazimine—all of which is given free of charge.
Question 9.
What are the three main conditions caused by the botulism toxin?
Correct Answer: Foodborne, infant and wound. Foodborne botulism is often
the result of improperly canned, contaminated, low-acidic foods such as green
beans, corn and beats. Infant botulism occurs when children, usually under
the age of 6 months consume foods containing the bacteria. A potential
source of infant botulism is honey (which is why pediatricians recommend
avoiding feeding honey to infants) but can also be found in common places
such as soil. Wound botulism occurs when
C. botulinum bacteria colonize a deep wound, often a puncture such as those
who inject street drugs such as heroine. As contaminated needles are injected
through the skin, spores enter the body and, in the absence of oxygen,
release the toxin.
• Why are infants (< 6 months) more susceptible to botulism? -✓✓Due to
infants still maturing intestinal tract and lack of an adult microbiota, the
bacteria are able to colonize and produce the associated toxin. In adults, only
the direct ingestion of the pre-formed toxin causes disease—ingestion of C.
botulinum or the associated spores do not cause illness as a mature intestinal
microbiota sufficiently prevents bacterial germination and growth.
, Question 10.
What is the mechanism of action of the toxin produced by clostridium tentani (tetanus)?
Correct Answer: The toxin acts on inhibitory neurons causing systemic muscle
stiffness and spasms. Muscle stiffness can be observed in the jaw (lock-jaw) or
spread systemically (if left untreated) to muscles relating to respiratory
function.
Question 11.
What Gram-negative bacterium might you come into contact with in a unsanitary hot
tub?
Correct Answer: Legionella is often associated with unclean water systems
such as hot tubs, hot water tanks and AC units. Notably, legionella can only be
transmitted through water droplets small enough to be inhaled.
Question 12.
What are the three forms of plague, and what regions do they affect?
Correct Answer: Bubonic (lymph), pneumonic (lungs) and septicemic (blood).
Bubonic plague is best characterized by painfully swollen lymph nodes.
Pneumonic plague affects the respiratory system (lungs). The most rare of all
three plagues, septicemic plague targets the blood system and, if left
untreated, will develop into a life- threatening illness as the blood-borne
bacteria can infect all major organs.
Question 13.
According to the module, which STD might be best identified via dark-field microscopy?
Correct Answer: Syphilis. The causative agent, treponema pallidum, is a thin
spirochete, making Gram staining (and visualization) difficult. Treponema is
therefore most often best identified via dark-field microscopy.
Question 14.
Streptococcal Pharyngitis (Strep Throat)
Correct Answer: Streptococcus Gram-positive, round bacterium that tends to
link to other bacteria in chain-like structures
Question 15.
rheumatic fever
Correct Answer: When streptococcal pharyngitis is left untreated (3% of
cases). Gram-positive
