BIOD 171 MODULE 5 EXAM QUESTIONS AND
ANSWERS LATEST 2025-2026 UPDATE
What are the three main conditions caused by the botulism toxin? -
Answer-Foodborne, infant, and wound
Foodborne botulism cause - Answer-Foodborne botulism is often the
result of improperly canned, contaminated, low-acidic foods such as
green beans, corn, and beats
Infant botulism cause - Answer-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
Why do pediatricians recommend avoiding feeding honey to infants? -
Answer-Honey is a potential source of infant botulism
Wound botulism cause - Answer-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, int he absence
of oxygen, release the toxin
Why are infants (<6 months) more susceptible to botulism? - Answer-
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
What is the mechanism of action of the toxin produced by clostridium
tetani (tetanus)? - 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
What gram-negative bacterium might you come into contact with in an
unsanitary hot tub? - 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
What are the three forms of plague, and what regions do they affect? -
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.
According to the module, which STD might be best identified via dark-
field microscopy? - Answer-Syphilis. The causative agent, treponema
pallidum, is a thin spirochete, making Gram staining (and visualization)
ANSWERS LATEST 2025-2026 UPDATE
What are the three main conditions caused by the botulism toxin? -
Answer-Foodborne, infant, and wound
Foodborne botulism cause - Answer-Foodborne botulism is often the
result of improperly canned, contaminated, low-acidic foods such as
green beans, corn, and beats
Infant botulism cause - Answer-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
Why do pediatricians recommend avoiding feeding honey to infants? -
Answer-Honey is a potential source of infant botulism
Wound botulism cause - Answer-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, int he absence
of oxygen, release the toxin
Why are infants (<6 months) more susceptible to botulism? - Answer-
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
What is the mechanism of action of the toxin produced by clostridium
tetani (tetanus)? - 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
What gram-negative bacterium might you come into contact with in an
unsanitary hot tub? - 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
What are the three forms of plague, and what regions do they affect? -
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.
According to the module, which STD might be best identified via dark-
field microscopy? - Answer-Syphilis. The causative agent, treponema
pallidum, is a thin spirochete, making Gram staining (and visualization)
