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BIO 250 FINAL EXAM QUESTIONS AND
ANSWERS 2025
which of the following is used to sterilize items that should not,
or cannot, be exposed to heat or water? - correct answer-
ethylene oxide
A scientist develops a new medication that is a protein
compound and that must be administered by injection. Which of
the following would be the most effective and safest means of
preparing a sterile solution of the new medication? - correct
answer- filtration
Why are endospores used to measure the effectiveness of
autoclave sterilization? - correct answer- endospores are very
hard to destroy
which of the following is an example of pasteurization? - correct
answer- heat is used to kill potential pathogens in apple juice
which is CORRECT regarding the rate of microbial death? -
correct answer- cells in a culture die at a constant rate?
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which of the following factors will influence the action of
antimicrobial agents? - correct answer- - the number of
microorganisms
-the type of microorganisms present
- temperature and ph
- mode and dosage of the agent
which of the following is NOT a target of drugs that inhibit
protein synthesis? - correct answer- interference with alanine -
alanine bridges in tetrapeptide
an antibiotic is - correct answer- a naturally occurring
compound that kills microbes or inhibits their growth
An antimicrobial that inhibits cell wall synthesis will result in
which of the following? - correct answer- cells become more
susceptible to osmotic pressure
which of the following is NOT an approach to combat drug-
resistant bacteria? - correct answer- flood a patients system
with healthy bacteria to quickly remove access to nutrients and
starve the pathogen
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the mechanism of action of the antibiotic rifampin (used to treat
tuberculosis infections) is - correct answer- inhibition of nucleic
acid synthesis
the mechanism of action of the antimicrobial amphotericin B id -
correct answer- disruption of the cytoplasmic membrane
which of the following statements about drug resistance is
INCORRECT? - correct answer- it is not found in gram-positive
bacteria
drug-resistant populations of microbes arise when - correct
answer- exposure to drugs selectively kills sensitive cells,
allowing overgrowth of resistant cells
a compound is extracted from a microbial culture and is
modified in the laboratory for use as an oral medication. This
product would be a - correct answer- semisynthetic
antimicrobial
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Which group of synthetic antimicrobials act as anti-metabolic
drugs because they are structural analogs of para-
aminobenzoic acid (PABA)? - correct answer- sulfonamides
which group of antimicrobials prevent the formation of a peptide
bond in protein synthesis? - correct answer- chloramphenicol
microbes known as resident microbiota are - correct answer-
microorganisms that remain with the person throughout most of
their life
Biological transmission differs from mechanical transmission in
that biological transmission - correct answer- involves
reproduction of a pathogen in an arthropod vector prior to
transmission
the incidence (new cases) of scarlet fever in the year 2000 in
the United States was 12.43/100,000 cases. This means -
correct answer- there were 12.43 new cases of scarlet fever for
every 100,000 people in the United States in the year 2000
which of then following situations is NOT a way in which a baby
acquires normal microbiota? - correct answer- microbes cross
the placenta during pregnancy
BIO 250 FINAL EXAM QUESTIONS AND
ANSWERS 2025
which of the following is used to sterilize items that should not,
or cannot, be exposed to heat or water? - correct answer-
ethylene oxide
A scientist develops a new medication that is a protein
compound and that must be administered by injection. Which of
the following would be the most effective and safest means of
preparing a sterile solution of the new medication? - correct
answer- filtration
Why are endospores used to measure the effectiveness of
autoclave sterilization? - correct answer- endospores are very
hard to destroy
which of the following is an example of pasteurization? - correct
answer- heat is used to kill potential pathogens in apple juice
which is CORRECT regarding the rate of microbial death? -
correct answer- cells in a culture die at a constant rate?
,2 | Page
which of the following factors will influence the action of
antimicrobial agents? - correct answer- - the number of
microorganisms
-the type of microorganisms present
- temperature and ph
- mode and dosage of the agent
which of the following is NOT a target of drugs that inhibit
protein synthesis? - correct answer- interference with alanine -
alanine bridges in tetrapeptide
an antibiotic is - correct answer- a naturally occurring
compound that kills microbes or inhibits their growth
An antimicrobial that inhibits cell wall synthesis will result in
which of the following? - correct answer- cells become more
susceptible to osmotic pressure
which of the following is NOT an approach to combat drug-
resistant bacteria? - correct answer- flood a patients system
with healthy bacteria to quickly remove access to nutrients and
starve the pathogen
,3 | Page
the mechanism of action of the antibiotic rifampin (used to treat
tuberculosis infections) is - correct answer- inhibition of nucleic
acid synthesis
the mechanism of action of the antimicrobial amphotericin B id -
correct answer- disruption of the cytoplasmic membrane
which of the following statements about drug resistance is
INCORRECT? - correct answer- it is not found in gram-positive
bacteria
drug-resistant populations of microbes arise when - correct
answer- exposure to drugs selectively kills sensitive cells,
allowing overgrowth of resistant cells
a compound is extracted from a microbial culture and is
modified in the laboratory for use as an oral medication. This
product would be a - correct answer- semisynthetic
antimicrobial
, 4 | Page
Which group of synthetic antimicrobials act as anti-metabolic
drugs because they are structural analogs of para-
aminobenzoic acid (PABA)? - correct answer- sulfonamides
which group of antimicrobials prevent the formation of a peptide
bond in protein synthesis? - correct answer- chloramphenicol
microbes known as resident microbiota are - correct answer-
microorganisms that remain with the person throughout most of
their life
Biological transmission differs from mechanical transmission in
that biological transmission - correct answer- involves
reproduction of a pathogen in an arthropod vector prior to
transmission
the incidence (new cases) of scarlet fever in the year 2000 in
the United States was 12.43/100,000 cases. This means -
correct answer- there were 12.43 new cases of scarlet fever for
every 100,000 people in the United States in the year 2000
which of then following situations is NOT a way in which a baby
acquires normal microbiota? - correct answer- microbes cross
the placenta during pregnancy
