MICROBIOLOGY STRAIGHTERLINE (QUIZZES) AND
ANSWERS
________ molecules deliver amino acids to ribosomes during translation.
a. Messenger RNA (mRNA)
b. Transfer RNA (tRNA)
c. Ribosomal RNA (rRNA)
d. Heterogeneous nuclear RNA (hnRNA) - answer-b. Transfer RNA (tRNA)
__________ alter repressor proteins thereby increasing the rate of transcription initiation.
a. Inducers
b. Corepressors
c. Effectors
d. Modulators - answer-a. Inducers
__________ is a measure of the randomness or disorder of a system.
a. Entropy
b. Enthalpy
c. Free energy
d. Synergy - answer-a. Entropy
______________ is used to control transcription of some anabolic pathways involved in amino acid
biosynthesis.
a. Attenuation
b. Catabolite repression
c. Induction
d. All of the choices are correct. - answer-a. Attenuation
__________________ are hollow tube-like structures that hold some archaeal daughter cells
together after cell division while____________ are grappling hook-like structures that appear to
attach archaeal cells to surfaces.
a. Pili; hami
b. Cannulae; hami
c. Hami; fimbriae
d. Cannulae; pili - answer-b. Cannulae; hami
0.2 mls of a 10^-4 dilution of a virus preparation yields 90 plaques. What is the number of PFU per
ml in the undiluted virus preparation?
a. 9.0 × 10^5
b. 4.5 × 10^6
c. 4.5 × 10^7
d. 9.0 × 10^8 - answer-b. 4.5 × 10^6
,A basidium...
a. is found within basidiocarp (fruiting body).
b. is produced at the tip of hyphae.
c. is club-shaped.
d. All of the choices are correct. - answer-d. All of the choices are correct.
A culture system with constant environmental conditions maintained through continual provision of
nutrient and removal of wastes is called __________ culture system.
a. continuous
b. batch
c. fed-batch
d. semicontinuous - answer-a. continuous
A general term used to describe groups based on mutual similarity or evolutionary relatedness is
______.
a. class
b. taxa
c. system
d. group - answer-b. taxa
A graduate student is researching the spread of mosquito vectors and dengue fever into the
southern United States. She has collected a substantial amount of data regarding the locations
where the vector has been detected as well as the incidence of the dengue fever virus in both the
vector population and in humans. What application would enable her to effectively illustrate
patterns of vector and disease spread?
a. Geographic Information Systems
b. Remote sensing
c. DNA microarrays
d. DNA fingerprinting - answer-a. Geographic Information Systems
A major fungal genus that produces aflatoxin is
a. Rhizopus.
b. Aspergillus.
c. Claviceps.
d. Penicillium. - answer-b. Aspergillus.
A mast cell is similar to a basophil in that both...
a. are types of white blood cells.
b. are agranulocytic.
c. release vasoactive mediators.
d. act as primary phagocytes.
e. None of the choices are correct - answer-c. release vasoactive mediators.
,A microbiologist would like to use a noncompetent genus of streptococcal bacteria, Enterococcus
faecalis, as a cloning host to express genes from Streptococcus pneumoniae, which is naturally
competent. Is this possible?
a. Yes; electroporation or chemical transformation can be used to make Enterococcus competent,
and then genes from Streptococcus can be introduced via a cloning vector.
b. Yes; electroporation or chemical transformation can be used to make non-competent
Streptococcus mutants, from which genes can be inserted into a cloning vector and introduced into
Enterococcus.
c. No; competence factor is an essential protein that enables the uptake of foreign DNA, therefore a
cloning host such as Enterococcus that lacks competence factor protein is unable to be transformed
by electroporation or chemical transformation.
d. Yes; since the cloning host and the DNA to be introduced are both from bacteria that are stre -
answer-a. Yes; electroporation or chemical transformation can be used to make Enterococcus
competent, and then genes from Streptococcus can be introduced via a cloning vector.
A newly described bacterial species has been shown to use CO2 as its carbon source. Its energy
source and its source of reducing power (electrons) are inorganic chemicals. Which term would best
describe this nutritional type?
a. Chemolithoheterotroph
b. Photoorganoheterotroph
c. Photolithoheterotroph
d. Chemolithoatotroph - answer-d. Chemolithoatotroph
A public health microbiologist plans to screen a particular bacterial species that was isolated from
several patients in an intensive care unit to detect if any of the cells are penicillin-resistant mutants.
What is the first step in conducting this experiment?
a. Determine whether or not wild type cells of the same bacterial species are susceptible to
penicillin.
b. Test the cells to see if they can grow on media to which penicillin has been added.
c. Perform an antibiotic susceptibility test on the cells using antibiotics other than penicillin that are
known to be effective.
d. Set up an Ames test to see if any of the isolates are mutagenic. - answer-a. Determine whether or
not wild type cells of the same bacterial species are susceptible to penicillin.
A purine or pyrimidine that is attached to a sugar, either ribose or deoxyribose, which is attached to
one or more phosphate groups is called a _______.
a. nucleotide
b. nucleoside
c. nitrogenous base
d. nucleic acid - answer-a. nucleotide
A reaction that releases energy is __________.
a. exergonic
b. endergonic
c. impossible
d. None of the choices are correct. - answer-a. exergonic
, A scientist wishes to develop an antimicrobial agent that specifically targets replication elongation in
Escherichia coli without interfering with proteins that catalyze other replication processes. Which of
the following experimental designs is most appropriate for the scientist to explore?
a. Develop a molecule that interferes with the DNA-binding ability of DNA polymerase III core
enzyme.
b. Modify an existing antibiotic to act as a competitive inhibitor of DNA polymerase I.
c. Design a drug that modifies the structural configuration of DNA at the oriC locus.
d. Create a novel protein that acts as a competitive inhibitor of the DNA ligase binding site. - answer-
a. Develop a molecule that interferes with the DNA-binding ability of DNA polymerase III core
enzyme.
A wide variety of microorganisms are commercially used to manufacture _________ for human
consumption.
a. vitamins
b. sugars
c. fatty acids
d. none of the choices - answer-a. vitamins
Acid-fast organisms such as Mycobacterium tuberculosis contain lipids constructed from
________________in their cell walls.
a. proteins
b. carbohydrates
c. mycolic acids
d. peptidoglycan - answer-c. mycolic acids
All of the following are common habitats or hosts of chytrids EXCEPT _________.
a. freshwater
b. mud
c. soil
d. the human intestine
e. insects - answer-d. the human intestine
All of the following are included in the Basidiomycetes EXCEPT _________.
a. stolons
b. puffballs
c. yeasts
d. smuts - answer-a. stolons
All of the following are reasons why some scientists believe that the term "prokaryote" is a
somewhat artificial designation and should be discarded EXCEPT...
a. Some bacteria have internal membranous structures.
b. Some bacteria have their genetic material enclosed within a membrane.
c. Some bacteria have 80S ribosomes.
d. Many bacterial have cytoskeletal elements. - answer-c. Some bacteria have 80S ribosomes.
ANSWERS
________ molecules deliver amino acids to ribosomes during translation.
a. Messenger RNA (mRNA)
b. Transfer RNA (tRNA)
c. Ribosomal RNA (rRNA)
d. Heterogeneous nuclear RNA (hnRNA) - answer-b. Transfer RNA (tRNA)
__________ alter repressor proteins thereby increasing the rate of transcription initiation.
a. Inducers
b. Corepressors
c. Effectors
d. Modulators - answer-a. Inducers
__________ is a measure of the randomness or disorder of a system.
a. Entropy
b. Enthalpy
c. Free energy
d. Synergy - answer-a. Entropy
______________ is used to control transcription of some anabolic pathways involved in amino acid
biosynthesis.
a. Attenuation
b. Catabolite repression
c. Induction
d. All of the choices are correct. - answer-a. Attenuation
__________________ are hollow tube-like structures that hold some archaeal daughter cells
together after cell division while____________ are grappling hook-like structures that appear to
attach archaeal cells to surfaces.
a. Pili; hami
b. Cannulae; hami
c. Hami; fimbriae
d. Cannulae; pili - answer-b. Cannulae; hami
0.2 mls of a 10^-4 dilution of a virus preparation yields 90 plaques. What is the number of PFU per
ml in the undiluted virus preparation?
a. 9.0 × 10^5
b. 4.5 × 10^6
c. 4.5 × 10^7
d. 9.0 × 10^8 - answer-b. 4.5 × 10^6
,A basidium...
a. is found within basidiocarp (fruiting body).
b. is produced at the tip of hyphae.
c. is club-shaped.
d. All of the choices are correct. - answer-d. All of the choices are correct.
A culture system with constant environmental conditions maintained through continual provision of
nutrient and removal of wastes is called __________ culture system.
a. continuous
b. batch
c. fed-batch
d. semicontinuous - answer-a. continuous
A general term used to describe groups based on mutual similarity or evolutionary relatedness is
______.
a. class
b. taxa
c. system
d. group - answer-b. taxa
A graduate student is researching the spread of mosquito vectors and dengue fever into the
southern United States. She has collected a substantial amount of data regarding the locations
where the vector has been detected as well as the incidence of the dengue fever virus in both the
vector population and in humans. What application would enable her to effectively illustrate
patterns of vector and disease spread?
a. Geographic Information Systems
b. Remote sensing
c. DNA microarrays
d. DNA fingerprinting - answer-a. Geographic Information Systems
A major fungal genus that produces aflatoxin is
a. Rhizopus.
b. Aspergillus.
c. Claviceps.
d. Penicillium. - answer-b. Aspergillus.
A mast cell is similar to a basophil in that both...
a. are types of white blood cells.
b. are agranulocytic.
c. release vasoactive mediators.
d. act as primary phagocytes.
e. None of the choices are correct - answer-c. release vasoactive mediators.
,A microbiologist would like to use a noncompetent genus of streptococcal bacteria, Enterococcus
faecalis, as a cloning host to express genes from Streptococcus pneumoniae, which is naturally
competent. Is this possible?
a. Yes; electroporation or chemical transformation can be used to make Enterococcus competent,
and then genes from Streptococcus can be introduced via a cloning vector.
b. Yes; electroporation or chemical transformation can be used to make non-competent
Streptococcus mutants, from which genes can be inserted into a cloning vector and introduced into
Enterococcus.
c. No; competence factor is an essential protein that enables the uptake of foreign DNA, therefore a
cloning host such as Enterococcus that lacks competence factor protein is unable to be transformed
by electroporation or chemical transformation.
d. Yes; since the cloning host and the DNA to be introduced are both from bacteria that are stre -
answer-a. Yes; electroporation or chemical transformation can be used to make Enterococcus
competent, and then genes from Streptococcus can be introduced via a cloning vector.
A newly described bacterial species has been shown to use CO2 as its carbon source. Its energy
source and its source of reducing power (electrons) are inorganic chemicals. Which term would best
describe this nutritional type?
a. Chemolithoheterotroph
b. Photoorganoheterotroph
c. Photolithoheterotroph
d. Chemolithoatotroph - answer-d. Chemolithoatotroph
A public health microbiologist plans to screen a particular bacterial species that was isolated from
several patients in an intensive care unit to detect if any of the cells are penicillin-resistant mutants.
What is the first step in conducting this experiment?
a. Determine whether or not wild type cells of the same bacterial species are susceptible to
penicillin.
b. Test the cells to see if they can grow on media to which penicillin has been added.
c. Perform an antibiotic susceptibility test on the cells using antibiotics other than penicillin that are
known to be effective.
d. Set up an Ames test to see if any of the isolates are mutagenic. - answer-a. Determine whether or
not wild type cells of the same bacterial species are susceptible to penicillin.
A purine or pyrimidine that is attached to a sugar, either ribose or deoxyribose, which is attached to
one or more phosphate groups is called a _______.
a. nucleotide
b. nucleoside
c. nitrogenous base
d. nucleic acid - answer-a. nucleotide
A reaction that releases energy is __________.
a. exergonic
b. endergonic
c. impossible
d. None of the choices are correct. - answer-a. exergonic
, A scientist wishes to develop an antimicrobial agent that specifically targets replication elongation in
Escherichia coli without interfering with proteins that catalyze other replication processes. Which of
the following experimental designs is most appropriate for the scientist to explore?
a. Develop a molecule that interferes with the DNA-binding ability of DNA polymerase III core
enzyme.
b. Modify an existing antibiotic to act as a competitive inhibitor of DNA polymerase I.
c. Design a drug that modifies the structural configuration of DNA at the oriC locus.
d. Create a novel protein that acts as a competitive inhibitor of the DNA ligase binding site. - answer-
a. Develop a molecule that interferes with the DNA-binding ability of DNA polymerase III core
enzyme.
A wide variety of microorganisms are commercially used to manufacture _________ for human
consumption.
a. vitamins
b. sugars
c. fatty acids
d. none of the choices - answer-a. vitamins
Acid-fast organisms such as Mycobacterium tuberculosis contain lipids constructed from
________________in their cell walls.
a. proteins
b. carbohydrates
c. mycolic acids
d. peptidoglycan - answer-c. mycolic acids
All of the following are common habitats or hosts of chytrids EXCEPT _________.
a. freshwater
b. mud
c. soil
d. the human intestine
e. insects - answer-d. the human intestine
All of the following are included in the Basidiomycetes EXCEPT _________.
a. stolons
b. puffballs
c. yeasts
d. smuts - answer-a. stolons
All of the following are reasons why some scientists believe that the term "prokaryote" is a
somewhat artificial designation and should be discarded EXCEPT...
a. Some bacteria have internal membranous structures.
b. Some bacteria have their genetic material enclosed within a membrane.
c. Some bacteria have 80S ribosomes.
d. Many bacterial have cytoskeletal elements. - answer-c. Some bacteria have 80S ribosomes.
