Microbiology Test Bank Study Questions
and Answers (2025 Graded A+)
Penicillin controls bacterial growth by:
A) preventing synthesis of the lipopolysaccharide layer
B) inhibiting protein synthesis
C) preventing cross-link formation in peptidoglycan
D) preventing generation of the proton motive force - Correct Ans-preventing cross-link
formation in peptidoglycan
Reproduction via binary fission leads to what type of growth under optimal conditions:
A) linear
B) mixed
C) exponential
D) uptake-limited - Correct Ans-exponential
Protection against osmotic lyses is provided by:
A) lysosomes
B) the cellular plasma membrane
C) the cell's capsule
D) the cell wall - Correct Ans-the cell wall
Name associated with the presense of a cell wall and a capsule together in a bacterial
cell wall:
A) the envelope
B) the capsule
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C) the cytoplasmic membrane D) the cell wall - Correct Ans-the envelope
Which of the following is true about the lag phase:
A) cells adapt to a new medium B) in some cases it may be very short
C) cells replenish spent materials
D) all of the above - Correct Ans-all of the above
A student is asked by the professor to sub-culture a bacterial organism onto fresh media
for future studies. However during sub-culturing the students lock the test tube
preventing oxygen flow into the media. After days the culture dyes. What type of culture
did the student have at hand:
A) obligate aerobe
B) strict anaerobe
C) facultative anaerobe
D) none of the above - Correct Ans-obligate aerobe
Staining procedure designed for bacterial families with high lipid content and resistant to
standard staining:
A) gram stain
B) negative staining
C) acid fast staining
D) simple stain - Correct Ans-acid fast staining
Which of the following is not considered a starvation response?
A) endospore formation
B) synthesis of starvation proteins
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C) cell death at a logrtihmic rate D) a decrease in cellular size and nucleoid condensation
- Correct Ans-cell death at a logrtihmic rate
Organelle responsible for the synthesis of protein in a eukaryotic cell:
A) the smooth ER
B) the rough ER
C) the Golgi complex
D) the nucleus - Correct Ans-the rough ER
Which of the following is the most important structure related to microbial attachment
to cells? A) flagellum
B) plasmid
C) peptidoglycan
D) glycocalix - Correct Ans-glycocalix
Which of the following statement(s) is/are correct when comparing prokaryotic and
eukaryotic genome?
A) bacteria mostly have one circular DNA molecule
B) Eukaryotes have linear DNA C) Both A and B
D) None of the above - Correct Ans-Both A and B
___________ membranes allow some molecules to pass but not all.
A) Permeable
B) Inverted Membrane
C) Selectively Membrane
D) Impermeable - Correct Ans-Selectively Membrane
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The ribosome binding site
A) forms a stem-loop structure in the RNA
B) is located upstream of the promoter sequence
C) is located immediately upstream of the start codon
D) is more likely to be associated with an operon than with a gene encoding a single
protein - Correct Ans-is located immediately upstream of the start codon
The nucleus of a eukaryote does not contain
A) nuclear membrane
B) nucleoid
C) nuclear pores
D) nucleolus - Correct Ans-nucleoid
The protein coat and lipid envelopes are components that help to protect the viral
A) capsid
B) genome
C) tegument
D) spikes - Correct Ans-genome
Which of the following helps protect bacteria from lysis in dilute solution and helps to
determine cellular morphology?
A) plasma membrane
B) capsule
C) gas vacuoles
D) cell wall - Correct Ans-cell wall
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