STRAIGHTERLINE BIO250 -
MICROBIOLOGY FINAL EXAM STUDY
GUIDE WITH 170 QUESTIONS AND
CORRECT ANSWERS RATED
A+2026/2027
In the nitrogen cycle, which of the following steps involves removal of nitrogen
from the atmosphere by bacteria?
Nitrogen Fixation
If enough H+ ions are added to pure water to raise the H+ concentration of the
solution to ten times higher than the original concentration, what is the resulting
OH- concentration of the solution?
10-8 M
Which of the following is a scientific name?
Streptococcus pyogenes
Eosin-methylene blue agar, or EMB, is a commonly used bacteriological medium
for growing gram-negative bacteria from complex environments. It contains two
dyes, eosin and methylene blue, as well as the sugar lactose. Eosin is a pH
indicator that changes color when the medium is acidic, while methylene blue
inhibits the growth of most gram-positive bacteria. If an organism consumes
lactose, acid will be produced, causing the bacterial colonies to change color.
Based upon this description, this medium is ______
differential and selective
A diagram of the three domains (Bacteria, Archaea, Eukarya) proceeding from the
Last Universal Common Ancestor would show Archaea
branching off the Domain Eukarya.
In the cell cytoplasm, molecules of ATP are a
,Solute
Which of the following parts of a microscope magnifies the specimen to produce
a real image of the specimen?
Objective lens
The two major groups of helminths are ___ and the ___
roundworm; flatworms
All of the following pertain to virus envelopes except
located between the capsid and nucleic acid
A protozoan having flagellum would be classified in the genus
Trypanosoma
Antiviral drugs are often difficult to develop, largely because
viruses are obligate intracellular parasites so the drugs must enter the host cell
and often cause toxic side effects in order to destroy the virus
The activation of a prophage is called...
induction
Endospores are
metabolically inactive, resistant to heat and chemical destruction, resistant to
destruction by radiation, living structures
The endosymbiotic theory has been developed to explain the emergence of...
eukaryotes
A treatment for bacterial infections from the early 20th century has made a
comeback; the use of bacterial viruses to eliminate bacterial infections. Which
explanation most accurately describes the reason for return of this treatment?
A negative RNA virus must first
synthesize a positive RNA copy of its genome
,You've just isolated a new bacterium in pure culture, and you culture it on a
general purpose medium where its cells have a coccobacillus morphology. When
you examine the cells after culturing on a variety of differential media, you fine
that in some cases, the cells appear as coccobacillus, but in others, they can be
filamentous, cocci, or club-shaped. The best explanation for this observation is
that..
the bacterium is pleomorphic
Two functions of bacterial appendages are___ and ___
attachment; motility
A group of protozoa that are not motile are the...
Plasmodium sp.
During the Gram stain, the appplication of alcohol results in the decolorization of
___ cells
Gram-negative
Lysozyme is most effective against
gram positive organisms
The transfer of genes during bacterial conjugation involves rigid, tubular
appendages called ___
sex pili
Which of the following does not pertain to helminths?
Members of the Kingdom Protista
The site for ATP synthesis in bacterial cells is the...
cell membrane
The core of every virus particle always contains...
Either DNA or RNA
Which of the following is not a function of the eukaryotic glycocalyx?
, Movement
Two noncellular agents, smaller than viruses, are the infectious proteins called
_____ and the infectious RNA strands called _____.
Prions; viroids
What is a characteristic of aerobic respiration?
The process includes glycolysis, the Krebs cycle, and the electron transport chain.
In completing protein synthesis in a prokaryote, what basic message is carried by
a specialized codon that has no corresponding tRNA?
"Terminate here."
Microbial drug resistance can be caused by mutations or by introduction of new
genes into a population. Which of the following can only be caused by the
introduction of new genes into a population?
new enzymes that inactivate the drug are synthesized
Why do the hands, feet, and breasts have more lymphatic vessels for host
defense than other areas of the human body?
They have a high risk for infection due to frequent contact.
Penicillin functions as an antimicrobial agent by inhibiting bacterial...
cell wall synthesis.
Which class of eukaryotic microorganisms can be subdivided into groups such as
Mastigophora, Sarcodina, Ciliophora, and Apicomplexa?
Protozoa
Genetic material can be excised from one chromosome and directly integrated
into another via...
transposons
What immune cell secretes numerous cytokines that help to coordinate the
response of other immune cells?
MICROBIOLOGY FINAL EXAM STUDY
GUIDE WITH 170 QUESTIONS AND
CORRECT ANSWERS RATED
A+2026/2027
In the nitrogen cycle, which of the following steps involves removal of nitrogen
from the atmosphere by bacteria?
Nitrogen Fixation
If enough H+ ions are added to pure water to raise the H+ concentration of the
solution to ten times higher than the original concentration, what is the resulting
OH- concentration of the solution?
10-8 M
Which of the following is a scientific name?
Streptococcus pyogenes
Eosin-methylene blue agar, or EMB, is a commonly used bacteriological medium
for growing gram-negative bacteria from complex environments. It contains two
dyes, eosin and methylene blue, as well as the sugar lactose. Eosin is a pH
indicator that changes color when the medium is acidic, while methylene blue
inhibits the growth of most gram-positive bacteria. If an organism consumes
lactose, acid will be produced, causing the bacterial colonies to change color.
Based upon this description, this medium is ______
differential and selective
A diagram of the three domains (Bacteria, Archaea, Eukarya) proceeding from the
Last Universal Common Ancestor would show Archaea
branching off the Domain Eukarya.
In the cell cytoplasm, molecules of ATP are a
,Solute
Which of the following parts of a microscope magnifies the specimen to produce
a real image of the specimen?
Objective lens
The two major groups of helminths are ___ and the ___
roundworm; flatworms
All of the following pertain to virus envelopes except
located between the capsid and nucleic acid
A protozoan having flagellum would be classified in the genus
Trypanosoma
Antiviral drugs are often difficult to develop, largely because
viruses are obligate intracellular parasites so the drugs must enter the host cell
and often cause toxic side effects in order to destroy the virus
The activation of a prophage is called...
induction
Endospores are
metabolically inactive, resistant to heat and chemical destruction, resistant to
destruction by radiation, living structures
The endosymbiotic theory has been developed to explain the emergence of...
eukaryotes
A treatment for bacterial infections from the early 20th century has made a
comeback; the use of bacterial viruses to eliminate bacterial infections. Which
explanation most accurately describes the reason for return of this treatment?
A negative RNA virus must first
synthesize a positive RNA copy of its genome
,You've just isolated a new bacterium in pure culture, and you culture it on a
general purpose medium where its cells have a coccobacillus morphology. When
you examine the cells after culturing on a variety of differential media, you fine
that in some cases, the cells appear as coccobacillus, but in others, they can be
filamentous, cocci, or club-shaped. The best explanation for this observation is
that..
the bacterium is pleomorphic
Two functions of bacterial appendages are___ and ___
attachment; motility
A group of protozoa that are not motile are the...
Plasmodium sp.
During the Gram stain, the appplication of alcohol results in the decolorization of
___ cells
Gram-negative
Lysozyme is most effective against
gram positive organisms
The transfer of genes during bacterial conjugation involves rigid, tubular
appendages called ___
sex pili
Which of the following does not pertain to helminths?
Members of the Kingdom Protista
The site for ATP synthesis in bacterial cells is the...
cell membrane
The core of every virus particle always contains...
Either DNA or RNA
Which of the following is not a function of the eukaryotic glycocalyx?
, Movement
Two noncellular agents, smaller than viruses, are the infectious proteins called
_____ and the infectious RNA strands called _____.
Prions; viroids
What is a characteristic of aerobic respiration?
The process includes glycolysis, the Krebs cycle, and the electron transport chain.
In completing protein synthesis in a prokaryote, what basic message is carried by
a specialized codon that has no corresponding tRNA?
"Terminate here."
Microbial drug resistance can be caused by mutations or by introduction of new
genes into a population. Which of the following can only be caused by the
introduction of new genes into a population?
new enzymes that inactivate the drug are synthesized
Why do the hands, feet, and breasts have more lymphatic vessels for host
defense than other areas of the human body?
They have a high risk for infection due to frequent contact.
Penicillin functions as an antimicrobial agent by inhibiting bacterial...
cell wall synthesis.
Which class of eukaryotic microorganisms can be subdivided into groups such as
Mastigophora, Sarcodina, Ciliophora, and Apicomplexa?
Protozoa
Genetic material can be excised from one chromosome and directly integrated
into another via...
transposons
What immune cell secretes numerous cytokines that help to coordinate the
response of other immune cells?
