Microbiology Exam 1 Practice Test
MICROBIOLOGY EXAM 1 PRACTICE TEST WITH 170 QUESTIONS
AND CORRECT ANSWERS/ MICROBIOLOGY EXAM 1 PREP TEST
LATEST CHAMBERLAIN
In many cases of disease, the causative agent can be linked to one bacterial
pathogen. However, when you are collecting a specimen from a patient, it is
difficult to obtain just one species of bacterium. Because of this difficulty, good
methods for bacterial isolation are needed to obtain a pure culture (a single,
genetically homogeneous strain of a single species). Why is a pure culture
necessary for the diagnostic process?
A. mixed culture will not grow under lab conditions.
B. a pure culture is required for vaccine production.
C. biochemical tests may be confounded when working with a mixed culture.
D. a pure culture is useful in inoculating other patients. - Correct Answer-C
You want to use a microscope to look at the microbe Giardia lamblia. Specifically,
you would like to see critical detail of internal structures. Which type of
microscope would be best to use?
A. a phase-contrast microscope
B. a light microscope
C. a scanning electron microscope
D. a transmission electron microscope - Correct Answer-D
Which of the following is a potential problem with satisfying Koch's third postulate
in practice?
A. Some disease-causing microorganisms may be found in healthy individuals.
1|Page
, Microbiology Exam 1 Practice Test
B. Some disease-causing microorganisms only cause infection in humans, so no
animal models are available.
C. Not all disease-causing microorganisms can be isolated and grown in pure
culture in the laboratory.
D. Some disease-causing microorganisms will not cause disease in all individuals. -
Correct Answer-B
The bacterial cell wall is composed of ________.
A. cellulose
B. chitin
C. peptidoglycan
D. phospholipids - Correct Answer-C
Which of the following would be a symptom?
A. white blood cell count
B. runny nose
C. headache
D. rash - Correct Answer-C
The curve in Pasteur's swan necked flask was important because ____.
A. it prevented flies from escaping the flask.
B. t allowed only warm air to reach the infusion.
C. It trapped microbes that otherwise would have entered the flask.
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, Microbiology Exam 1 Practice Test
D. It prevented oxygen from reaching organisms inside the flask. - Correct Answer-
C
The Gram stain is useful for distinguishing among which types of microbes?
A. algae
B. bacteria
C. fungi
D. protozoa
E. all of the above - Correct Answer-B
Select the most correct statement about the Gram stain:
A. Iodine acts as the decolorizer in the Gram stain.
B. Gram-positive cells retain the crystal violet dye and the gram-negative cells lose
the dye following the decolorizer step.
C. To obtain the best Gram stain reaction, your cultures should be at least 48
hours old.
D. All of the above are correct. - Correct Answer-B
The peptidoglycan layer of the cell wall:
A. consists of lipopolysaccharides
B. represents a lipid bilayer
C. lacks teichoic acids
D. is only present in gram-positive organisms.
E. none of the above are true - Correct Answer-E
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, Microbiology Exam 1 Practice Test
The counterstain in the gram reaction is:
A. Carbolfuchsin
B. Malachite green
C. Safranin
D. Crystal violet - Correct Answer-C
The first use of aseptic technique to attempt to control the spread of infection can
be traced to:
A. Lister
B. Jenner
C. Koch
D. Fleming - Correct Answer-A
Nosocomial infections are:
A. acquired by mosquito, flea, tick
B. Must be reported to the public
C. Are acquired in the hospital
D. Are often most acquired in day cares - Correct Answer-C
A bacterial population grows most rapidly during ________ phase.
A. stationary
B. Lag
4|Page
MICROBIOLOGY EXAM 1 PRACTICE TEST WITH 170 QUESTIONS
AND CORRECT ANSWERS/ MICROBIOLOGY EXAM 1 PREP TEST
LATEST CHAMBERLAIN
In many cases of disease, the causative agent can be linked to one bacterial
pathogen. However, when you are collecting a specimen from a patient, it is
difficult to obtain just one species of bacterium. Because of this difficulty, good
methods for bacterial isolation are needed to obtain a pure culture (a single,
genetically homogeneous strain of a single species). Why is a pure culture
necessary for the diagnostic process?
A. mixed culture will not grow under lab conditions.
B. a pure culture is required for vaccine production.
C. biochemical tests may be confounded when working with a mixed culture.
D. a pure culture is useful in inoculating other patients. - Correct Answer-C
You want to use a microscope to look at the microbe Giardia lamblia. Specifically,
you would like to see critical detail of internal structures. Which type of
microscope would be best to use?
A. a phase-contrast microscope
B. a light microscope
C. a scanning electron microscope
D. a transmission electron microscope - Correct Answer-D
Which of the following is a potential problem with satisfying Koch's third postulate
in practice?
A. Some disease-causing microorganisms may be found in healthy individuals.
1|Page
, Microbiology Exam 1 Practice Test
B. Some disease-causing microorganisms only cause infection in humans, so no
animal models are available.
C. Not all disease-causing microorganisms can be isolated and grown in pure
culture in the laboratory.
D. Some disease-causing microorganisms will not cause disease in all individuals. -
Correct Answer-B
The bacterial cell wall is composed of ________.
A. cellulose
B. chitin
C. peptidoglycan
D. phospholipids - Correct Answer-C
Which of the following would be a symptom?
A. white blood cell count
B. runny nose
C. headache
D. rash - Correct Answer-C
The curve in Pasteur's swan necked flask was important because ____.
A. it prevented flies from escaping the flask.
B. t allowed only warm air to reach the infusion.
C. It trapped microbes that otherwise would have entered the flask.
2|Page
, Microbiology Exam 1 Practice Test
D. It prevented oxygen from reaching organisms inside the flask. - Correct Answer-
C
The Gram stain is useful for distinguishing among which types of microbes?
A. algae
B. bacteria
C. fungi
D. protozoa
E. all of the above - Correct Answer-B
Select the most correct statement about the Gram stain:
A. Iodine acts as the decolorizer in the Gram stain.
B. Gram-positive cells retain the crystal violet dye and the gram-negative cells lose
the dye following the decolorizer step.
C. To obtain the best Gram stain reaction, your cultures should be at least 48
hours old.
D. All of the above are correct. - Correct Answer-B
The peptidoglycan layer of the cell wall:
A. consists of lipopolysaccharides
B. represents a lipid bilayer
C. lacks teichoic acids
D. is only present in gram-positive organisms.
E. none of the above are true - Correct Answer-E
3|Page
, Microbiology Exam 1 Practice Test
The counterstain in the gram reaction is:
A. Carbolfuchsin
B. Malachite green
C. Safranin
D. Crystal violet - Correct Answer-C
The first use of aseptic technique to attempt to control the spread of infection can
be traced to:
A. Lister
B. Jenner
C. Koch
D. Fleming - Correct Answer-A
Nosocomial infections are:
A. acquired by mosquito, flea, tick
B. Must be reported to the public
C. Are acquired in the hospital
D. Are often most acquired in day cares - Correct Answer-C
A bacterial population grows most rapidly during ________ phase.
A. stationary
B. Lag
4|Page
