OBM Test 1 Study Guide Questions and
Answers
Which microscope achieves the highest magnification and greatest resolution?
Select one:
A. darkfield microscope
B. compound light microscope
C. electron microscope
D. fluorescence microscope
E. phase-contrast microscope - ✅✅c
Assume you stain Bacillus by applying malachite green with heat and then
counterstaining with safranin. Through the microscope, the green structures are
Select one:
A. cell walls.
B. endospores.
C. capsules.
D. flagella.
E. The answer cannot be determined. - ✅✅b
A student is looking at a bacterial specimen using the oil immersion lens, but has
forgotten to put immersion oil on the slide. The specimen will appear
Select one:
A. somewhat fuzzy and have poor resolution.
B. the same as it would if the immersion oil was used.
,C. smaller than it would if immersion oil was used.
D. larger than it would if immersion oil was used.
E. to have no color. - ✅✅a
n microscopy, the term resolution
Select one:
A. is the same as the total magnification of a specimen.
B. is improved when longer wavelengths of light are employed.
C. refers to the ability to distinguish fine structure and detail in a specimen.
D. refers to magnification when using the electron microscope.
E. is only observed in stained specimens. - ✅✅c
The purpose of a mordant in the Gram stain is to
Select one:
A. make the bacterial cells larger.
B. prevent the crystal violet from leaving the cells.
C. remove the simple stain.
D. make the flagella visible.
E. make gram-negative cells visible. - ✅✅b
Which of the following statements about biofilms is FALSE?
Select one:
a. Biofilms in pipes can block the flow of water.
, b. Compared to free-living bacteria, biofilms are more sensitive to antibiotics.
c. Biofilms on medical devices cause infections.
d. Biofilms in your body protect mucous membranes from harmful microbes.
e. Biofilms on rocks provide food for animal life. - ✅✅b
The term used to describe a disease-causing microorganism is
Select one:
A. microbe.
B. bacterium.
C. pathogen.
D. virus.
E. infection. - ✅✅c
A prokaryotic cell may possess each of the following cellular components EXCEPT
Select one:
A. ribosomes.
B. a cell wall.
C. a cell membrane.
D. flagella.
E. a nucleus. - ✅✅e
In the name Staphylococcus aureus, aureus is the
Select one:
A. genus.
Answers
Which microscope achieves the highest magnification and greatest resolution?
Select one:
A. darkfield microscope
B. compound light microscope
C. electron microscope
D. fluorescence microscope
E. phase-contrast microscope - ✅✅c
Assume you stain Bacillus by applying malachite green with heat and then
counterstaining with safranin. Through the microscope, the green structures are
Select one:
A. cell walls.
B. endospores.
C. capsules.
D. flagella.
E. The answer cannot be determined. - ✅✅b
A student is looking at a bacterial specimen using the oil immersion lens, but has
forgotten to put immersion oil on the slide. The specimen will appear
Select one:
A. somewhat fuzzy and have poor resolution.
B. the same as it would if the immersion oil was used.
,C. smaller than it would if immersion oil was used.
D. larger than it would if immersion oil was used.
E. to have no color. - ✅✅a
n microscopy, the term resolution
Select one:
A. is the same as the total magnification of a specimen.
B. is improved when longer wavelengths of light are employed.
C. refers to the ability to distinguish fine structure and detail in a specimen.
D. refers to magnification when using the electron microscope.
E. is only observed in stained specimens. - ✅✅c
The purpose of a mordant in the Gram stain is to
Select one:
A. make the bacterial cells larger.
B. prevent the crystal violet from leaving the cells.
C. remove the simple stain.
D. make the flagella visible.
E. make gram-negative cells visible. - ✅✅b
Which of the following statements about biofilms is FALSE?
Select one:
a. Biofilms in pipes can block the flow of water.
, b. Compared to free-living bacteria, biofilms are more sensitive to antibiotics.
c. Biofilms on medical devices cause infections.
d. Biofilms in your body protect mucous membranes from harmful microbes.
e. Biofilms on rocks provide food for animal life. - ✅✅b
The term used to describe a disease-causing microorganism is
Select one:
A. microbe.
B. bacterium.
C. pathogen.
D. virus.
E. infection. - ✅✅c
A prokaryotic cell may possess each of the following cellular components EXCEPT
Select one:
A. ribosomes.
B. a cell wall.
C. a cell membrane.
D. flagella.
E. a nucleus. - ✅✅e
In the name Staphylococcus aureus, aureus is the
Select one:
A. genus.
