PORTAGE LATEST
MICROBIOLOGY
EXAM #3
You want to observe the size and shape of a cell. What is the easiest
staining technique that you could perform? Name at least one dye you
would use during this process - ANSWERS-Simple stain. You could use
any of the following: methylene blue, crystal violet, safranin, or fuschin
You suspect a patient may have TB. Once a sample has been obtained, it
is sent off to the lab for an acid-fast stain. If the patient were infected
with TB, describe what you would expect to see on the stained side -
ANSWERS-You would expect to see red cells (TB+) on a blue
background (TB negative)
True or False: If a patient is suspected of having malaria, a Giemsa stain
would be an appropriate differential test to perform - ANSWERS-True.
Giemsa stains are often used in the clinical setting to aid in the diagnosis
of blood parasites
A micrometer is defined as - ANSWERS-10^-6
A nanometer is defined as - ANSWERS-10^-9
END OF
PAGE 1
, PORTAGE LATEST
MICROBIOLOGY
EXAM #3
True or False: A nanometer is longer than a micrometer - ANSWERS-
False
Resolution (short answer) - ANSWERS-Distance between two objects at
which the objects still can be seen as separate. Poor or low resolution
means two (or more) objects may appear as one
Contrast (short answer) - ANSWERS-Difference in light absorbance
between two objects. Poor contrast gives a high background and makes
the visualization of multiple objects difficult.
Assuming a constant (non-adjustable) light source power, identify the
part of the microscope you would adjust to limit the amount of light
entering the microscope (multiple choice) - ANSWERS-The iris
diaphragm
Assuming a fixed ocular, identify the part of the microscope you would
adjust to enhance the magnification of a sample - ANSWERS-Objective
True or False: Staining is often required to image a cell that is adherent
and flat (thin) - ANSWERS-True
END OF
PAGE 2
MICROBIOLOGY
EXAM #3
You want to observe the size and shape of a cell. What is the easiest
staining technique that you could perform? Name at least one dye you
would use during this process - ANSWERS-Simple stain. You could use
any of the following: methylene blue, crystal violet, safranin, or fuschin
You suspect a patient may have TB. Once a sample has been obtained, it
is sent off to the lab for an acid-fast stain. If the patient were infected
with TB, describe what you would expect to see on the stained side -
ANSWERS-You would expect to see red cells (TB+) on a blue
background (TB negative)
True or False: If a patient is suspected of having malaria, a Giemsa stain
would be an appropriate differential test to perform - ANSWERS-True.
Giemsa stains are often used in the clinical setting to aid in the diagnosis
of blood parasites
A micrometer is defined as - ANSWERS-10^-6
A nanometer is defined as - ANSWERS-10^-9
END OF
PAGE 1
, PORTAGE LATEST
MICROBIOLOGY
EXAM #3
True or False: A nanometer is longer than a micrometer - ANSWERS-
False
Resolution (short answer) - ANSWERS-Distance between two objects at
which the objects still can be seen as separate. Poor or low resolution
means two (or more) objects may appear as one
Contrast (short answer) - ANSWERS-Difference in light absorbance
between two objects. Poor contrast gives a high background and makes
the visualization of multiple objects difficult.
Assuming a constant (non-adjustable) light source power, identify the
part of the microscope you would adjust to limit the amount of light
entering the microscope (multiple choice) - ANSWERS-The iris
diaphragm
Assuming a fixed ocular, identify the part of the microscope you would
adjust to enhance the magnification of a sample - ANSWERS-Objective
True or False: Staining is often required to image a cell that is adherent
and flat (thin) - ANSWERS-True
END OF
PAGE 2
