5 THE MICROSCOPE

Question 1

The magnification of 40× matches the:
a. Oil-immersion objective
b. High-power objective
c. Low-power objective
d. Scanning objective

Answer 1

b. High-power objective

Question 2

The magnification of 10× matches the:
a. Oil-immersion objective
b. High-power objective
c. Low-power objective
d. Scanning objective

Answer 2

c. Low-power objective

Question 3

The magnification of 100× matches the:
a. Oil-immersion objective
b. High-power objective
c. Low-power objective
d. Scanning objective

Answer 3

a. Oil-immersion objective

Question 4

The common numerical aperture for the oil-immersion objective is:
a. 0.25NA
b. 0.65NA
c. 1.25NA
d. 1.80NA

Answer 4

c. 1.25NA

Question 5

The common numerical aperture for the high-power objective is:
a. 0.25NA
b. 0.65NA
c. 1.2NA
d. 1.80NA

Answer 5

b. 0.65NA

Question 6

The common numerical aperture for the low-power objective is:
a. 0.25NA
b. 0.65NA
c. 1.2NA
d. 1.8NA

Answer 6

a. 0.25NA

Question 7

The ocular of the microscope can also be called the:
a. Iris field diaphragm
b. Eyepiece
c. Objectives
d. Condenser

Answer 7

b. Eyepiece

Question 8

How should the condenser be positioned assuming that the NA of the condenser is 0.85 with the oil-immersion objective?
a. Highest position possible or very slightly decreased (lowered)
b. Highest (uppermost) position possible
c. Decrease to 1 or 2mm below the slide (lowering condenser slightly)
d. Lowest possible position

Answer 8

b. Highest (uppermost) position possible

Question 9

How should the condenser be positioned assuming that the NA of the condenser is 0.85 with the low-power objective?
a. Highest position possible or very slightly decreased (lowered)
b. Highest (uppermost) position possible
c. Decrease to 1 or 2mm below the slide (lowering condenser slightly)
d. Lowest possible position

Answer 9

c. Decrease to 1 or 2mm below the slide (lowering condenser slightly)

Question 10

Cleaning the objective lens should be done with:
a. Camel’s hair brush
b. Tissue paper
c. Facial tissue
d. Lens paper

Answer 10

d. Lens paper

Question 11

If you are unable to focus the microscope to achieve a sharp view of a specimen, the correct sequence of steps to
be taken is:
a. Replace the objective with one from another microscope, clean the oculars, clean the stage, and clean the objectives.
b. Clean the oculars, clean the stage, clean the objectives, and replace the objective with one from another microscope.
c. Clean the objectives, clean the oculars, and replace the objectives with a new set of objectives.
d. Clean the objectives, replace the objective with one from another microscope, clean the ocular, and clean the stage

Answer 11

c. Clean the objectives, clean the oculars, and replace the objectives with a new set of objectives.

Question 12

What objective must you always use when you first start looking at a slide?
a. High power
b. 100×
c. 40×
d. 10×

Answer 12

d. 10×

Question 13

Which focusing adjustment do you use first when you begin looking at a slide?
a. Small focusing knob
b. Coarse focus
c. Fine focus
d. 4× objective

Answer 13

b. Coarse focus

Question 14

Which objective allows you to see the largest area of the object you are viewing?
a. 4×
b. 10×
c. 100×
d. 40×

Answer 14

a. 4×

Question 15

Describe how to decrease light intensity.
a. Lower the condenser.
b. Close the aperture iris diaphragm.
c. Adjust the dimmer switch.
d. All the above are possible ways to decrease light intensity.

Answer 15

d. All the above are possible ways to decrease light intensity.

Question 16

What do you adjust if you can see through one ocular and not the other?
a. The fine focus
b. The coarse focus
c. Change to a different objective
d. The other ocular

Answer 16

d. The other ocular

Question 17

What do you adjust if you can see two overlapping circles, with part of the object in each circle?
a. The focus
b. The iris diaphragm
c. The width of the oculars
d. Change to a different objective

Answer 17

c. The width of the oculars

Question 18

How do you increase depth of field?
a. Close the aperture of the iris diaphragm.
b. Open the aperture of the iris diaphragm.
c. Use fine focusing.
d. Both a and c.

Answer 18

d. Both a and c.

Question 19

Which focusing knob do you use with the 10× and 40× objectives?
a. Fine focusing knob
b. Coarse and fine focusing knobs, respectively
c. Both fine focusing knob and the iris diaphragm
d. Coarse focusing knob

Answer 19

d. Coarse focusing knob

Question 20

How much are you magnifying something when you are using 10× oculars and the 40× objectives?
a. 40×
b. 400×
c. 4000×
d. Cannot calculate without additional information

Answer 20

b. 400×

Question 21

An adaptation of the brightfield microscope is the:
a. Polarizing microscope
b. Electron microscope
c. Fluorescent microscope
d. Darkfield microscope

Answer 21

a. Polarizing microscope

Question 22

A scanning electron microscope focuses on the surface of the specimen and produces a:
a. One-dimensional image
b. Two-dimensional image
c. Three-dimensional image
d. Four-dimensional image

Answer 22

c. Three-dimensional image

Question 23

A critical design characteristic of the microscope’s objective set is:
a. Wavelength of light used to illuminate the specimen
b. Angular aperture of the light cone captured by the objective
c. Refractive index in the object space between the objective front lens and the specimen
d. All the above are critical design characteristics

Answer 23

d. All the above are critical design characteristics

Question 24

When changing objectives by rotating the nosepiece requires only minimal use of the fine-adjustment knob to
reestablish sharp focus, the set of objectives is described as being:
a. Parfocal
b. Achromatic
c. Planachromatic
d. Either b or c

Answer 24

a. Parfocal

Question 25

Which of the following describes a characteristic representative of digital microscopy?
a. Digital microscopy is driven by an artificial neural network that simulates the way the human brain processes information.
b. Digital microscopy allows for preclassifying leukocytes and erythrocytes.
c. Digital microscopy produces platelet estimates.
d. All the above are representative characteristics of digital microscopy.

Answer 25

d. All the above are representative characteristics of digital microscopy.

Question 26

You are reviewing a hematology slide under the low-power (10×) objective. Which step should be completed
first in order to scan the slide?
a. Use the coarse focus adjustment, followed by the fine focus adjustment.
b. Use the fine focus adjustment, followed by the coarse focus adjustment.
c. Add oil to the slide.
d. Adjust the light intensity until the background light is
bright but comfortable to view

Answer 26

a. Use the coarse focus adjustment, followed by the fine focus adjustment.

Question 27

You are reviewing a hematology slide under the 100× oil-immersion objective, but the specimen is not in focus. What should you do to resolve the issue?
a. Use the coarse focus adjustment, followed by the fine focus adjustment.
b. Use the fine focus adjustment, followed by the coarse focus adjustment.
c. Add oil to the slide.
d. Adjust the light intensity until the background light is
bright but comfortable to view

Answer 27

c. Add oil to the slide.

Question 28

You have completed a review of a hematology slide using the 100× oil-immersion objective. What should you do
before leaving the workstation?
a. Turn off the light and put the slide away.
b. Wipe the oil from the objective using a tissue, turn off the light, and put the slide away.
c. Remove the oil from the objective with lens paper, turn off the light, and put the slide away.
d. Wipe the oil from the objective with a clean, dry piece of gauze (or Kimwipe).

Answer 28

c. Remove the oil from the objective with lens paper, turn off the light, and put the slide away.