Question 1

Where should the condenser be located when using the *100 oil objective?&#10;A)lowest position&#10;B)highest position&#10;C)middle position&#10;D)variable depending on amount of light desired

Accepted Answer

The position of the condenser is set to maximize the amount of light coming through the object;its ideal position is set when adjusting for Koehler illumination,and its ideal position is in the highest position.It should not be changed to regulate light intensity.

Question 2

What is the most likely reason for cells on a hemocytometer appearing &#34;fuzzy&#34; when switching from low power to the *40 objective?&#10;A)condenser not lowered enough&#10;B)hemocytometer not cleaned properly&#10;C)oil on the 40* lens&#10;D)cells not allowed to settle

Accepted Answer

Oil should never be allowed to touch any lens that is not an oil immersion lens.If it mistakenly does get on the 40* lens,the object will appear fuzzy and unclear.The condenser should be in the highest position for best visualization.If a hemocytometer is dirty,it will be difficult to distinguish cells from debris.If cells are not allowed to settle,they will not all be in the same plane of focus and some may be missed for counting purposes.

Question 3

An object is brought into focus using the 10* objective lens.When the 40* objective lens is moved into position,only a minor adjustment using the fine focus adjustment is required to bring it clearly into focus.What is the term used to describe lenses with this feature?

A)parcentric
B)achromatic
C)plan-achromatic
D)parfocal

parfocal

Accepted Answer

When objective lenses are parfocal,only a minor adjustment using the fine focus knob is required to bring an object into focus when moving from one lens to another.Achromatic and plan-achromatic describe how (or if)a lens corrects for the curvature in a field,thus whether or not only part of or an entire field is in focus at the same time.Parcentric means that an image in the center of a field remains close to the center when a different objective lens is brought into position.

Question 4

What solution is best for cleaning lenses?&#10;A)commercial glass-cleaning solution (e.g., Windex)&#10;B)water&#10;C)benzene&#10;D)xylol

Accepted Answer

A commercial glass cleaning solution is best used for cleaning lenses.Water will often only smudge anything present,especially on an oil immersion lens.Benzene and xylol are solvents that are carcinogenic and should not be used.

Question 5

Which of the following would be least likely to cause a &#34;fuzzy&#34; image on oil power?&#10;A)using a plan-achromatic objective lens&#10;B)objective not screwed in tightly&#10;C)not enough oil on the slide when using oil immersion lens&#10;D)focus controls not adjusted

Accepted Answer

Using a plan-achromatic lens gives a flat field so that the edges of the field are in focus at the same time as the center.When an objective is not screwed in tightly,not enough oil has been used on a slide when using an oil immersion lens,or the focus controls are not adjusted,an image is likely to be fuzzy or unclear,making it difficult to visualize objects.

Question 6

The ability to distinguish between two objects that are situated close to one another as separate entities is&#10;A)resolution.&#10;B)parfocal.&#10;C)contrast.&#10;D)parcentric.

Accepted Answer

Resolution is the ability to distinguish between two objects that are close together as two distinct entities.Contrast makes an image sharper (i.e.,clearer),but does not affect resolution.If lenses are parfocal,moving from one objective to another will require only minor adjustments in the fine focus.If they are parcentric,an object in the center of one field using one lens will be close to the center when another objective is moved into position.

Question 7

How should a microscope be carried?&#10;A)both hands supporting the base&#10;B)both hands around the arm&#10;C)one hand around the arm and the other holding the oculars in place&#10;D)one hand under the base and the other around the arm

Accepted Answer

For best support when carrying a microscope,one hand should be placed under the base and the other around the arm.This makes dropping and damaging the microscope less likely.

Question 8

Why is it not advisable to interchange one ocular lens with another from a different brand microscope?&#10;A)The two ocular lenses in a microscope are optically matched with one another.&#10;B)The fitting for the ocular lenses varies, so they will not fit in another microscope.&#10;C)They cannot be removed from the microscope.&#10;D)They are fragile and are likely to break when removed from the microscope.

Accepted Answer

Ocular lenses are optically matched to one another and so should not be interchanged with one another,especially not one of another brand.They can and are,though,easily removed for such tasks as cleaning.

Question 9

The device used to assist in finding a cell of interest at a later time is called a&#10;A)microlocator.&#10;B)micrometer.&#10;C)reticle.&#10;D)hemocytometer.

Accepted Answer

The microlocator slide,when used as directed,permits a specific cell or finding on a slide to be found at a later time by referring to the recorded letter-number combination for the object of interest.

Question 10

What immersion oil is used most commonly in hematology?&#10;A)type A&#10;B)type B&#10;C)type C&#10;D)type D

Accepted Answer

The different types of oil differ with respect to their viscosity (i.e.,thickness).The one most commonly used in hematology is type B,which has high viscosity.Type A has a low viscosity,and type C has a very high viscosity.

Question 11

What should be adjusted if two overlapping images,instead of only one,are seen when looking through a microscope?&#10;A)field diaphragm&#10;B)fine adjustment knob&#10;C)condenser knob&#10;D)interpupillary control

Accepted Answer

The answer of What should be adjusted if two overlapping...

Question 12

An image viewed under the microscope is clearly seen under both the 10* and 40* objectives,but it is not visible under *100.What is the most likely reason for this?&#10;A)Oil is too thick on the slide.&#10;B)The slide is placed upside down on the stage.&#10;C)The slide has a coverslip on it.&#10;D)No oil is on the slide.

Accepted Answer

The answer of An image viewed under the microscope is...

Question 13

What is the purpose of the blue filter when using a tungsten-halogen microscope light?&#10;A)eliminate blue color&#10;B)eliminate yellow color&#10;C)reduce light intensity&#10;D)filter out stray light

Accepted Answer

The answer of What is the purpose of the blue...

Question 14

What is the final magnification of an image if the ocular lens is 15* and the objective lens is 50*?&#10;A)*150&#10;B)*500&#10;C)*750&#10;D)*1000

Accepted Answer

The answer of What is the final magnification of an...

Question 15

Match each lettered type of microscope to its clinical use.

Used with fluorochrome dyes to identify lymphocyte subsets

A)Phase contrast
B)Darkfield
C)Polarized light
D)Fluorescent
E)Brightfield

Accepted Answer

The answer of Match each lettered type of microscope to...

Question 16

Which of the following microscopic procedures requires high contrast and lower light?&#10;A)examining unstained objects (e.g., urine sediments)&#10;B)evaluating red cell morphology&#10;C)manual differentials&#10;D)platelet estimates

Accepted Answer

The answer of Which of the following microscopic procedures requires...

Question 17

Koehler illumination&#10;A)is best achieved using a tungsten-halogen light bulb.&#10;B)allows the brightest amount of light to be in the center of a field.&#10;C)adjusts for even light across a field.&#10;D)changes the intensity of the light across a field.

Accepted Answer

The answer of Koehler illumination&#10;A)is best achieved using a tungsten-halogen...

Question 18

What can increase the resolution of an object under the microscope?&#10;A)lowering the condenser&#10;B)increasing the combined magnification provided by the ocular and objective lenses&#10;C)enlarging the numeric aperture of the objective lens&#10;D)adjusting the focus controls

Accepted Answer

The answer of What can increase the resolution of an...

Question 19

What converts for curvature in a field so that a flat field with uniform focus is seen?&#10;A)achromatic objective lens&#10;B)plan-achromatic objective lens&#10;C)spherical correction ocular lens&#10;D)blue filter when placed above the condenser

Accepted Answer

The answer of What converts for curvature in a field...

Question 20

What type of microscope helps in the identification of urine crystals?&#10;A)compound brightfield&#10;B)phase contrast&#10;C)polarized light&#10;D)darkfield

Accepted Answer

The answer of What type of microscope helps in the...

Question 21

Match each lettered type of microscope to its clinical use.

Used with fluorochrome dyes to identify lymphocyte subsets

A)Phase contrast
B)Darkfield
C)Polarized light
D)Fluorescent
E)Brightfield

Accepted Answer

The answer of Match each lettered type of microscope to...

Question 22

Match each lettered type of microscope to its clinical use.&#10;&#10;Counting platelets manually&#10;A)Phase contrast&#10;B)Darkfield&#10;C)Polarized light&#10;D)Fluorescent&#10;E)Brightfield&#10;

Accepted Answer

The answer of Match each lettered type of microscope to...

Question 23

Match each lettered type of microscope to its clinical use.&#10;&#10;Routine differentials&#10;A)Phase contrast&#10;B)Darkfield&#10;C)Polarized light&#10;D)Fluorescent&#10;E)Brightfield&#10;

Accepted Answer

The answer of Match each lettered type of microscope to...

Question 24

Match each lettered type of microscope to its clinical use.

Used with fluorochrome dyes to identify lymphocyte subsets

A)Phase contrast
B)Darkfield
C)Polarized light
D)Fluorescent
E)Brightfield

Accepted Answer

The answer of Match each lettered type of microscope to...

Deck 4: Care and Use of the Microscope