UAMS Hematology lab final UPDATED
ACTUAL Exam Questions and CORRECT
Answers
What is the smear prep process? - CORRECT ANSWER - Place drop of blood from
EDTA tube on with 1/2 inch from the frosted end of a slide. Lay the slide on a flat surface. Place
the end of a second (spreader) slide, held with the fingertips at an angle of 30-45 degrees, in front
of the drop of blood. Pull the spreader slide back into the drop of blood. Allow blood to spread
entire width of slide. Quickly and smoothly push the spreader slide forward.
What tools do you need to prepare a smear? - CORRECT ANSWER - Glass slides, blood,
cover slip
What causes a bad smear? - CORRECT ANSWER - Dirty slide, jerky motion, pointed
feather edge, angle of the spreader slide too steep, did not allow blood to spread, high level of
lipids, unequal pressure.
What is the coverslip smear used for? - CORRECT ANSWER - Used for making bone
marrow preps.
What are the items needed for the Wright's stain? - CORRECT ANSWER - Stain: To stain
the RBCs and WBCs
Buffer:
Methanol:
What are the sources of error when staining a smear? - CORRECT ANSWER - Stain or
buffer is too acidic or alkaline, prolonged staining, heparinized blood sample, prolonged rinsing,
under-buffering.
Excessively blue slides may be due to: - CORRECT ANSWER - Smear being too thick
Prolonged staining time
,Excessively red (pink slides) may be due to: - CORRECT ANSWER - Insufficient staining
time
Prolonged washing
Precipitated stain on blood smear may be due to: - CORRECT ANSWER - Unfiltered
wright stain
Wright's stain dried on smear in staining process
Incomplete washing off of greenish sheen
Unleveled staining will cause stain to: - CORRECT ANSWER - Run off slide
Smear may be under-stained
Appropriate action for appearance of water artifacts on the smear (appearance of moth water
look to RBCs, refractive blotches on the RBCs, crenation appearance of RBCs) - CORRECT
ANSWER - Dry slides as quickly as possible
Fix slides with methanol
What is a good area when viewing a blood smear? - CORRECT ANSWER - Cells should
be touching each other with minimal overlap.
How do you perform a WBC estimate? - CORRECT ANSWER - Select a good area on
slide. Average the number of white cells in five low power fields. Multiply the average by 200.
(One white cell under low power, 10x, equals approximately 200 WBCs)
How do you check for platelet clumps? - CORRECT ANSWER - Check for platelet
clumps after performing WBC estimate. Look at the feather edge or side margins of the smear.
Agglutination of cells or clotting of the blood may be due to: - CORRECT ANSWER -
Mixing delay
,If you can't get your slide to focus, what are the potential issues? - CORRECT ANSWER -
The slide is upside down. A drop of oil wasn't added to the slide. The coarse adjust knob has
been turned too far one way or another.
What is a good area in oil immersion? - CORRECT ANSWER - Cells touching with
minimal overlap. Approximately 200 RBCs per oil field.
What do we look at under oil immersion? - CORRECT ANSWER - We look at the
morphology of the red blood cells, we identify and differentiate white blood cells, and we
observed platelets for number, size, and morphology.
How do you perform a platelet estimate? - CORRECT ANSWER - Average the platelet
number in 5 oil fields. Multiply by 20,000.
What will the slide look like if the sample is too old? How old is too old? - CORRECT
ANSWER - WBCs break up or disintegrate; vacuoles may appear. Platelets begin to
clump. Red cells change size and shaped, especially forming crenation. A sample is too old when
it remains at room temperature for more than 5 hours.
What is the difference between agglutination and rouleaux? - CORRECT ANSWER -
Rouleaux are orderly linear stacks of RBCs, whereas RBC agglutination is formed by grapelike
RBC aggregates.
Describe the microscopic appearance of a well-made, well stained peripheral smear. -
CORRECT ANSWER - RBC should appear pink, orange to salmon pink
WBC nuclei should be purple to blue
Cytoplasm of neutrophils should be pink to tan with lavendar or lilac granules
Eosinophils should have bright orange refractile granules
Describe the macroscopic appearance of a well-made, well stained smear - CORRECT
ANSWER - Pink to purple in color
, Contain a smooth feathered edge
The smear should cover two thirds of the area of the slide
RBCs appear gray and WBC are too dark (excessively blue) - CORRECT ANSWER -
Decrease Staining Time
Red blood cels too pale or appear red and WBCs are barely visible - CORRECT
ANSWER - Increase staining time, decrease rinsing time
Appearance of water artifacts on the smear (appearance of moth eaten to look to RBCs,
refractive blotches on the RBC, crenation appearance of RBCs) - CORRECT ANSWER -
Dry slides as quickly as possible or fix slides with methanol
What is the final magnification when using oil power? - CORRECT ANSWER - 1000x
Order of Sequence in which objects are used when examining a peripheral smear - CORRECT
ANSWER - First: 10x
Second: 40x
Third: 100x
Match the objective to its correct purpose during a peripheral blood file examination: 10x -
CORRECT ANSWER - Select a good area. WBC distribution and RBC distribution.
Quick scan for any abnormal cells such as blast, reactive lymphs, or parasites
Match the objective to its correct purpose during a peripheral blood file examination: 40x -
CORRECT ANSWER - WBC estimate, RBCBs should be evenly distributed (2-3 may
overlap)
Match the objective to its correct purpose during a peripheral blood file examination: 100x -
CORRECT ANSWER - Identify WBCs for differential, observe platelets (estimate
number, size, morphology)
ACTUAL Exam Questions and CORRECT
Answers
What is the smear prep process? - CORRECT ANSWER - Place drop of blood from
EDTA tube on with 1/2 inch from the frosted end of a slide. Lay the slide on a flat surface. Place
the end of a second (spreader) slide, held with the fingertips at an angle of 30-45 degrees, in front
of the drop of blood. Pull the spreader slide back into the drop of blood. Allow blood to spread
entire width of slide. Quickly and smoothly push the spreader slide forward.
What tools do you need to prepare a smear? - CORRECT ANSWER - Glass slides, blood,
cover slip
What causes a bad smear? - CORRECT ANSWER - Dirty slide, jerky motion, pointed
feather edge, angle of the spreader slide too steep, did not allow blood to spread, high level of
lipids, unequal pressure.
What is the coverslip smear used for? - CORRECT ANSWER - Used for making bone
marrow preps.
What are the items needed for the Wright's stain? - CORRECT ANSWER - Stain: To stain
the RBCs and WBCs
Buffer:
Methanol:
What are the sources of error when staining a smear? - CORRECT ANSWER - Stain or
buffer is too acidic or alkaline, prolonged staining, heparinized blood sample, prolonged rinsing,
under-buffering.
Excessively blue slides may be due to: - CORRECT ANSWER - Smear being too thick
Prolonged staining time
,Excessively red (pink slides) may be due to: - CORRECT ANSWER - Insufficient staining
time
Prolonged washing
Precipitated stain on blood smear may be due to: - CORRECT ANSWER - Unfiltered
wright stain
Wright's stain dried on smear in staining process
Incomplete washing off of greenish sheen
Unleveled staining will cause stain to: - CORRECT ANSWER - Run off slide
Smear may be under-stained
Appropriate action for appearance of water artifacts on the smear (appearance of moth water
look to RBCs, refractive blotches on the RBCs, crenation appearance of RBCs) - CORRECT
ANSWER - Dry slides as quickly as possible
Fix slides with methanol
What is a good area when viewing a blood smear? - CORRECT ANSWER - Cells should
be touching each other with minimal overlap.
How do you perform a WBC estimate? - CORRECT ANSWER - Select a good area on
slide. Average the number of white cells in five low power fields. Multiply the average by 200.
(One white cell under low power, 10x, equals approximately 200 WBCs)
How do you check for platelet clumps? - CORRECT ANSWER - Check for platelet
clumps after performing WBC estimate. Look at the feather edge or side margins of the smear.
Agglutination of cells or clotting of the blood may be due to: - CORRECT ANSWER -
Mixing delay
,If you can't get your slide to focus, what are the potential issues? - CORRECT ANSWER -
The slide is upside down. A drop of oil wasn't added to the slide. The coarse adjust knob has
been turned too far one way or another.
What is a good area in oil immersion? - CORRECT ANSWER - Cells touching with
minimal overlap. Approximately 200 RBCs per oil field.
What do we look at under oil immersion? - CORRECT ANSWER - We look at the
morphology of the red blood cells, we identify and differentiate white blood cells, and we
observed platelets for number, size, and morphology.
How do you perform a platelet estimate? - CORRECT ANSWER - Average the platelet
number in 5 oil fields. Multiply by 20,000.
What will the slide look like if the sample is too old? How old is too old? - CORRECT
ANSWER - WBCs break up or disintegrate; vacuoles may appear. Platelets begin to
clump. Red cells change size and shaped, especially forming crenation. A sample is too old when
it remains at room temperature for more than 5 hours.
What is the difference between agglutination and rouleaux? - CORRECT ANSWER -
Rouleaux are orderly linear stacks of RBCs, whereas RBC agglutination is formed by grapelike
RBC aggregates.
Describe the microscopic appearance of a well-made, well stained peripheral smear. -
CORRECT ANSWER - RBC should appear pink, orange to salmon pink
WBC nuclei should be purple to blue
Cytoplasm of neutrophils should be pink to tan with lavendar or lilac granules
Eosinophils should have bright orange refractile granules
Describe the macroscopic appearance of a well-made, well stained smear - CORRECT
ANSWER - Pink to purple in color
, Contain a smooth feathered edge
The smear should cover two thirds of the area of the slide
RBCs appear gray and WBC are too dark (excessively blue) - CORRECT ANSWER -
Decrease Staining Time
Red blood cels too pale or appear red and WBCs are barely visible - CORRECT
ANSWER - Increase staining time, decrease rinsing time
Appearance of water artifacts on the smear (appearance of moth eaten to look to RBCs,
refractive blotches on the RBC, crenation appearance of RBCs) - CORRECT ANSWER -
Dry slides as quickly as possible or fix slides with methanol
What is the final magnification when using oil power? - CORRECT ANSWER - 1000x
Order of Sequence in which objects are used when examining a peripheral smear - CORRECT
ANSWER - First: 10x
Second: 40x
Third: 100x
Match the objective to its correct purpose during a peripheral blood file examination: 10x -
CORRECT ANSWER - Select a good area. WBC distribution and RBC distribution.
Quick scan for any abnormal cells such as blast, reactive lymphs, or parasites
Match the objective to its correct purpose during a peripheral blood file examination: 40x -
CORRECT ANSWER - WBC estimate, RBCBs should be evenly distributed (2-3 may
overlap)
Match the objective to its correct purpose during a peripheral blood file examination: 100x -
CORRECT ANSWER - Identify WBCs for differential, observe platelets (estimate
number, size, morphology)
