NASM
MLS (ASCP) Hematology Exam Study Guide
Questions with Detailed Answers 2025
Variation in red cell size observed on the peripheral smear is described as:
A. Anisocytosis
B. Hypochromia
C. Poikilocytosis
D. Pleocytosis -Correct Answer ✔A. Anisocytosis
A mature erythrocyte is approximately 7-8um in diameter. Variation in normal size
is denoted by the term anisocytosis. Hypochromia is a term that indicates increased
central pallor in erythrocytes, and poikilocytosis denotes variation in red cell
shape.
Which of the following is the preferable site for bone marrow aspiration and
biopsy in an adult?
A. Iliac crest
B. Sternum
C. Tibia
D. Spinous processes of a vertebra -Correct Answer ✔A. Iliac crest
The iliac crest is the most frequently used site for bone marrow aspiration and
biopsy. This site is the safest and most easily accessible, with the bone just beneath
the skin, and neither blood vessels nor nerves are in the vicinity.
Mean cell volume (MCV) is calculated using the following formula:
NASM
,NASM
A. (Hgb/RBC) x 10
B. (Hct/RBC) x 10
C. (Hct/Hgb) x 100
D. (Hgb/RBC) x 100 -Correct Answer ✔B. (Hct/RBC) x 10
MCV is the average "volume" of the red cells. This is obtained by dividing the Hct
or packed cell volume (PCV) by the red blood cell (RBC) count in millions per
microliter of blood and multiplying by 10. The MCV is expressed in cubic microns
(um^3) or femtoliters (fL).
What term describes the change in shape of erythrocytes seen on a Wright's -
stained peripheral blood smear?
A. Poikilocytosis
B. Anisocytosis
C. Hypochromia
D. Polychromasia -Correct Answer ✔A. Poikilocytosis
Variation in shape of the erythrocytes on a peripheral blood smear is poikilocytosis.
Anisocytosis refers to a change in size. Hypochromia is an increase in central
pallor in erythrocytes. Polychromasia describes the bluish tinge of the immature
erythrocytes (reticulocytes) circulating in the peripheral blood.
Calculate the mean cell hemoglobin concentration (MCHC) using the following
values:
_______________________________________________
Hgb: 15 g/dL (150 g/L)
RBC: 4.50 x 10^6/uL (4.50 x 10^12/L)
NASM
, NASM
Hct: 47 mL/dL (0.47)
_______________________________________________
A. 9.5% (.095)
B. 10.4% (.104)
C. 31.9% (.319)
D. 33.3% (.333) -Correct Answer ✔C. 31.9% (.319)
MCHC is the average concentration of Hgb in red cells expressed as a percentage.
It expresses the ratio of the weight of Hgb to the volume of erythrocytes and is
calculated by dividing Hgb by the Hct, and then multiplying by 100. A decreased
MCHC indicates that cells are hypochromic. In this example, (15/47) x 100 =
31.9%. The reference range for MCHC is 32%=36%.
A manual white blood cell (WBC) count was performed. A total of 36 cells were
counted in all 9-mm^2 squares of a Neubauer-ruled hemacytometer. A 1:10
dilution was used. What is the WBC count?
A. 0.4 x 10^9/L
B. 2.5 x 10^9/L
C. 4.0 x 10^9/L
D. 8.0 x 10 ^9/L -Correct Answer ✔A. 0.4 x 10^9/L
The formula used for calculating manual cell counts using a hemacytometer is:
Number of cells counted x dilution factor x depth factor (10) dividied by the area.
In this example, 36 x 10 x 10 = 3600/9 = 400/mm^3 or 0.4 x 10^9/L
When an erythrocytes containing iron granules is stained with Prussian blue, the
cell is called a:
NASM
MLS (ASCP) Hematology Exam Study Guide
Questions with Detailed Answers 2025
Variation in red cell size observed on the peripheral smear is described as:
A. Anisocytosis
B. Hypochromia
C. Poikilocytosis
D. Pleocytosis -Correct Answer ✔A. Anisocytosis
A mature erythrocyte is approximately 7-8um in diameter. Variation in normal size
is denoted by the term anisocytosis. Hypochromia is a term that indicates increased
central pallor in erythrocytes, and poikilocytosis denotes variation in red cell
shape.
Which of the following is the preferable site for bone marrow aspiration and
biopsy in an adult?
A. Iliac crest
B. Sternum
C. Tibia
D. Spinous processes of a vertebra -Correct Answer ✔A. Iliac crest
The iliac crest is the most frequently used site for bone marrow aspiration and
biopsy. This site is the safest and most easily accessible, with the bone just beneath
the skin, and neither blood vessels nor nerves are in the vicinity.
Mean cell volume (MCV) is calculated using the following formula:
NASM
,NASM
A. (Hgb/RBC) x 10
B. (Hct/RBC) x 10
C. (Hct/Hgb) x 100
D. (Hgb/RBC) x 100 -Correct Answer ✔B. (Hct/RBC) x 10
MCV is the average "volume" of the red cells. This is obtained by dividing the Hct
or packed cell volume (PCV) by the red blood cell (RBC) count in millions per
microliter of blood and multiplying by 10. The MCV is expressed in cubic microns
(um^3) or femtoliters (fL).
What term describes the change in shape of erythrocytes seen on a Wright's -
stained peripheral blood smear?
A. Poikilocytosis
B. Anisocytosis
C. Hypochromia
D. Polychromasia -Correct Answer ✔A. Poikilocytosis
Variation in shape of the erythrocytes on a peripheral blood smear is poikilocytosis.
Anisocytosis refers to a change in size. Hypochromia is an increase in central
pallor in erythrocytes. Polychromasia describes the bluish tinge of the immature
erythrocytes (reticulocytes) circulating in the peripheral blood.
Calculate the mean cell hemoglobin concentration (MCHC) using the following
values:
_______________________________________________
Hgb: 15 g/dL (150 g/L)
RBC: 4.50 x 10^6/uL (4.50 x 10^12/L)
NASM
, NASM
Hct: 47 mL/dL (0.47)
_______________________________________________
A. 9.5% (.095)
B. 10.4% (.104)
C. 31.9% (.319)
D. 33.3% (.333) -Correct Answer ✔C. 31.9% (.319)
MCHC is the average concentration of Hgb in red cells expressed as a percentage.
It expresses the ratio of the weight of Hgb to the volume of erythrocytes and is
calculated by dividing Hgb by the Hct, and then multiplying by 100. A decreased
MCHC indicates that cells are hypochromic. In this example, (15/47) x 100 =
31.9%. The reference range for MCHC is 32%=36%.
A manual white blood cell (WBC) count was performed. A total of 36 cells were
counted in all 9-mm^2 squares of a Neubauer-ruled hemacytometer. A 1:10
dilution was used. What is the WBC count?
A. 0.4 x 10^9/L
B. 2.5 x 10^9/L
C. 4.0 x 10^9/L
D. 8.0 x 10 ^9/L -Correct Answer ✔A. 0.4 x 10^9/L
The formula used for calculating manual cell counts using a hemacytometer is:
Number of cells counted x dilution factor x depth factor (10) dividied by the area.
In this example, 36 x 10 x 10 = 3600/9 = 400/mm^3 or 0.4 x 10^9/L
When an erythrocytes containing iron granules is stained with Prussian blue, the
cell is called a:
NASM
