Question 1

Which of the following is an important rule to follow when enumerating leukocytes?

Accepted Answer

A)  The difference between any two counts should be less than 10, and the difference between the highest and lowest count should be less than 15. 
B)  The mean of the four counts on one side of the hemacytometer should be less than 10 units different from the mean of the four counts on the other side of the hemacytometer. 
C)  The total count from one side of the hemacytometer should differ from the total count on the other side of the hemacytometer by at least 20. 
D)  The values obtained from one side of the hemacytometer should be identical to those obtained from the other side of the hemacytometer. 
A)  The difference between any two counts should be less than 10, and the difference between the highest and lowest count should be less than 15. 
B)  The mean of the four counts on one side of the hemacytometer should be less than 10 units different from the mean of the four counts on the other side of the hemacytometer. 
C)  The total count from one side of the hemacytometer should differ from the total count on the other side of the hemacytometer by at least 20. 
D)  The values obtained from one side of the hemacytometer should be identical to those obtained from the other side of the hemacytometer. A

Question 2

An anemic patient has a reticulocyte production index (RPI)of 1.What does this value suggest?

Accepted Answer

A)  Erythropoiesis is inadequate and indicative of possible pathology. 
B)  Erythropoiesis is occurring at a rate equal to red blood cell degradation. 
C)  Erythropoiesis is proceeding at a normal rate. 
D)  Both B and C are correct. 
A)  Erythropoiesis is inadequate and indicative of possible pathology. 
B)  Erythropoiesis is occurring at a rate equal to red blood cell degradation. 
C)  Erythropoiesis is proceeding at a normal rate. 
D)  Both B and C are correct. A

Question 3

In order to correct a white blood cell (WBC)count for the presence of nucleated red blood cells (nRBCs),what information must be collected?

Accepted Answer

A)  The average cell volume of nRBCs and WBCs 
B)  The number of nRBCs per 100 WBCs 
C)  The number of nRBCs per 1000 RBCs 
D)  The volume of nRBC in 100 mL whole blood 
A)  The average cell volume of nRBCs and WBCs 
B)  The number of nRBCs per 100 WBCs 
C)  The number of nRBCs per 1000 RBCs 
D)  The volume of nRBC in 100 mL whole blood B

Question 4

A low hematocrit value generally suggests

Accepted Answer

A)  anemia. 
B)  hemophilia. 
C)  leukemia. 
D)  neutropenia. 
A)  anemia. 
B)  hemophilia. 
C)  leukemia. 
D)  neutropenia.

Question 5

Why is it important to standardize the results of a prothrombin time (PT)test?

Accepted Answer

A)  To account for the wide variation in commercial preparations of thromboplastin and the differences in instrumentation 
B)  To introduce a proportionality constant that ensures the results will fit onto the standard curve 
C)  To eliminate interference by anticoagulant drugs 
D)  None of the above 
A)  To account for the wide variation in commercial preparations of thromboplastin and the differences in instrumentation 
B)  To introduce a proportionality constant that ensures the results will fit onto the standard curve 
C)  To eliminate interference by anticoagulant drugs 
D)  None of the above

Question 6

What does the mean cell volume (MCV)of a sample tell us?

Accepted Answer

A)  The average volume of the red blood cells 
B)  The concentration of abnormal platelets 
C)  The percentage of healthy versus abnormal red blood cells 
D)  The volume of non-nucleated white blood cells 
A)  The average volume of the red blood cells 
B)  The concentration of abnormal platelets 
C)  The percentage of healthy versus abnormal red blood cells 
D)  The volume of non-nucleated white blood cells

Question 7

Reticulocytes are immature red blood cells that contain residual ribosomal RNA.What does counting reticulocytes tell us about a patient?

Accepted Answer

A)  The blood type of the patient 
B)  The effectiveness of erythrocyte production 
C)  The severity of a patient's anisocytosis 
D)  The volume of red blood cells in whole blood 
A)  The blood type of the patient 
B)  The effectiveness of erythrocyte production 
C)  The severity of a patient's anisocytosis 
D)  The volume of red blood cells in whole blood

Question 8

What is the dilution factor for enumerating erythrocytes?

Accepted Answer

A)  1:2 
B)  1:20 
C)  1:100 
D)  1:200 
A)  1:2 
B)  1:20 
C)  1:100 
D)  1:200

Question 9

What is the hematocrit?

Accepted Answer

A)  The concentration of platelets found in a blood sample 
B)  The mass percentage of blood made up of red and white blood cells 
C)  The ratio of the number of white blood cells to the number of platelets 
D)  The volume of whole blood occupied by packed red blood cells 
A)  The concentration of platelets found in a blood sample 
B)  The mass percentage of blood made up of red and white blood cells 
C)  The ratio of the number of white blood cells to the number of platelets 
D)  The volume of whole blood occupied by packed red blood cells

Question 10

What is necessary when performing an osmotic fragility test?

Accepted Answer

A)  A series of hypertonic solutions 
B)  A series of hypotonic solutions 
C)  A solution 98% solution of NaCl (w/v) and methylene blue stain 
D)  A solution of NaCl and a solution of FeCl₂ of equal concentration 
A)  A series of hypertonic solutions 
B)  A series of hypotonic solutions 
C)  A solution 98% solution of NaCl (w/v) and methylene blue stain 
D)  A solution of NaCl and a solution of FeCl₂ of equal concentration

Question 11

A patient is suspected of having severe anemia.His hematocrit is 18%,reticulocyte count is 12%,and red blood cell count is 2.2 × 10⁶ cells/μL.A normal hematocrit is taken as 45%.Which of the following expressions should be used to calculate the patient's reticulocyte index?

Accepted Answer

A)  (2.2 × 10⁶) × $ \frac{12}{18} $ 
B)  (2.2 × 10⁶) × $ \frac{18+12}{45} $ 
C)  12 × $ \frac{18}{45} $ 
D)  18 × 18 - 2.2 × 10⁶ 
A)  (2.2 × 10⁶) × $ \frac{12}{18} $ 
B)  (2.2 × 10⁶) × $ \frac{18+12}{45} $ 
C)  12 × $ \frac{18}{45} $ 
D)  18 × 18 - 2.2 × 10⁶

Question 12

You are asked to test the osmotic fragility of a patient's red blood cells (RBCs).After calculating the percent lysis,you plot the results.The patient's lysis curve is significantly shifted to the left of the normal curve.What does this indicate?

Accepted Answer

A)  The patient's RBCs have a high osmotic fragility, consistent with the presence of spherocytes. 
B)  The patient's RBCs have a high osmotic fragility, consistent with the presence of target cells. 
C)  The patient's RBCs have a low osmotic fragility, consistent with the presence of spherocytes. 
D)  The patient's RBCs have a low osmotic fragility, consistent with the presence of target cells. 
A)  The patient's RBCs have a high osmotic fragility, consistent with the presence of spherocytes. 
B)  The patient's RBCs have a high osmotic fragility, consistent with the presence of target cells. 
C)  The patient's RBCs have a low osmotic fragility, consistent with the presence of spherocytes. 
D)  The patient's RBCs have a low osmotic fragility, consistent with the presence of target cells.

Question 13

When a Miller disk is used to enumerate reticulocytes,which of the following counts are needed?

Accepted Answer

A)  The number of red blood cells in both squares, and the number of reticulocytes in both squares 
B)  The number of red blood cells in both squares, and the number of reticulocytes in the small square 
C)  The number of red blood cells in the small square, and the number of reticulocytes in both squares 
D)  The number of red blood cells in the small square, and the number of reticulocytes in the small square 
A)  The number of red blood cells in both squares, and the number of reticulocytes in both squares 
B)  The number of red blood cells in both squares, and the number of reticulocytes in the small square 
C)  The number of red blood cells in the small square, and the number of reticulocytes in both squares 
D)  The number of red blood cells in the small square, and the number of reticulocytes in the small square

Question 14

A set of results that fails the Rule of Three may indicate that

Accepted Answer

A)  the patient has a pathological condition. 
B)  the ratio of white blood cells to red blood cells is abnormal. 
C)  the red blood cells in the sample have all lysed. 
D)  the volume of blood obtained from the patient is insufficient for analysis. 
A)  the patient has a pathological condition. 
B)  the ratio of white blood cells to red blood cells is abnormal. 
C)  the red blood cells in the sample have all lysed. 
D)  the volume of blood obtained from the patient is insufficient for analysis.

Question 15

What would a hematocrit of 24% indicate?

Accepted Answer

A)  Red blood cells occupy 24 mL of every 100 mL of whole blood. 
B)  The platelets in a blood sample are 24% larger in volume than a normal platelet. 
C)  There are 24 red blood cells for every 100 white blood cells in a blood sample. 
D)  White blood cells make up 24 of every 100 cells present in whole blood. 
A)  Red blood cells occupy 24 mL of every 100 mL of whole blood. 
B)  The platelets in a blood sample are 24% larger in volume than a normal platelet. 
C)  There are 24 red blood cells for every 100 white blood cells in a blood sample. 
D)  White blood cells make up 24 of every 100 cells present in whole blood.

Question 16

A clinical laboratory technician is asked to enumerate the red blood cells in a sample using the standard procedure.What is the single factor by which the technician can multiply the absolute number of cells counted on the hemacytometer to obtain an accurate final count?

Accepted Answer

A)  50 
B)  200 
C)  1,000 
D)  10,000 
A)  50 
B)  200 
C)  1,000 
D)  10,000

Question 17

Which of the following features about a thromboplastin preparation is necessary for accurate results?

Accepted Answer

A)  Serial dilutions must be made of the thromboplastin preparation and measured to create a standard curve. 
B)  The international sensitivity index (ISI) of the thromboplastin preparation should be close to 1. 
C)  The thromboplastin preparation must be made by and purchased from the International Standardization Committee. 
D)  The thromboplastin preparation must be tested and certified by the World Health Organization (WHO). 
A)  Serial dilutions must be made of the thromboplastin preparation and measured to create a standard curve. 
B)  The international sensitivity index (ISI) of the thromboplastin preparation should be close to 1. 
C)  The thromboplastin preparation must be made by and purchased from the International Standardization Committee. 
D)  The thromboplastin preparation must be tested and certified by the World Health Organization (WHO).

Question 18

A clinical laboratory technician is asked to determine the concentration of red blood cells (RBCs)from a sample of turbid knee fluid using a hemacytometer.The technician dilutes the sample with normal saline and loads it onto the hemacytometer.A total of 400 red blood cells are counted over 5 squares.What additional information is required to calculate the concentration of RBCs?

Accepted Answer

A)  The WBC count 
B)  The dilution factor 
C)  The number of platelets 
D)  The red-cell distribution width 
A)  The WBC count 
B)  The dilution factor 
C)  The number of platelets 
D)  The red-cell distribution width

Which of the following is an important rule to follow when enumerating leukocytes?

An anemic patient has a reticulocyte production index (RPI)of 1.What does this value suggest?

In order to correct a white blood cell (WBC)count for the presence of nucleated red blood cells (nRBCs),what information must be collected?

A low hematocrit value generally suggests

Why is it important to standardize the results of a prothrombin time (PT)test?

What does the mean cell volume (MCV)of a sample tell us?

Reticulocytes are immature red blood cells that contain residual ribosomal RNA.What does counting reticulocytes tell us about a patient?

What is the dilution factor for enumerating erythrocytes?

What is the hematocrit?

What is necessary when performing an osmotic fragility test?

A patient is suspected of having severe anemia.His hematocrit is 18%,reticulocyte count is 12%,and red blood cell count is 2.2 × 10⁶ cells/μL.A normal hematocrit is taken as 45%.Which of the following expressions should be used to calculate the patient's reticulocyte index?

You are asked to test the osmotic fragility of a patient's red blood cells (RBCs).After calculating the percent lysis,you plot the results.The patient's lysis curve is significantly shifted to the left of the normal curve.What does this indicate?

When a Miller disk is used to enumerate reticulocytes,which of the following counts are needed?

A set of results that fails the Rule of Three may indicate that

What would a hematocrit of 24% indicate?

A clinical laboratory technician is asked to enumerate the red blood cells in a sample using the standard procedure.What is the single factor by which the technician can multiply the absolute number of cells counted on the hemacytometer to obtain an accurate final count?

Which of the following features about a thromboplastin preparation is necessary for accurate results?

Arithmetic and Algebra

Exponential Notation & Logarithms

Rounding and the Significance of Figures

Systems of Measurement

Solutions and Concentrations

Dilutions

Proportionality, Graphs, and Rates of Change

Statistics

Chemistry

Quality Control

Method Evaluation

Filters

Exam 10: Hematology

Which of the following is an important rule to follow when enumerating leukocytes?

An anemic patient has a reticulocyte production index (RPI)of 1.What does this value suggest?

In order to correct a white blood cell (WBC)count for the presence of nucleated red blood cells (nRBCs),what information must be collected?

A low hematocrit value generally suggests

Why is it important to standardize the results of a prothrombin time (PT)test?

What does the mean cell volume (MCV)of a sample tell us?

Reticulocytes are immature red blood cells that contain residual ribosomal RNA.What does counting reticulocytes tell us about a patient?

What is the dilution factor for enumerating erythrocytes?

What is the hematocrit?

What is necessary when performing an osmotic fragility test?

A patient is suspected of having severe anemia.His hematocrit is 18%,reticulocyte count is 12%,and red blood cell count is 2.2 × 10⁶ cells/μL.A normal hematocrit is taken as 45%.Which of the following expressions should be used to calculate the patient's reticulocyte index?

You are asked to test the osmotic fragility of a patient's red blood cells (RBCs).After calculating the percent lysis,you plot the results.The patient's lysis curve is significantly shifted to the left of the normal curve.What does this indicate?

When a Miller disk is used to enumerate reticulocytes,which of the following counts are needed?

A set of results that fails the Rule of Three may indicate that

What would a hematocrit of 24% indicate?

A clinical laboratory technician is asked to enumerate the red blood cells in a sample using the standard procedure.What is the single factor by which the technician can multiply the absolute number of cells counted on the hemacytometer to obtain an accurate final count?

Which of the following features about a thromboplastin preparation is necessary for accurate results?

Arithmetic and Algebra

Exponential Notation & Logarithms

Rounding and the Significance of Figures

Systems of Measurement

Solutions and Concentrations

Dilutions

Proportionality, Graphs, and Rates of Change

Statistics

Chemistry

Quality Control

Method Evaluation

Filters