Ascp Certification Exam

Front 1

What is hemoglobin composed of?

Back 1

4 heme, 4 iron, 1 globin

Front 2

What disorder does defect in heme synthesis lead to?

Back 2

porphyria

Front 3

What is the function of the enzyme methemoglobin-cytochrome C reductase in red blood cell?

Back 3

to keep iron in ferrous state

Front 4

Which hemoglobin has a 200 times greater binding capacity for the hemoglobin molecule than oxygen?

Back 4

carboxyhemoglobin

Front 5

What product is formed when ferrous iron of hemoglobin is oxidized to the ferric state?

Back 5

methemoglobin

Front 6

Which hemoglobin derivative causes irreversible changes in the red blood cells?

Back 6

sulfhemoglobin

Front 7

Which of the following hemoglobins is NOT normally present in a normal adult?

Back 7

Hb-S

Front 8

Which embryonic hemoglobin is normally found in newborns?

Back 8

Hb-F

Front 9

What is the most abundant hemoglobin in a newborn?

Back 9

Hb-F

Front 10

What is the molecular structure of hemoglobin S?

Back 10

valine replaces gultamic acid in the 6th position of the beta chain

Front 11

Which of the following hemoglobins is insoluble under lowered oxygen tension?

Back 11

Hb-S

Front 12

What laboratory test is used to confirm the specific diagnosis of sickle cell anemia?

Back 12

hemoglobin electrophoresis

Front 13

In the solubility test for hemoglobin S, what is the reagent responsible for the reduction of hemoglobin molecule?

Back 13

sodium dithionite

Front 14

In hemoglobin C, what replaces glutamic acid?

Back 14

lysine

Front 15

Which red blood cell inclusion is characteristic of hemoglobin C disease?

Back 15

rod-shaped crystals

Front 16

What is hemoglobin F composed of?

Back 16

2 alpha + 2 gamma chains

Front 17

Which hemoglobin is resistant to alkali denaturation?

Back 17

Hb-F

Front 18

What hemoglobins are differentiated by the Kleihauer-Betke technique?

Back 18

Hb-A1 from Hb-F

Front 19

What is the order of migration of hemoglobins, from fastest to slowest, on cellulose acetate at pH 8.4?

Back 19

A1, F, S, C

Front 20

Why is citrate agar used when abnormal hemoglobins are identified on cellulose acetate at pH 8.6?

Back 20

It separates hemoglobin S from hemoglobin D

Front 21

The cyanmethemoglobin method measures all hemoglobin pigments EXCEPT which one?

Back 21

sulfhemoglobin

Front 22

What is the diluent used in the cyanmethemoglobin method for the determination of hemoglobin?

Back 22

Drabkin's solution

Front 23

What is the normal plasma hemoglobin concentration?

Back 23

2-3 mg/dL

Front 24

Which plasma protein binds free hemoglobin?

Back 24

haptoglobin

Front 25

Which one of the following statements concerning hemolytic anemia is false?

Back 25

The serum haptoglobin is increased

Front 26

Myoglobin can be separated from hemoglobin by saturating the specimen with what reagent?

Back 26

ammonium sulfate

Front 27

The hematocrit is also known as what term?

Back 27

packed red blood cell volume

Front 28

The degree of packing of cells during centrifugation depends on?

Back 28

bore size of the microhematocrit tube

Front 29

During examination of a spun hematocrit, in which layer are the white blood cells found?

Back 29

Buffy coat

Front 30

When performing a microhematocrit, where should one read the percentage of packed red blood cell column from a microhematocrit reading device?

Back 30

below the buffy coat

Front 31

An increase in the erythrocyte sedimentation rate can be the result of an increase in the quantity of what?

Back 31

fibrinogen

Front 32

Which test is increased in acute infections?

Back 32

erythrocyte sedimentation rate

Front 33

Which sources of error will falsely elevate the erythrocyte sedimentation rate?

Back 33

tilted tube

macrocytes

vibrations from a nearby centrifuge

Front 34

What is the Westergren ESR reference range for males?

Back 34

0-15 mm/hr

Front 35

A cerebrospinal fluid has 285 red blood cells counted in the 5 red blood cell squares after being diluted in a Unopette (1:100). What is the calculated red blood cell count/uL?

Back 35

1,425,000

Front 36

Any cell that passes through the aperture will momentarily increase the resistance of the electrical flow between the electrodes, generating a pulse. This is the basic principle of what?

Back 36

electrical impedance

Front 37

What principle utilizes laminar flow and hydrodynamic focusing to characterize cell based on granularity and reflectivity?

Back 37

laser light scatter

Front 38

Scatterplots are created using what?

Back 38

scatter

volume

conductivity

Front 39

Both nucleated red blood cells and large platelets interfere with what parameters?

Back 39

WBC

Front 40

Lyse-resistant red blood cells detected by automated hematology analyzers are seen in which clinical condition?

Back 40

sickle cell anemia

Front 41

ON automated hematology analyzers, what will affect both the red blood cell count and the platelet count?

Back 41

schistocytes

Front 42

The white blood cell count is 10.5. There are 5 nucleated red blood cells seen on the 100 cell differential. what is the corrected WBC count?

Back 42

10.0

Front 43

On automated hematology analyzers, hemoglobin determinations may be falsely elevated due to the presence of which one of the following interfering substances?

Back 43

lipemia

Front 44

The following CBC results are obtained:

WBC 6.5

RBC 1.69

HGB 9.1

HCT 22.8

MCV 135.0

MCH 53.8

MCHC 39.9

What is the most likely cause of these results?

Back 44

cold agglutinin

Front 45

What may cause a falsely decreased platelet count?

Back 45

giant platelets

platelet clumps

platelet satellitosis

Front 46

A leukocyte count greater than the linearity of the automated analyzer will falsely elevate what other CBC parameter?

Back 46

HGB

Front 47

Fragile white blood cells seen in leukemia patients may cause pseudoleukopenia, which in turn may cause automated WBC and WBC estimate not to match. What action should be taken if this occurs?

Back 47

perform a manual WBC hematocytometer count

Front 48

What is the dilution factor for performing a platelet count from a sodium citrate tube?

Back 48

1.1

Front 49

What is the formula for correcting a WBC count for the presence of nucleated red blood cell?

Back 49

(WBC X 100)/(nRBC + 100)

Front 50

Smudge cells can cause the automated WBC and the WBC estimate not to match. What action can be taken to prevent this occurrence?

Back 50

add 22% bovine albumin to stabilize the WBC

Front 51

If cryoglobulin causes WBC cellular interference, then what is the most appropriate action to take to resolve this interfering substance?

Back 51

incubate the specimen at 37 degrees C for 15 minutes

Front 52

If a cold agglutinin is suspected to be causing erroneous results, then what is the most appropriate action to take before reporting the results?

Back 52

incubate the specimen at 37 degrees C for 15 minutes

Front 53

After centrifuging a microhematocrit, the presence of lipemia is noted. What is the most appropriate correction action?

Back 53

perform a saline replacement procedure

Front 54

What can produce a normal MCV but hypochromic red blood cells to appear on the peripheral blood smear?

Back 54

hyperglycemia

Front 55

If a WBC count is performed on a 1:100 dilution and the number of cells counted in a total of 8 squares is 50, then what is the WBC count?

Back 55

6,250

Front 56

A blood smear shows 80 nucleated red blood cells per 100 leukocytes. The total leukocyte count is 18.0 x 109/L. What is the corrected WBC count?

Back 56

10.0

Front 57

What reagent is the fixative incorporated in the Wright's stain?

Back 57

methanol

Front 58

How can the color of Wright-stained red blood cells be adjusted?

Back 58

adjusting the pH of the buffer

Front 59

Malarial parasites in red blood cells are best demonstrated by which stain?

Back 59

Giemsa

Front 60

Which RBC inclusions is NOT visible with Wright Stain?

Back 60

Heinz bodies

Front 61

What is a stain for iron?

Back 61

Prussian blue

Front 62

In which special cytochemical stain are homogeneously pink cells counted as positive?

Back 62

Kleihauer-Betke stain

Front 63

What stains both nonspecific and specific granules in myelogenous cells?

Back 63

Sudan black B

Front 64

IN the cytochemical stain for peroxidase, which cell stains negative?

Back 64

lymphocytes

Front 65

The results on a leukemic patient are as follows:

alpha-naphthol-AS-D-acetate esterase (NASDA) 3+

NASDA with sodium fluoride (NAF) 1+

These results are suggestive of which type of leukemia?

Back 65

AMML

Front 66

In which leukemia are the blasts periodic acid-Schiff (PAS) stain positive?

Back 66

ALL

Front 67

What is a stain for neutral lipids?

Back 67

Oil red O

Front 68

Which stain is used to differentiate chronic myelogenous leukemia (CML) from a leukemoid reaction?

Back 68

leukocyte alkaline phosphatase

Front 69

What stain is positive for hairy cell leukemia?

Back 69

acid phosphatase

Front 70

What is the most reliable criterion for the estimation of a cell's age?

Back 70

nuclear chromatin

Front 71

What is the last red blood cell precursor to retain the nucleus before it becomes an erythrocyte?

Back 71

metarubricyte

Front 72

Which peripheral smear finding is consistent with reticulocytosis?

Back 72

polychormatophilia

Front 73

what is the life span of an erythrocyte?

Back 73

3 months

Front 74

what are indications of anemia?

Back 74

decreased RBC

decreased HGB

decreased HCT

Front 75

What lab results are consistent with anemia?

Back 75

neonate: HGB 17.7 g/dL

adult male: HGB 13.0 g/dL

adult female: HGB 10.9 g/dL

Front 76

The following results were obtained from a CBC specimen:

WBC 10.3 X 10 9/L

RBC 4.19 X 10 12/l

HGB 9.9 g/dL

HCT 27.0%

MCV 95 fl

MCH 33.2 pg

MCHC 33.3%

What is the most probable cause of these results?

Back 76

anemia

Front 77

To calculate the mean corpuscular volume (MCV), what parameters must be known?

Back 77

RBC and HCT

Front 78

Given the following lab results, what is the calculated MCH?

RBC 3.01 x 10 12/L

HGB 9.4 g/dL

HCT 27.5%

Back 78

31.2 pg

Front 79

What is the reference range for the mean corpuscular hemoglobin concentration?

Back 79

32%-36%

Front 80

Which CBC parameter is a numerical expression of anisocytosis?

Back 80

RDW

Front 81

What is the abnormal variation in the size of the erythrocytes known as?

Back 81

anisocytosis

Front 82

Which determination is considered a reliable assessment of effective erythropoiesis in the bone marrow?

Back 82

reticulocyte count

Front 83

To calculate the reticulocyte production index, other than the reticulocyte count (%), what other hematological parameter is needed?

Back 83

HCT

Front 84

What are the erythrocytes with a diameter of 9 to 12 microns referred to as?

Back 84

macrocytes

Front 85

What causes the red cell color of immature erythrocytes to appear polychromatophilic?

Back 85

residual RNA

Front 86

What is abnormal variation in the shape of the erythrocytes known as?

Back 86

poikilocytosis

Front 87

What does the peripheral blood smear show in a patient with iron deficiency anemia?

Back 87

microcytic, hypochromic cells with poikilocytosis present

Front 88

What is a characteristic finding in the iron deficiency anemia?

Back 88

low ferritin, low iron, high TIBC, high transferrin

Front 89

Which red blood cell shows a peripheral rim of hemoglobin with a dark staining central area?

Back 89

leftocyte

Front 90

Target cells are present in what conditions?

Back 90

thalassemia

myelofibrosis

postsplenectomy

Front 91

Basophilic stippling refers to what?

Back 91

aggregated RNA in the red blood cells

Front 92

Which red cell blood inclusion is described as a threadlike oval or figure-eight-shaped?

Back 92

Cabot rings

Front 93

What inclusion represents a remnant of nuclear DNA in a red blood cell?

Back 93

Howell-Jolly body

Front 94

RNA remnants in red blood cells are visualized by which supravital stain?

Back 94

new methylene blue

Front 95

What are red blood cells that contain iron-stained granules termed?

Back 95

siderocytes

Front 96

Chronic blood loss can lead to what kind of anemia?

Back 96

iron deficiency anemia

Front 97

Increased iron in the mitochondria of normoblasts is characteristic of which type of anemia?

Back 97

sideroblastic anemia

Front 98

A peripheral blood smear from a patient with thalassemia would exhibit what?

Back 98

target cells, basophilic stippling, teardrop cells

Front 99

What lab results are found in iron deficiency anemia but not in thalassemia?

Back 99

low serum iron and increased total iron binding capacity

Front 100

A macrocytic anemia characteristically accompanies what?

Back 100

fish tapeworm infection

vitamin B12 deficiency

folate deficiency

Front 101

What is NOT typically seen in the peripheral smear in megaloblastic anemia?

Back 101

spherocytes

Front 102

What is the most characteristic change seen in the white blood cells of the megaloblastic anemia bone marrow?

Back 102

giant metamyelocytes

Front 103

What is true of hereditary elliptocytosis?

Back 103

osmotic fragility and autohemolysis are usually normal

Front 104

an increased osmotic fragility is observed in which type of hemolytic anemia?

Back 104

hereditary spherocytosis

Front 105

What test is associated with the diagnosis of paroxysmal nocturnal hemoglobinuria?

Back 105

sugar water test

sucrose hemolysis

acidified serum test

Front 106

What is the most common thalassemia in the United States?

Back 106

beta thalassemia minor