Exam III

Question 1

How is the promyelocyte differentiated from the myeloblast?

Answer 1

promyelocytes have azurophilic primary granules

Question 2

At what stage does differentiation of the granules of the cells of the myelocytic series take place?

Answer 2

myelocyte

Question 3

How is the metamyelocyte differentiated from the myelocyte?

Answer 3

shape of the nucleus; metamyelocytes have kidney bean-shaped nuclei while myelocytes have round ones

Question 4

How is the band differentiated from the metamyelocyte?

Answer 4

shape of the nucleus; bands are horseshoe-shaped with uniform thickness

Question 5

What cell contains granules that retain the acid portion of Wright’s stain?

Answer 5

eosinophils (acid stain = eosin)

Question 6

What substances are produced by eosinophils?

Answer 6

anti-histamine

Question 7

What cell contains granules that are not uniform in shape, stain with the basic portion of Wright’s stain, and may cover the nucleus?

Answer 7

basophils

Question 8

What are mast cells?

Answer 8

tissue basophils

Question 9

Where do B-cells originate?

Answer 9

bone marrow

Question 10

Where do T-cells originate?

Answer 10

thymus

Question 11

How can B-cells and T-cells be differentiated?

Answer 11

through surface markers (surface immunoglobulins)

Question 12

What type of lymphocyte are most of the circulating lymphocytes and what is their appearance?

Answer 12

T-cells; small, mature lymphs with clumping nuclei and not much cytoplasm

Question 13

During blastic transformation, B-cells become what?

Answer 13

plasma cells

Question 14

What cell has an eccentric nucleus with clumped chromatin, basophilic cytoplasm, and a clear perinuclear halo (hof)?

Answer 14

plasma cell

Question 15

Where are plasma cells normally found?

Answer 15

bone marrow

Question 16

What cellular organelle is associated with the hof?

Answer 16

Golgi apparatus

Question 17

Monocytes circulate in the peripheral blood but are known as _______ or _______ in the tissues.

Answer 17

macrophages; histiocytes

Question 18

Where do monocytes originate?

Answer 18

bone marrow

Question 19

How would you describe a monocyte according to the following: appearance of chromatin, shape of nucleus, color of cytoplasm, presence of pseudopodia or vacuoles?

Answer 19

folded, irregular shape; lobulated nucleus; slate grey cytoplasm; vacuoles present

Question 20

What is the function of monocytes?

Answer 20

phagocytosis

Question 21

Name several characteristics that can be observed in the neutrophils during inflammation, infection, or other toxic states and describe their appearance.

Answer 21

Dohle bodies (RNA), toxic granules (blue-black granules in cytoplasm), toxic vacuoles (holes in cytoplasm)

Question 22

What are Russell bodies?

Answer 22

aggregates of immunoglobulin that stain red

Question 23

Describe Alder-Reilly.

Answer 23

abnormal azurophilic granulation

Question 24

Describe May-Hegglin.

Answer 24

weird platelets, Dohle-like inclusions, blue staining

Question 25

Describe Pelger-Huet.

Answer 25

dumb-bell shaped hyposegmentation of neutrophils

Question 26

What is the normal WBC count?

Answer 26

5-10 thousand

Question 27

If blood is drawn to the 0.5 mark and diluent to the 11 in a WBC pipette, what is the resulting dilution?

Answer 27

standard WBC count (1:20 dilution)

Question 28

Given the number of cells counted on both sides of the hemocytometer, how could you determine the WBC count on the performance of a standard WBC count?

Answer 28

average of both counts x 50

Question 29

What effect does hemolysis have on a WBC count?

Answer 29

none

Question 30

Name several sources of error in the performance of a manual WBC count.

Answer 30

too much blood/diluent, overfilling/underfilling, cracked or dirty hemocytometer, edema

Question 31

How does the normal WBC count vary during the day?

Answer 31

WBCs hang on the wall at night and fall off with activity during the day, so counts will be higher during the day and lower at night

Question 32

What explanation is given for the variation of WBC counts?

Answer 32

margination

Question 33

What is the normal eosinophil count?

Answer 33

77-440

Question 34

What can cause an increased or decreased eosiniphil count?

Answer 34

increased - hypoadrenalism, allergies, parasitic infection, skin disorders, blood diseases; decreased - anemia, hyperadrenalism (Cushing's disease), infectious mononucleosis, pernicious anemia, aplastic anemia

Question 35

To compensate for the normally low number of eosinophils, what adjustment in the procedure is made when doing manual eosinophil counts?

Answer 35

increase the number of fields observed, and/or increase the volume (over entire hemocytometer)

Question 36

Name two other hemocytometers that can be used for eosinophils and basophil counts.

Answer 36

Speirs-Levy and Fuchs-Rosenthal

Question 37

Name several factors that can result in an excessively pink Wright's stained smear.

Answer 37

too acidic - overwashed or understained

Question 38

Name several factors that can result in an excessively blue Wright's stained smear.

Answer 38

too alkaline - underwashed or overstained

Question 39

What three things are always performed when doing a differential count, and why?

Answer 39

comment on RBC morphology, count and classify 100 cells, perform a platelet count estimation; used for diagnosis, monitor therapy, or to get a picture of overall health

Question 40

What is the most common type of WBC in a normal smear?

Answer 40

segmented neutrophil

Question 41

What is the least common type of WBC in a normal smear?

Answer 41

basophils

Question 42

What is the most common type of WBC in a child's smear?

Answer 42

lymphocytes

Question 43

What is a "shift to the left" and in what conditions is it likely to occur?

Answer 43

an increase in young cells (i.e., increase in bands); occurs in CML infection, leukemias, and bacterial infections

Question 44

What is the largest WBC in a normal peripheral blood smear?

Answer 44

monocyte

Question 45

Which cells are classified as NRBCs on a peripheral blood smear?

Answer 45

blast cells, prorubricytes, rubricytes, metarubricytes

Question 46

If large numbers of NRBCs are observed on a peripheral blood smear, what effect will this have on the WBC count?

Answer 46

they are counted as WBCs; this will increase the WBC count (may falsely increase the white count)

Question 47

How can you correct your count for NRBCs?

Answer 47

(WBC x 100) / (100+NRBCs)

Question 48

Where are platelets produced?

Answer 48

bone marrow

Question 49

What is the largest blood cell normally produced by the body?

Answer 49

megakaryocyte

Question 50

What is endomitotic division?

Answer 50

nucleus divides, cytoplasm enlarges; results in a multi-nucleated cell

Question 51

What is the normal platelet count?

Answer 51

varies greatly, but for testing purposes: 150,000-450,000

Question 52

What method employs the phase contrast microscope in counting platelets?

Answer 52

Brecker Cronkite

Question 53

How is a manual platelet count calculated using the Unopette method?

Answer 53

count entire center square; number of cells x 1000

Question 54

What criteria are used to estimate platelets in a peripheral blood smear?

Answer 54

estimates are routinely performed using 100x oil immersion in an area of the smear where the RBCs are barely touching; rough estimates can be determined by the number of platelets per field; anywhere between 7-22 platelets per field is considered normal

Question 55

Describe Auer rods.

Answer 55

reddish-purple blast inclusion

Question 56

Describe Dohle bodies.

Answer 56

pale blue remnants of RNA

Question 57

Describe Pelger-Huet.

Answer 57

decreased segmentation of neutrophils

Question 58

Describe toxic granulation.

Answer 58

dark blue-black cytoplasm granules

Question 59

Describe Alder-Reilly.

Answer 59

azurophilic granulation of all white cells