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Flashcards in Exam 3 Deck (58)
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1
Q

How is the promyelocyte differentiated from the myeloblast?

A

Promyelocyte has azurophilic (primary) granules

2
Q

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

A

myelocyte

3
Q

How is the metamyelocyte differentiated from the myelocyte?

A

Shape of nucleus:
Meta => kidney bean shaped
Myelo => round

4
Q

How is the band differentiated from the metamyelocyte?

A

Shape of nucleus:

Band => horse shoe shaped (uniform thickness)

5
Q

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

A

eosinophil (acid stain = eosin)

6
Q

What substances are produced by eosinophils?

A

anti-histamine

basophils produce histamine

7
Q

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

A

basophils

8
Q

What are mast cells?

A

tissue basophils

9
Q

Where do B cells originate?

A

bone marrow

10
Q

Where do T cells originate?

A

thymus

11
Q

How can B cells and T cells be differentiated?

A

through surface markers (surface immunoglobulins)

12
Q

What type of lymphocyte (B cell or T cell) are most of the circulating lymphocytes and what is their appearance?

A

T-cell. Small, mature lymphs; clumping nucleus, not much cytoplasm

13
Q

During blastic transformation, B cells become what?

A

plasma cells

14
Q

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

A

plasma cell

15
Q

Where are plasma cells normally found?

A

bone marrow

16
Q

What cellular organelle is associated with the hof?

A

Golgi apparatus

17
Q

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

A

macrophages or histiocytes

18
Q

Where do monocytes originate?

A

bone marrow

19
Q

What is the function of the monocyte?

A

phagocytosis

20
Q

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

A

Dohle bodies: RNA
toxic granules: blue/black granules in cytoplasm
toxic vacuoles: holes in cytoplasm

21
Q

What are Russell bodies?

A

aggregates of immunoglobulin that stain red

22
Q

Describe Alder-Reilly.

A

abnormal azurophilic granulation

23
Q

Describe May-Hegglin.

A

Weird platelets, Dohle-like inclusions, blue staining

24
Q

Describe Pelger-Huet.

A

dumbbell shaped hyposegmentation of neutrophils

25
Q

What is the normal WBC count?

A

5-10 thousand

26
Q

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

A

standard WBC count, 1:20 dilution

27
Q

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?

A

average of both counts x 50

Ex: 120100/2 is the same as 11050

28
Q

What effect does hemolysis have on a WBC count?

A

none

29
Q

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

A
too much blood/diluent
overfill/underfill hemocytometer
cracks
edema
dirty hemocytometer
30
Q

How does the normal WBC count vary during the day?

A

WBC’s hang on wall at night and fall off with activity during the day. higher during day lower at night

31
Q

What explanation is given for the variation of WBC counts?

A

margination

32
Q

What is the normal eosinophil count?

A

77-440

33
Q

What can cause an increased or decreased eosinophil count?

A

Increased: hypoadrenalism; allergies;parasitic infections; skin disorders; blood diseases
Decreased: anemia; hyperadrenalism (Cushings disease);IM; Pern. anemia; aplastic anemia

34
Q

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

A
increase # fields
increase volume (entire hemocytometer)
35
Q

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

A

Speirs-Levy

Fuchs-Rosenthal

36
Q

Name several factors that can results in an excessively pink Wright’s stained smear.

A

too acidic- overwashed or understained

37
Q

Name several factors that can result in an excessively blue Wright’s stain smear.

A

too alkaline- underwashed or overstained

38
Q

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

Why?

A

RBC morphology
count and classify 100 cells
platelet count estimation

Used for: Dx disease, monitor therapy, or to get picture of overall health.

39
Q

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

A

segmented neutrophils

40
Q

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

A

basophils

41
Q

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

A

lymphocytes

42
Q

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

A

increase in young cells (increase in bands)

occurs in CML (infection); leukemias; bacterial infections

43
Q

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

A

Monocyte

44
Q

Which cells are classified as NRBCs on a PBS?

A

blast cells, prorubricytes, rubricytes, metarubricytes

45
Q

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

A

they are counted as WBCs, this will increase the WBC count

may falsely increase the white count

46
Q

How can you correct your count for NRBCs?

A

(WBC x 100)/(100+NRBCs)

47
Q

Where are platelets produced?

A

Bone marrow

48
Q

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

A

Megakaryocyte

49
Q

What is endomitotic division?

A

POSSIBLE BONUS QUESTION

Nucleus divides, cytoplasm just enlarges. Multinucleated cell.

50
Q

What is the normal platelet count?

A

Varies greatly. For this test:

150,000-450,000/mm3

51
Q

What method employs the phase contrast microscope in counting platelets?

A

Brecker Cronkite

52
Q

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

A

Entire center square = 0.1 mm^3

1: 100 dilution
0. 1/100 = 1000

So: # cells * 1000

53
Q

What criteria are used to estimate platelets in a PBS?

A

PLT estimates are routinely performed using a 100X oil objective in an area of the smear where the red blood cells (RBCs) barely touch. A rough estimate can be determined by the number of platelets per 100X oil-immersion field (OIF). References state that anywhere from 7 to 22 platelets per OIF correlates with a normal platelet count.

54
Q

Reddish-purple in blast inclusion

A

Auer rod

55
Q

Pale blue remnants of RNA

A

Dohle bodies

56
Q

Decreased segmentation of neutrophils

A

Pelger-Huet

57
Q

Dark blueish black cytoplasm granules

A

Toxic granulation

58
Q

Azurophilic granulation of all white cells

A

Alder-Reilly