exam 3 Flashcards
how is the promyelocyte differentiated from the myeloblast?
promyelocyte has azurophilic (primary) granules
at what stage does differentiation of the granules of the cells of myelocytic series take place?
myelocyte
how is the metamyelocyte differentiated from the myelocyte?
shape of the nucleus :
meta - kidney bean
myelo - round
how is the band differentiated from the metamyelocyte?
shape of nucleus :
band- horse shoe shaped (uniform thickness)
what cell contains granules that retain the acid portion of the Wright’s stain?
eosinophil
what substances are produced by eosinophils?
anti-histamine (basophils produce histamine)
what cell contains granules that are not uniform in shape, stain with the basic portion of Wright’s stain, and which may cover the nucleus?
basophils
what are mast cells?
tissue basophils
where do B cells originate?
bone marrow
where do T cells originate?
Thymus
how can the two ( B cells and T cells) be distinguished?
through surface markers
what type of lymphocyte (B or T cell) are most of the circulating lymphocytes and what is their appearance?
T-cell. Small, mature lymphs, clumping nucleus, not much cytoplasm
During blastic transformation, B cells become
plasma cells
what cell has as eccentric nucleus with clumped chromatin, basophilic cytoplasm, and a clear perinuclear halo (hof)?
plasma cell
where are plasma cells normally found
bone marrow
what cellular organelle is associated with the hof?
Golgi apparatus
monocytes circulate in the peripheral blood but are known as ____ or ____ in the tissues
macrophages
histiocytes
where do monos originate?
bone marrow
how would you describe a monocyte according to the following: appearance of chromatin, shape of the nucleus, color of cytoplasm, presence of pseudopodia or vacuoles?
Folded irregular nucleus
Slate gray cytoplasm
Has vacuoles
what is the function of the monocyte?
phagocytosis
name several characteristics that can be observed in neutrophils during inflammation, infection, or other toxic states and describe their appearance.
dohle bodies: RNA
toxic granules: blue/black granules in cytoplasm
toxic vacuoles: holes in cytoplasm
what are Russell bodies?
aggregates of immunoglobulin that stain red
Would not be found in neutrophils
alder-Reilly
abnormal azurophilic granulation
May-Hegglin
weird platelets dohle-like inclusions, blue staining
Pelger-Huet
dumbbell shaped hyposegmentation of neutrophils
what is the normal WBC count
5-10 thousand
if blood is drawn to the 0.5 mark and diluent to the 11 in a white blood cell pipette, what is the resulting dilution?
standard WBC count, 1:20 dilution
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?
average of both counts X 50 ( ex: 120100/2 is the same as 11050)
what effect does hemolysis have on a WBC count?
none
name several sources of error in the performance of a manual WBC count.
too much blood/diluent overfill/ underfill hemocytometer
how does the normal WBC count vary during the day?
higher in evening ; lower in the morning
What explanation is given for the variation of WBC count during the day?
margination
what is the normal eosinophil count?
77-440
what can cause an increased or decreased eosinophil count?
increased: hypoadrenalism, allergic disease, parasitic infection, skin disease
decreased: anemia, hyperadrenalism
to compensate for the normally low number of eosinophils, what adjustment in the procredure is made when doing a manual eo count?
increase # of fields increase volume (entire hemocytometer)
name two other hemocytometers that can be used for eosinophil and basophil counts.
speirs-levy
fuchs-rosenthal
name several factors that can results in an excessively pink Wright’s stained smear
too acidic- overwashed of understained
name several factors that can results in an excessively blue smear?
too alkaline- underwashed, overstained
what three things are always performed when doing a differential count?
RBC morphology
100 WBC count
platelet count/ estimation
what is the most common type of WBC in a normal smear?
segmented neutrophil
why are the normal things that are performed in a differential count performed?
Dx disease
monitor therapy
get overall pic of health
what is the least common type of WBC in a diff count
basophils
what is the most common WBC in a diff count in a child?
lymphocytes
what is a “shift to the left” and in what conditions is it likely to occur?
increase in young neutrophil cells (bands) occurs in CML inflammation or pregnancy
what is the largest WBC in a normal peripheral blood smear?
monocyte
which cells are classified as NRBCs on a PBS
blast cells, prorubricytes, rubricytes, metarubricytes
if large numbers of NRBCs are observed on a PBS, what effect will this have on the WBC count?
the are counted as WBC will increase the WBC count (falsely high)
how can you correct for large numbers of NRBCs observed on a PBS
(WBC X 100) / (100+NRBC)
where are platelets produced?
bone marrow
what is the largest blood cell normally produced by the body?
megakarycoyte
what is endomiotic division?
nucleus divides, cytoplasm enlarges nultinucleated cell
what is the normal platelet count?
varies greatly 150,000-450,000/mm3
what method employs the phase contrast microscope in counting platelets?
brecker cronkite
how is a manual platelet count calculated using the Unopette method?
entire center
1:100 dilution
what criteria are used to estimate platelets in a PBS?
performed w/ 100 X oil in feather, rough estimate = # platelets per oif 7-22 PLATELETS PER oIF correlates with normal platelet count
