FINALS 1.2: PLATELETS Flashcards
(67 cards)
1
Q
other term for platelets
A
thrombocytes
2
Q
hormone in plt production
A
thrombopoietin
3
Q
t/f: plts have metabolically inactive cell fragments
A
false
4
Q
reference range of plts
A
150-450x10^9/L
5
Q
receptor of thrombocytes
A
mpl
6
Q
life span of plts
A
8-9 days
7
Q
how many plts in a field of oil immersion field
A
7-21 platelets
8
Q
size of a platelet
A
2-4uL or 6.8-10.2fL
9
Q
anticoagulant used?
it can cause what?
corrected by what anticoagulant?
A
edta
platelet satellitism
sodium citrate
10
Q
multiply platelets by
A
1.1
11
Q
cells that causes pseudothrombocytopenia
A
platelet satellitism
giant platelets
12
Q
what anomaly is present if there is a giant platelet
A
may hegglin anomaly
12
Q
- preserve the endothelial lining of blood vessels - forming platelet plug
- participates during plasma coagulation
a. primary
b. secondary
A
- primary
- secondary
13
Q
primary factor of coagulation
A
tissue factor
14
Q
act as a mesh, to stabilize the entire clot that formed
A
fibrin polymer
15
Q
megakaryocytes has how many somatic cells? meaning it is a?
A
64 - polyploidy
16
Q
megakaryocytes undergo what form of mitosis
A
endomitosis
17
Q
- platelets found in the spleen
- immediately available in times of demand
A
sequestered platelets
18
Q
- aka stress platelets
- carry free ribosomes and fragments of rough endoplasmic reticulum
A
reticulated platelets
19
Q
diameter of reticulated platelets
A
> 6um
19
Q
clinical use of reticulated plts
A
it can help differentiate bone marrow failure from peripheral destruction in thrombocytopenia
20
Q
major regulator if plt production
A
thrombopoietin
21
Q
thrombopoietin is produced by the
A
liver
22
Q
biggest cell in the bone marrow
A
megakaryocyte
23
- later stage process, dna replication w/o cell division
endomitosis
24
megakaryocyte came from what progenitor
common myeloid progenitor
24
differentiation of megakaryocyte and cmp
influenced by GATA1 and myp
24
what transcription factor is important for endomitosis
runx1
25
differentiate GATA1 and MYP
GATA1 PROMOTES differentiation, while MYP INHIBITS differentiation
26
- mk-1 stage
- cannot be reliably distinguished from myeloblast or pronormoblast
- begins to develop MOST of its cytoplasmic ultrastructure
megakaryoblast
27
to distinguish megakaryoblast you must to what
flow cytometry using cd markers
28
- mk - ii stage
- nuclear lobularity
- fully ploidy by the end of this stage
promegakaryocyte
29
- mk - iii stage
- easily recognized at 10x magnification (30-50um)
- azurophilic cytoplasm
- at full maturation, plt shedding process
megakaryocytes
30
DMS stands for
demarcation membrane system
31
each megakaryocyte can shed how many plts
2000-4000
32
function and role:
- peripheral zone
- structural zone
- organelle zone
- membrane systems
- adhesion and aggregation
- structure and support
- storage and secretion
- storage and secretion
33
- sugary layer that is thicker than other cells
- responsible for the plts surface negative charge
glycocalyx
34
- phospholipid bilayer
- predominantly phospholipids
plasma membrane
35
neutral phospholipids
phosphatidylcholine
sphyngomyelin
35
charged phospholipids
phosphatidylinositol
phosphatidylethanolamine
phosphatidylserine
35
phospholipid that is important in the production of arachidonic acid
phosphatidylinositol
36
actively involved in platelet function
plasma membrane receptors
36
- receptor for von willebrand factor
- platelet adhesion
GP Ib, IX, V
37
- integrin aIIbB3
- receptor for fibrinogen
- platelet aggregation
GP IIb, IIIa
38
- provides overall structural support of the plasma membrane
- stabilizes plts resting discoid shape
- provide a means of shape change when plt is activated
cytoskeleton
39
interact together to maintain the shape of plt
microtubule
microfilaments
39
- largest cytoskeletal filament
- stabilizes the discoid shape of the resting platelet
- disassembles at cold temperature and returns to original disc shape at 37degrees celsius
microtubules
40
anchors plasma membrane glycoproteins and proteoglycans
microfilaments with actin
40
- desmin, vimentin
- connects with actin and tubules to maintain platelet shape
intermediate filaments
41
important in the function of plts
dense granules
a-granules
42
- stains black (opaque) with osmium - dye
- high calcium content
- 2-7 per platelet
- released directly into plasma
dense granules
43
dense granules content
adp
atp
serotonin
calcium and magnesium
44
- aka light granules
- most numerous (50-80 per platelet)
- stains medium gray in osmium-dye
- fuses with surface-connected canalicular system for release of granule contents
alpha granules
45
- secretes lysosomal enzymes when activated
- hydrolytic enzymes
lysosomes and peroxisomes
46
peroxisomes are involved in what metabolism
lipid metabolism
47
- originates as invagination of the plasma membrane
- allows platelets to store additional hemostatic proteins
- provides passage for entry of external substances and release of granule content
- provides membrane during platelet activation
surface-connected canalicular system
48
- sequestration of calcium necessary for platelet activation
- bears phospholipase a2, cyclooxygenase, and thromboxane a2 synthetase
- MAJOR SITE IF THROMBOXANE A2 AND PROSTAGLANDINS
dense tubular system
49
serves as a glue between plts and blood vessel wall
von willebrand factor
50
what gp makes collagen
GP Ia, IIa, GP VI
51
changes in metabolic biochemistry and morphology of platelets
plt activation
51
plts sticking to endothelium foloowing tissue injury
plt adhesion
52
end product of plt activation
GP IIb, IIIa - receptor for fibrinogen
53
stimulus that promote in the sense of activation and aggregation
agonists
54
- platelet release action
- energy dependent
- release is through surface- connected canalicular system
platelet secretion
54
test the extent of plt aggregation in the presence of agonists, induces platelets
platelet aggregometry
54
- reorganization of microtubules and cytoskeletal proteins
- brings platelet granules in closer proximity to surface-connected canalicular system
platelet shape change
55
- platelets binding to other platelets
- neighboring platelets participate as mediated by agonists like TxA2 and ADP
platelet aggregation
