Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

HEMA 256 > Module 3_Mechanisms of Normal Hemostasis > Flashcards

Module 3_Mechanisms of Normal Hemostasis Flashcards

1
Q

hemostasis

A

prevention and arrest of bleeding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

vascular component

A

blood vessels and surround ing sub-endothelium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what are the 5 major components in hemostasis?

A

vascular, platelet, plasma components (coagulation system, fibrinolytic system, natural anticoagulants & inhibitors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what are firstly exposed during injury?

A

platelets and plasma components to the sub endothelial tissues (collagen and III - tissue thromboplastin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is the sequence of hemostatic plug formation following the injury?

A
  1. release of activator
  2. blood exposed to sub endothelium
  3. vasoconstriction
  4. platelet adhesion to subendo
  5. platelet aggreg - temp plug
  6. extrinsic coagulation -fibrin formation - 2ndry platelet aggress which is permanent
  7. intrinsic coagulation - fibrin formation
  8. platelet retraction - hemostatic plug
  9. fibrinolysis and action of natural anticoagulants
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is vascular potency?

A

keep blood cells from leaking out of circulation while allowing diapedesis of mobile cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are the 2 functions of vasoconstriction in injury?

A
  1. reduce blood flow

2. promoting platelet adhesion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what are the two types of vasoconstriction?

A
  1. muscular: immediate
  2. humoral: delayed. release of vasoconstrictor substances that activate platelets and nearby intact endothelial cells to release endothelin. Endothelin induces SM contraction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is tissue thromboplastin and its function?

A

III, lipoprotein released from injury cell.

activates VII in extrinsic pathway.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is plasminogen activator (tPA) and its function?

A

activates the fibrinolytic system.

some released by injury, more release after healing. dissolve the clot.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what happen when collagen in contact with plasma?

A
  1. adhesion of blood platelets to subendothelium

2. activation XII of intrinsic pathway

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

In thrombopoiesis, what are the two unique factors of megakaryocytes differ from RBC production?

A
  1. get larger as they mature

2. no cellular division. but has endomitosis (repeated nuclear divisions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what and where is platelet made from?

A

cytoplasmic fragment of the megakaryocyte. In bone marrow and lifespan 8~10 days in circulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

T or F: 20% of the platelet may be larger than normal (megathrombocytes)

A

T

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what are the three zones of platelet?

A

peripheral zone, sol-gel zone, organelle zone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is peripheral zone and its function?

A

in the plasma membrane, has peripheral proteins - glycocalys

function: adhesion and aggregation of platelets

17
Q

what is sol-gel zone and its function?

A

just below PM, has microtubules and microfilaments, contractile proteins (thrombosthenin and actomyosin).

function: platelet retraction and shape changes (viscous metamorphosis during secondary aggregation)

18
Q

what is organelle zone?

A

It is the cytoplasm and its components: granules, mitochondria, dense tubular system, canicular system.

19
Q

what is canicular system and its function?

A

an extensive canal system from in and out

Function: It carries granular contents to surface

20
Q

what is dense body?

A

2~10 in each platelet, rich in serotonin, vasoactive catecholamines (nor-epi and DOP), nucleotides (AMP, ADP, ATP), Ca2+, pyrophosphate

21
Q

what is alpha (translucent) granule?

A

20~200/platelet.
contains: III, Fibrinogen, thrombospondin (promotes plate aggreg), PF-IV

…… and unimportantly, B-thromboglogulin (antiheparin), platelet drived growth factor (PDGF that induces new tissues growth), coag factors XIII, V, VWF, albumin, alpha2-antiplasmin (inhibits fibrinolysis).

22
Q

T/F: 70% platelets are circulating, 30% sequestered

A

T

23
Q

T/F: in the 30% sequestered platelet distribution, 17% in splenic sinusoid and 13% in microcirculation and sinusoids of the liver, lungs and bone marrow.

A

T

24
Q

What is platelet factor and its function?

A

substance that is absorbed onto platelet membrane or carried in the platelet granule. It is released during release rxn and influence hemostasis

25
Q

what is PF-1 and its function?

A

absorbed coagulation factor V

participate in coagulation rxn on the surface of the platelet

26
Q

what is PF-2 and its function?

A

fibrinogen activating factor.

renders fibrinogen more sensitive to thrombin

27
Q

what is PF-3 and its function?!!?

A

platelet phospholipid

accelerate coagulation by activating X and prothrombin. Acts as organizational surface to bring required factors in close proximity

28
Q

what is PF-4 and its function?

A

anti-heparin factor, a glycoprotein, found in endothelial cells

inhibits heparin so less clot formation

HEMA 256 (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions