BSNC 3000 Module 8 - Clotting and Hemostasis and
DVT questions with verified answers
Clotting Ans✔✔-- a physiological process in response to vascular injury
in which platelets and fibrin form a clot to stop bleeding
Scope of clotting Ans✔✔-- excessive clotting
- local/systemic
- thrombosis
- bleeding
- local/systemic
- inefficient clotting (bleeding)
Requirements for effective clotting Ans✔✔-- platelets
- clotting factors (liver function)
- calcium
- vitamin K
Hemostasis Ans✔✔-- the arrest of bleeding
- requires a balance between clot formation and clot prevention
Clot formation
- coagulation
,- platelets
- endothelium
Clot prevention
- fibrolysis
- anti-coagulation
Steps of hemostasis (8) Ans✔✔-- platelet adhesion and activation
- platelet secretion and aggregation
- thromboxane synthesis
- activation of the extrinsic coagulation pathway
- activation of the intrinsic coagulation pathway
- activation of the common coagulation pathway
- regulation of clotting by endogenous anticoagulants
- clot breakdown by the fibrinolytic system
Vasoconstriction Ans✔✔-- normally blood flows in concentric layers
(laminar flow) with a central layer of blood cells and plasma following
closer to the endothelial surface
- blood vessel wall injury and vasoconstriction cause a disturbance in
laminar flow
- this allows platelets to contact the blood vessel wall
, Platelet adhesion and activation (Step 1 - platelet plug) Ans✔✔--
platelets adhere to subendothelial collagen that is exposed due to
vascular injury
- damaged endothelial cells release von Willebrand factor (vWF) which
bridges the binding of platelets to collagen
- the adhesion of platelets to collagen stimulates platelet activation
- activated platelets change shape and form processes that extend
towards other platelets
Platelet aggregation and secretion (Step 2 - platelet plug) Ans✔✔--
platelet activation causes a change in shape of fibrinogen receptors
exposing the binding site for fibrinogen
- fibrinogen bridges the binding of adjacent platelets, allowing platelets
to aggregate
- activated platelets secrete substances stored in granules including vWF,
fibrinogen, calcium, and ADP
Substances secreted by activated platelets Ans✔✔-- fibrinogen (bridges
the binding of neighbouring platelets for aggregation)
DVT questions with verified answers
Clotting Ans✔✔-- a physiological process in response to vascular injury
in which platelets and fibrin form a clot to stop bleeding
Scope of clotting Ans✔✔-- excessive clotting
- local/systemic
- thrombosis
- bleeding
- local/systemic
- inefficient clotting (bleeding)
Requirements for effective clotting Ans✔✔-- platelets
- clotting factors (liver function)
- calcium
- vitamin K
Hemostasis Ans✔✔-- the arrest of bleeding
- requires a balance between clot formation and clot prevention
Clot formation
- coagulation
,- platelets
- endothelium
Clot prevention
- fibrolysis
- anti-coagulation
Steps of hemostasis (8) Ans✔✔-- platelet adhesion and activation
- platelet secretion and aggregation
- thromboxane synthesis
- activation of the extrinsic coagulation pathway
- activation of the intrinsic coagulation pathway
- activation of the common coagulation pathway
- regulation of clotting by endogenous anticoagulants
- clot breakdown by the fibrinolytic system
Vasoconstriction Ans✔✔-- normally blood flows in concentric layers
(laminar flow) with a central layer of blood cells and plasma following
closer to the endothelial surface
- blood vessel wall injury and vasoconstriction cause a disturbance in
laminar flow
- this allows platelets to contact the blood vessel wall
, Platelet adhesion and activation (Step 1 - platelet plug) Ans✔✔--
platelets adhere to subendothelial collagen that is exposed due to
vascular injury
- damaged endothelial cells release von Willebrand factor (vWF) which
bridges the binding of platelets to collagen
- the adhesion of platelets to collagen stimulates platelet activation
- activated platelets change shape and form processes that extend
towards other platelets
Platelet aggregation and secretion (Step 2 - platelet plug) Ans✔✔--
platelet activation causes a change in shape of fibrinogen receptors
exposing the binding site for fibrinogen
- fibrinogen bridges the binding of adjacent platelets, allowing platelets
to aggregate
- activated platelets secrete substances stored in granules including vWF,
fibrinogen, calcium, and ADP
Substances secreted by activated platelets Ans✔✔-- fibrinogen (bridges
the binding of neighbouring platelets for aggregation)
