NUR 339- Exam 4 Test Questions and
Already Passed Answers Graded A+
2025-2026 Updated.
What may clot disorders be due to? - Answer -Issue with platelets or coagulation factors
-Hyper or hypo coagulability
How long do platelets live in circulation? - Answer 8-9 days
Where are many platelets stored? - Answer Spleen
When are platelets released? - Answer When needed
What is the function of platelets? - Answer To form platelet plug to increase clotting
What do the platelet granules release? - Answer Mediators
How many platelets are usually in the blood? - Answer 150,000-400,000/mL
Are platelets thrombocytes? - Answer Yes
Where are megakaryocytes formed and what do they do? - Answer Formed in the bone
marrow and break apart to form many platelets.
What does thrombopoietin control? - Answer Controls platelet production
Where is thrombopoietin made? - Answer In the liver, kidney, smooth muscle, and bone
marrow
What is the 1st stage of normal clotting and how long does it take to occur? - Answer -Vessel
spasm.
-Transient (< 1 min)
,What is the vessel spasm due to? - Answer Hormonal (thrombaxane A2) and neural control
What is the 2nd stage of clotting and how long does it take for it to occur? - Answer -
Formation of platelet plug
-Occurs within seconds
How does a platelet plug form? - Answer 1. Damaged vessel leaves collagen exposed
2. Von Willebrand factor is released by endothelial wall and attracts and activates platelets
3. Platelets "activated" and receptors bind to Von Willebrand factor and adhere to exposed
collagen
4. Chemical mediators released by platelets cause more platelet aggregation and clumping: ADP,
thromboxane A2 (a prostaglandin), thrombin causing nearby platelets to get sticky and clump
together
5. Activated platelets change shape and release chemical mediators causing more platelet
aggregation
6. Forms a loose platelet plug and activates the clotting cascade
What is the 3rd stage of clotting? - Answer Blood coagulation
What is blood coagulation? - Answer Process by which fibrinogen converted to fibrin, which
forms meshwork that holds blood cells together in clot which stabilizes clot
What happens during blood coagulation? - Answer -Coagulation factors become activated on
platelet surface and initiate clotting cascade:
^2 pathways (intrinsic and extrinsic) both end with activation of Factor X leading to conversion
of prothrombin to thrombin that converts fibrinogen to fibrin causing fibrin strands trap rbcs &
stabilizes clot
Where is the intrinsic pathway? - Answer Occurs in vascular system and is slow
Where is the extrinsic pathway? - Answer Occurs in tissues and is fast
Where do the intrinsic and extrinsic pathways converge? - Answer Factor 10
,What do procoagulation factors promote? - Answer Clotting
What procoagulation factor is needed in almost all steps of clotting? - Answer Calcium (factor
5)
What would the effect of hypocalcemia be on clotting? - Answer Hypocoagulation
What do anticoagulation factors do? - Answer Inhibit clotting
What are the natural anticoagulants? - Answer -Antithrombin III - neutralizes thrombin
-Protein C - inhibits thrombin
-Protein S - enhances action of Protein C
-Heparin - contained in granules in basophils
What happens when there are deficiency states of the natural anticoagulants? - Answer
Hypercoagulability
What is the 4th step of clotting? - Answer Clot retraction-contraction
What occurs during clot retraction-contraction? - Answer Platelets contract and squeeze
serum out of clot and pull vessel edges together causing shrinkage of clot
What is the 5th stage of clotting? - Answer Clot dissolution (fibrinolysis).
What does the clot start to do shortly after clot formation? - Answer Dissolve
What happens during fibrinolysis? - Answer Sequence of steps with activators and inhibitors
leading to formation of plasmin (enzyme) which lyses clots
Where does plasminogen circulate? - Answer In the blood
What activates plasminogen to plasmin and what happens because of it? - Answer Activated
to plasmin by tissue plasminogen activator (tPA) and urokinase-type plasminogen activator >
, What state are activators and inhibitors in a state of? - Answer Balance and both synthesized
by the liver and vascular endothelial lining
What does the breakdown of fibrin lead to? - Answer Production of fibrin degradation
products (can be measured in serum as indicator of fibrinolysis)
What are the hypercoagulable conditions due to? - Answer -Increased platelet function
-Increased activity of coagulation system
What would cause increased platelet function? - Answer Due to disturbance in blood flow,
endothelial damage or increased sensitivity of platelets to clotting factors
What diseases is increased platelet function seen? - Answer -Atherosclerosis
-Hypertension
-Cancers
-Thrombocytosis
What is thrombocytosis? - Answer 1 million platelets or more
What can cause increased activity of the coagulation system? - Answer -Hereditary conditions:
inherited defects in Factor V or prothrombin gene > increased incidence of recurrent DVTs/clots
-Stasis of blood flow: causes accumulation of platelets and activated clotting factors and is seen
with immobility, heart failure
-Activation of coagulation factors: high levels of estrogen, cancer, sepsis
What can result from increased activity of coagulation system? - Answer DVT, PE, MI, CVA,
PVD
Who is at risk for increased activity of coagulation system? - Answer Immobilized pt, heart
failure, estrogen levels (pregnancy, birth control pills, transgender)
Already Passed Answers Graded A+
2025-2026 Updated.
What may clot disorders be due to? - Answer -Issue with platelets or coagulation factors
-Hyper or hypo coagulability
How long do platelets live in circulation? - Answer 8-9 days
Where are many platelets stored? - Answer Spleen
When are platelets released? - Answer When needed
What is the function of platelets? - Answer To form platelet plug to increase clotting
What do the platelet granules release? - Answer Mediators
How many platelets are usually in the blood? - Answer 150,000-400,000/mL
Are platelets thrombocytes? - Answer Yes
Where are megakaryocytes formed and what do they do? - Answer Formed in the bone
marrow and break apart to form many platelets.
What does thrombopoietin control? - Answer Controls platelet production
Where is thrombopoietin made? - Answer In the liver, kidney, smooth muscle, and bone
marrow
What is the 1st stage of normal clotting and how long does it take to occur? - Answer -Vessel
spasm.
-Transient (< 1 min)
,What is the vessel spasm due to? - Answer Hormonal (thrombaxane A2) and neural control
What is the 2nd stage of clotting and how long does it take for it to occur? - Answer -
Formation of platelet plug
-Occurs within seconds
How does a platelet plug form? - Answer 1. Damaged vessel leaves collagen exposed
2. Von Willebrand factor is released by endothelial wall and attracts and activates platelets
3. Platelets "activated" and receptors bind to Von Willebrand factor and adhere to exposed
collagen
4. Chemical mediators released by platelets cause more platelet aggregation and clumping: ADP,
thromboxane A2 (a prostaglandin), thrombin causing nearby platelets to get sticky and clump
together
5. Activated platelets change shape and release chemical mediators causing more platelet
aggregation
6. Forms a loose platelet plug and activates the clotting cascade
What is the 3rd stage of clotting? - Answer Blood coagulation
What is blood coagulation? - Answer Process by which fibrinogen converted to fibrin, which
forms meshwork that holds blood cells together in clot which stabilizes clot
What happens during blood coagulation? - Answer -Coagulation factors become activated on
platelet surface and initiate clotting cascade:
^2 pathways (intrinsic and extrinsic) both end with activation of Factor X leading to conversion
of prothrombin to thrombin that converts fibrinogen to fibrin causing fibrin strands trap rbcs &
stabilizes clot
Where is the intrinsic pathway? - Answer Occurs in vascular system and is slow
Where is the extrinsic pathway? - Answer Occurs in tissues and is fast
Where do the intrinsic and extrinsic pathways converge? - Answer Factor 10
,What do procoagulation factors promote? - Answer Clotting
What procoagulation factor is needed in almost all steps of clotting? - Answer Calcium (factor
5)
What would the effect of hypocalcemia be on clotting? - Answer Hypocoagulation
What do anticoagulation factors do? - Answer Inhibit clotting
What are the natural anticoagulants? - Answer -Antithrombin III - neutralizes thrombin
-Protein C - inhibits thrombin
-Protein S - enhances action of Protein C
-Heparin - contained in granules in basophils
What happens when there are deficiency states of the natural anticoagulants? - Answer
Hypercoagulability
What is the 4th step of clotting? - Answer Clot retraction-contraction
What occurs during clot retraction-contraction? - Answer Platelets contract and squeeze
serum out of clot and pull vessel edges together causing shrinkage of clot
What is the 5th stage of clotting? - Answer Clot dissolution (fibrinolysis).
What does the clot start to do shortly after clot formation? - Answer Dissolve
What happens during fibrinolysis? - Answer Sequence of steps with activators and inhibitors
leading to formation of plasmin (enzyme) which lyses clots
Where does plasminogen circulate? - Answer In the blood
What activates plasminogen to plasmin and what happens because of it? - Answer Activated
to plasmin by tissue plasminogen activator (tPA) and urokinase-type plasminogen activator >
, What state are activators and inhibitors in a state of? - Answer Balance and both synthesized
by the liver and vascular endothelial lining
What does the breakdown of fibrin lead to? - Answer Production of fibrin degradation
products (can be measured in serum as indicator of fibrinolysis)
What are the hypercoagulable conditions due to? - Answer -Increased platelet function
-Increased activity of coagulation system
What would cause increased platelet function? - Answer Due to disturbance in blood flow,
endothelial damage or increased sensitivity of platelets to clotting factors
What diseases is increased platelet function seen? - Answer -Atherosclerosis
-Hypertension
-Cancers
-Thrombocytosis
What is thrombocytosis? - Answer 1 million platelets or more
What can cause increased activity of the coagulation system? - Answer -Hereditary conditions:
inherited defects in Factor V or prothrombin gene > increased incidence of recurrent DVTs/clots
-Stasis of blood flow: causes accumulation of platelets and activated clotting factors and is seen
with immobility, heart failure
-Activation of coagulation factors: high levels of estrogen, cancer, sepsis
What can result from increased activity of coagulation system? - Answer DVT, PE, MI, CVA,
PVD
Who is at risk for increased activity of coagulation system? - Answer Immobilized pt, heart
failure, estrogen levels (pregnancy, birth control pills, transgender)
