12 HEMOSTASIS AND BLOOD COAGULATION Flashcards
Hemostasis is defined as a process to:
a. Localize an injury
b. Restore normal anatomy
c. Stop bleeding from an injured blood vessel
d. Facilitate the removal of a clot
c. Stop bleeding from an injured blood vessel
Which of the following peripheral blood cells is involved in hemostasis?
a. Thrombocytes
b. Lymphocytes
c. Erythrocytes
d. Granulocytes
a. Thrombocytes
Primary hemostasis results in:
a. Formation of a thrombus
b. Retraction of the clot
c. Formulation of a platelet plug
d. Presence of vitamin K
c. Formulation of a platelet plug
For the control of bleeding, all the following characteristics are true except:
a. PF3 is important in activation of some coagulation factors.
b. Platelet adhesion is essential.
c. VIII:vWF acts as a glue for platelet-collagen binding to occur.
d. It is not necessary for platelets to aggregate with one another
d. It is not necessary for platelets to aggregate with one another
All the following factors will be inhibited by warfarin-type drugs except:
a. II
b. VII
c. VIII
d. X
c. VIII
Hemophilia A is a disorder associated with a deficiency of:
a. Factor VIII
b. Factor IX
c. Circulating platelets
d. Vitamin K–dependent coagulation factors
a. Factor VIII
Which factor is part of the common coagulation pathway?
a. VIII
b. X
c. XI
d. XII
b. X
Which factor is used only in the extrinsic coagulation pathway?
a. III
b. V
c. XII
d. VIII
a. III
Which factor is used only in the intrinsic coagulation pathway?
a. XII
b. V
c. VII
d. I
a. XII
Fibrinogen is synthesized in the:
a. Liver
b. Endothelium
c. Platelets
d. Plasma
a. Liver
Clot removal is accomplished by which of the following systems?
a. Fibrinolysis
b. Hemostasis
c. Anticoagulation
d. Thrombosis
a. Fibrinolysis
Protective mechanisms against thrombosis include all the following except:
a. Normal blood flow
b. Natural in vivo anticoagulants (such as AT III)
c. Cellular regulators that block the activation or action of plasmin
d. Antibodies produced by lymphocytes to block thrombin
d. Antibodies produced by lymphocytes to block thrombin
Which of the following is the anticoagulant of choice for routine coagulation assays?
a. Heparin
b. Sodium oxalate
c. Sodium citrate
d. Lithium oxalate
c. Sodium citrate
The prothrombin assay requires that the patient’s citrated plasma be combined with which of the following?
a. Thromboplastin
b. Calcium chloride and thromboplastin
c. Calcium chloride
d. Kaolin
b. Calcium chloride and thromboplastin
What does the silicate (kaolin) do in the test system for APTT?
a. It binds calcium so that clotting does not occur.
b. It activates tissue thromboplastin.
c. It facilitates platelet adherence to endothelial surfaces.
d. It allows more complete activation of coagulation factor XII, thus shortening the clotting times.
b. It activates tissue thromboplastin.
