Question

Place the steps of hemostasis listed below in the correct order. Note: This is a six (6) point question.

1. Conversion of fibrinogen into fibrin
2. Conversion of prothrombin into thrombin
3. Adhesion and aggregation of platelets to collagen fibers of damaged vessel
4. Prothrombin activator formed by extrinsic or intrinsic pathway
5. Reduction of blood loss by initiation of a vascular spasm 6. Activation of Factor X
A) 3,5,6,4,2,1
B) 5,3,6,4,2,1
C) 5,3,6,2,4,1
D) 3,5,4,6,2,1

Answer 1

The correct order of steps for hemostasis after a blood vessel injury is to initiate a vascular spasm, followed by platelet adhesion and aggregation, Factor X activation, prothrombin activator formation, conversion of prothrombin to thrombin, and conversion of fibrinogen to fibrin, which makes Option B) 5,3,6,4,2,1 the correct answer.

Step-by-step explanation:

The proper sequence for the steps of hemostasis begins with the vascular spasm to reduce blood loss immediately following an injury. Following the vascular spasm, platelets adhere to the site of the damaged vessel and aggregate to form a temporary plug. Activation of Factor X occurs next, which is then followed by the formation of prothrombin activator through either the intrinsic or extrinsic pathways leading to the common pathway. Subsequently, prothrombin is converted into thrombin, and finally, thrombin catalyzes the conversion of fibrinogen into fibrin, which strengthens the clot. The correct order for these steps is therefore:

1. Reduction of blood loss by initiation of a vascular spasm
2. Adhesion and aggregation of platelets to collagen fibers of damaged vessel
3. Activation of Factor X
4. Prothrombin activator formed by extrinsic or intrinsic pathway
5. Conversion of prothrombin into thrombin
6. Conversion of fibrinogen into fibrin

So the correct answer to the question is:

Option B) 5,3,6,4,2,1