Final answer:
Hemostasis involves three mechanisms: vascular spasm, platelet plug formation, and coagulation. Intrinsic and extrinsic pathways contribute to coagulation. Key reagents used in tests include thromboplastin and calcium ions. The hemostasis functions measured include platelet activation, adhesion, aggregation, and clot formation.
Step-by-step explanation:
There are three mechanisms involved in hemostasis: vascular spasm, formation of a platelet plug, and coagulation. Vascular spasm is the constriction of the blood vessel to reduce blood flow. The formation of a platelet plug involves platelets adhering to the damaged area of the blood vessel and sticking together to form a clot.
Coagulation is the final step where a fibrin clot is formed to repair the vessel wall. Intrinsic and extrinsic pathways both contribute to coagulation, leading to the common pathway.
The intrinsic pathway is initiated by the exposure of collagen in the blood vessel wall, while the extrinsic pathway is initiated by tissue factor released from damaged tissues.
Key reagents used in these tests include thromboplastin, calcium ions, and clotting factor assays. These tests measure the hemostasis functions of platelet activation, platelet adhesion, platelet aggregation, and clot formation.