By Dr Musaddika Shaikh Dentowesome @drmusaddikashaikh

Defination :-

Arrest or prevention of bleeding by physiological process is called hemostasis

Factors :-

• F1. Fibrinogen 
• F2. Prothombin 
• F3. Thromboplastin 
• F4. Calcium 
• F5. Labile  
• F6. Not known 
• F7. Stable 
• F8. Antihaemophillic 
• F9. Christmas 
• F10. Stuart 
• F11. Plasma thrombin antecedent 
• F12. Hegman 
• F13. Fibrin stabilizing

Mechanism :-

Injury vessel walls – Formation of clot – Seal off damage blood vessel – Prevent blood loss

Series of event :-

Constriction of blood of blood vessel – Temporary haemostatic plug by platelet – haemostasis

Factors responsible for coagulation :-

• Fibrin formation :- by soluble plasma fibrinogen due to f3,f4,f6
• Thrombin formation :- inactive prothrombin into thrombin by prothrombin activator
• Prothrombin activator :- by extrinsic and intrinsic factor
• Clot retraction :- conversion of prothrombin to thrombin within 15-30min
• Role of Calcium :- it act as catalyst in cascade reaction

Why does not blood clot in circulation? Smoothness of endothelial line prevents adhesion. Negatively charged particles repells cloting factor. Natural anticoagulant eg :- heparin in circulation

Reference :- Book Human physiology for bds A.K Jain Google website slide player