What is role of vitamin K in blood clotting ?

Explanation

### Step-by-Step Solution:

1. **Understanding Blood Clotting**: Blood normally exists in a liquid state, but when there is an injury (like a cut), the body initiates a process to stop bleeding. This process involves transforming the liquid blood into a gel-like substance, which forms a clot and prevents excessive blood loss.

2. **The Clotting Process**: The blood clotting process begins with the conversion of prothrombin into thrombin. This conversion is facilitated by thromboplastin, which is formed in the presence of calcium ions.

3. **Role of Thrombin**: Thrombin then acts on fibrinogen, a soluble plasma protein, converting it into fibrin. Fibrin is insoluble and forms a mesh-like structure that traps blood cells, effectively creating a stable clot.

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