What are the functions of Vitamin K in human body?

The term ‘vitamin K’ is a generic term used for all compounds possessing cofactor activity for γ-glutamylcarboxylase.

Two forms of vitamin K exist in nature: vitamin K1 and vitamin K2. Vitamin K1 or phylloquinone, is found in plant foods. Vitamin K2, or menaquinone, is synthesized by intestinal bacteria.

Vitamin K is fat soluble. Vitamin K plays a crucial role in hemostasis. It is necessary for the synthesis of prothrombin (factors II) and several other hepatic clotting factors.

All these factors and proteins plus calcium are key links in the chain of events producing a blood clot. 

Although the role of vitamin K in the coagulation process is the most well known, vitamin K has additional metabolic functions including bone mineralization, vascular calcification and cell growth.

Vitamin K also was found participates with vitamin D in synthesizing the bone protein, which helps to regulate serum calcium levels.

Leafy vegetables, cabbage, spinach, cauliflower, broccoli, fruit and liver are especially good sources of vitamin K, although moderate amounts are found in many other vegetables, as well, as in cereals.

A deficiency of vitamin K causes hypoprothrombinemia and a tendency to bleed excessively. Newborn hemorrhagic disease is the classic example of vitamin K deficiency.

It is believed that humans ordinarily receive adequate amounts of vitamin K in the diet.
What are the functions of Vitamin K in human body?